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General HIFI => Transports => Topic started by: stevenvalve on May 22, 2014, 02:56:24 PM

Title: Computer transport interface
Post by: stevenvalve on May 22, 2014, 02:56:24 PM
 I have 6 terabytes of computer stored music via wave files and I need to play them without turning them back to CDs, So I need a computer transport but unfortunately they still do not quite cut it. I have word from our tech heads that this is the interface to get, its cheap and could be the best around. It has direct Clock, word, Data, Ground. including galvanic isolation. Danny Digital has one on order for evaluation.  What do you guy's think, do we buy one. http://www.ebay.com.au/itm/XMOS-DSD-384-kHz-32bit-multi-format-USB-to-I2S-SPDIF-/251531449671?pt=LH_DefaultDomain_0&hash=item3a90715547
Title: Re: Computer transport interface
Post by: stevenvalve on May 22, 2014, 02:59:17 PM
This model has an inbuilt DAC. Looks good, what do you think.  http://www.ebay.com.au/itm/XMOS-DSD-384-kHz-32bit-USB-to-I2S-SPDIF-PCB-DAC-PCM5102-/251531452390?pt=LH_DefaultDomain_0&hash=item3a90715fe6
Title: Re: Computer transport interface
Post by: Tuyen on May 22, 2014, 03:38:37 PM
It looks interesting.  Feature rich.

I use an XMOS based USB to I2S interface too powered by dedicated 5V power supply.
http://luckit.biz/ (http://luckit.biz/)

Very happy with it.   

Thing is though, I can't imagine computer audio ever reaching sonic expectations for any KDAC users.  So many (sometimes unavoidable) SMD components in the path.  Potentially be a big waste of valuable time/money.   No??
Title: Re: Computer transport interface
Post by: ozmillsy on May 22, 2014, 04:33:07 PM
How does the clocking work?
Title: Re: Computer transport interface
Post by: treblid on May 22, 2014, 05:30:44 PM
What's XMOS?

Title: Re: Computer transport interface
Post by: dannydigital on May 22, 2014, 05:33:07 PM
I have 6 terabytes of computer stored music via wave files and I need to play them without turning them back to CDs, So I need a computer transport but unfortunately they still do not quite cut it. I have word from our tech heads that this is the interface to get, its cheap and could be the best around. It has direct Clock, word, Data, Ground. including galvanic isolation. Danny Digital has one on order for evaluation.  What do you guy's think, do we buy one. http://www.ebay.com.au/itm/XMOS-DSD-384-kHz-32bit-multi-format-USB-to-I2S-SPDIF-/251531449671?pt=LH_DefaultDomain_0&hash=item3a90715547

When I get it, I will initially be trying it out for DSD audio. I will integrate it in with my Pioneer DV-989AVi which I modified for 2 channels only. I'll use the DAC in it to stream DSD. It has quite a reasonable BB DAC (PCM1738E) with an analogue stage that's been modified with OPA627's and 2SK170/2SJ74 complementary FET output.
Should be quite interesting.

I imagine the USBtoI2S board will have plenty of potential for upgrade tinkering, especially in the clock re-generators.

Hope to get it soon.  :D

p.s. The board is available from this site too: http://jlsounds.com/products.html


Title: Re: Computer transport interface
Post by: zenelectro on May 23, 2014, 01:06:17 AM
When I get it, I will initially be trying it out for DSD audio. I will integrate it in with my Pioneer DV-989AVi which I modified for 2 channels only. I'll use the DAC in it to stream DSD. It has quite a reasonable BB DAC (PCM1738E) with an analogue stage that's been modified with OPA627's and 2SK170/2SJ74 complementary FET output.
Should be quite interesting.

I imagine the USBtoI2S board will have plenty of potential for upgrade tinkering, especially in the clock re-generators.

Hope to get it soon.  :D

p.s. The board is available from this site too: http://jlsounds.com/products.html

Danny,

I'm not sure what you mean by 'regeneration' -  it is just a synchronous re-clocking arrangement.

The big issue with these boards is they require galvanic isolation, but the isolators add jitter.
As such the clock needs to be DAC side of the isolator and a/ be sent back through the isolator
b/ re clock signals coming out of the isolator.

Also not sure which isolators they are using as there are quite a few different technologies
ATM all with various trade offs. Theoretically if the reclocking is done correctly this shouldn't
matter. We will see.

They appear to have done this correctly (I think). Then it's a case of types of clocks, logic
used for reclocking, bypassing, layout etc etc.

The price is pretty amazing for what they do - so I'm getting one.

cheers,

Terry
Title: Re: Computer transport interface
Post by: zenelectro on May 23, 2014, 01:07:51 AM
It looks interesting.  Feature rich.

I use an XMOS based USB to I2S interface too powered by dedicated 5V power supply.
http://luckit.biz/ (http://luckit.biz/)

Very happy with it.   

Thing is though, I can't imagine computer audio ever reaching sonic expectations for any KDAC users.  So many (sometimes unavoidable) SMD components in the path.  Potentially be a big waste of valuable time/money.   No??

The Luckit is OK, has Galv isolation but no re clocking after the isolators.

T
Title: Re: Computer transport interface
Post by: zenelectro on May 23, 2014, 01:09:57 AM
It looks interesting.  Feature rich.

I use an XMOS based USB to I2S interface too powered by dedicated 5V power supply.
http://luckit.biz/ (http://luckit.biz/)

Very happy with it.   

Thing is though, I can't imagine computer audio ever reaching sonic expectations for any KDAC users.  So many (sometimes unavoidable) SMD components in the path.  Potentially be a big waste of valuable time/money.   No??

PC audio will surpass the KillerDAC - no question.  It's just a question of who can do it.

My money is on DSD replay being the best solution. 

T
Title: Re: Computer transport interface
Post by: zenelectro on May 23, 2014, 01:11:35 AM
How does the clocking work?

USB -> I2S asynchronous operation means the clocks are fixed (not pullable) on DAC side and the computer
just feeds data to a small buffer on demand. This is the best way.
Title: Re: Computer transport interface
Post by: ozmillsy on May 23, 2014, 08:44:31 AM
USB -> I2S asynchronous operation means the clocks are fixed (not pullable) on DAC side and the computer
just feeds data to a small buffer on demand. This is the best way.
It's probably my lack of knowledge.   But what I was thinking,,,,,   how does the Killerdac derive an 11M clocking signal from this board?     Doed it just sync to 22M?
Title: Re: Computer transport interface
Post by: Greg Erskine on May 23, 2014, 09:18:17 AM
Hi,

Have you guys been following this thread closely?

http://killerdac.com/forum/index.php/topic,842.msg19303.html#msg19303

IMO they have got it right, a small Linux computer in the DAC, i2s out directly to the DAC chip(s). Add an i2s isolator if you must.

I can't see the point of adding the costs of a PC and USB hardware, also no S/PDIF, no audiophile USB cables.

I'd love to see you guys develop a KillerRasPi.

regards
Title: Re: Computer transport interface
Post by: zenelectro on May 23, 2014, 12:14:57 PM
It's probably my lack of knowledge.   But what I was thinking,,,,,   how does the Killerdac derive an 11M clocking signal from this board?     Doed it just sync to 22M?

Andrew,

The I2S will OP 2.8MHz clock - I think. Haven't looked at data sheet. Do they have one??

I did some research on these USB converters and will probably steer away from them. There are compromises.
 
T



 
Title: Re: Computer transport interface
Post by: zenelectro on May 23, 2014, 12:18:44 PM
Hi,

Have you guys been following this thread closely?

http://killerdac.com/forum/index.php/topic,842.msg19303.html#msg19303

IMO they have got it right, a small Linux computer in the DAC, i2s out directly to the DAC chip(s). Add an i2s isolator if you must.

I can't see the point of adding the costs of a PC and USB hardware, also no S/PDIF, no audiophile USB cables.

I'd love to see you guys develop a KillerRasPi.

regards

Greg,

It's not that simple, as stated before, if you add the isolator you need to add reclocking to
remove (attenuate) jitter that isolator adds.

Terry
Title: Re: Computer transport interface
Post by: Tuyen on May 23, 2014, 01:29:15 PM
As an avid computer audio user, very keen to follow how Terry and Danny get along with the usb boards and what you guys find are worthwhile modifications/power supply/clocking/computer setups.

Hope you guys get a good result and have a chance to share your experiments and results on the forum.  ;D
Title: Re: Computer transport interface
Post by: ozmillsy on May 23, 2014, 01:46:30 PM
The I2S will OP 2.8MHz clock - I think. Haven't looked at data sheet. Do they have one??

It outputs DSD over PCM.

Quote
5)   DSD Audio over PCM frames. DSD64(2.822400MHz) and DSD128(5.644800MHz) by method DoP with 0x05/0xFA markers.

Steven opened the thread by suggesting this USB interface ticks a lot of boxes (as a potential solution for the Killerdac?).
Which it potentially is, given it is a multi format interface.

My concern is the output clock timings may not be suitable for the TDA1541A ? (not sure)   Here they are......

(https://dl.dropboxusercontent.com/u/1370915/Audio/xmos_mclk_outputs.JPG)

The specs were on the ebay listing,,,,,
http://www.ebay.com.au/itm/XMOS-DSD-384-kHz-32bit-multi-format-USB-to-I2S-SPDIF-/251531449671?pt=LH_DefaultDomain_0&hash=item3a90715547 (http://www.ebay.com.au/itm/XMOS-DSD-384-kHz-32bit-multi-format-USB-to-I2S-SPDIF-/251531449671?pt=LH_DefaultDomain_0&hash=item3a90715547)
Title: Re: Computer transport interface
Post by: Greg Erskine on May 23, 2014, 02:19:41 PM
Greg,

It's not that simple, as stated before, if you add the isolator you need to add reclocking to
remove (attenuate) jitter that isolator adds.

Terry

Hi Terry,

I am not sure I follow 100%. The picture I linked to has a Raspberry Pi connected to the DDDAC directly via i2s, no isolation.

I thought I had seen pictures of a isolation board using i2s but can't find the picture (it may have been just a USB to is2 board?).

Are you referring specifically to the KillerDAC and using an isolation board?

My lack of knowledge tends to make me view things in a simplistic manner. :o

regards



Title: Re: Computer transport interface
Post by: omodo on May 23, 2014, 02:25:45 PM

It outputs DSD over PCM.

Steven opened the thread by suggesting this USB interface ticks a lot of boxes (as a potential solution for the Killerdac?).
Which it potentially is, given it is a multi format interface.

My concern is the output clock timings may not be suitable for the TDA1541A ? (not sure)   Here they are......

(https://dl.dropboxusercontent.com/u/1370915/Audio/xmos_mclk_outputs.JPG)

The specs were on the ebay listing,,,,,
http://www.ebay.com.au/itm/XMOS-DSD-384-kHz-32bit-multi-format-USB-to-I2S-SPDIF-/251531449671?pt=LH_DefaultDomain_0&hash=item3a90715547 (http://www.ebay.com.au/itm/XMOS-DSD-384-kHz-32bit-multi-format-USB-to-I2S-SPDIF-/251531449671?pt=LH_DefaultDomain_0&hash=item3a90715547)

the top row on that chart is suitable for 1541a, i.e. 44.1kHz Fs, BCK 64* Fs = 2.8Mhz

and should play up to 96khz fine, i think bck is limited to 6.4mhz on 1541a
Title: Re: Computer transport interface
Post by: ozmillsy on May 23, 2014, 03:04:16 PM
the top row on that chart is suitable for 1541a, i.e. 44.1kHz Fs, BCK 64* Fs = 2.8Mhz
Ok, cool.     For some reason I thought there was a restriction to an 11M master clock speed,  but you're saying it's less than 11M so it's fine.   
Title: Re: Computer transport interface
Post by: kajak12 on May 23, 2014, 05:59:50 PM
PC audio will surpass the KillerDAC - no question.  It's just a question of who can do it.

My money is on DSD replay being the best solution. 

T
Now your talking but yet to hear it......................
Title: Re: Computer transport interface
Post by: Tuyen on May 23, 2014, 06:50:21 PM
Slightly off-topic, but has any KDAC users tried hooking up the KDAC's finely tuned output stage on a different DAC board (i.e. a chip that supports hi-res/dsd input)?     If so,  is the 'magic' still there?      Or is the TDA1541 chip the crucial heart of the KDAC's signature sound?   

Is the idea of trying these new hi-res USB-I2s converters, to convert hi-res/DSD files down to 16/44 so the TDA1541 based KDACs can play?  downsampling via software/hardware?      Or is the intention to work on a hi-res supported DAC chip with the KDAC's tube output stage bolted on?
Title: Re: Computer transport interface
Post by: Rob181 on May 23, 2014, 07:42:03 PM
PC audio will surpass the KillerDAC - no question.  It's just a question of who can do it.

My money is on DSD replay being the best solution. 

T

That being the case...is it possible to "graft" a KD output stage to something like PS Audio Direct Stream DSD Dac....
Title: Re: Computer transport interface
Post by: zenelectro on May 23, 2014, 07:54:35 PM
Hi Terry,

I am not sure I follow 100%. The picture I linked to has a Raspberry Pi connected to the DDDAC directly via i2s, no isolation.

I thought I had seen pictures of a isolation board using i2s but can't find the picture (it may have been just a USB to is2 board?).

Are you referring specifically to the KillerDAC and using an isolation board?

My lack of knowledge tends to make me view things in a simplistic manner. :o

regards

The link you posted is using WaveIO USB->I2S board. Ref picture below. It has both GMR isolated and direct I2S
outputs. The isolated OP is not re-clocked.

cheers

T

Title: Re: Computer transport interface
Post by: zenelectro on May 23, 2014, 07:58:52 PM
That being the case...is it possible to "graft" a KD output stage to something like PS Audio Direct Stream DSD Dac....

Of course, but a PS audio direct stream DAC is a very expensive piece of kit that can be improved upon WRT performance.

You would also have to throw away most of the OP level to make it suitable for the KD triode OP stage.

There are better options than the PS audio DAC and for cheaper for DSD OP.

Stay tuned. :)

 T

Title: Re: Computer transport interface
Post by: zenelectro on May 23, 2014, 08:01:21 PM
Now your talking but yet to hear it......................

Hey Mario,

Ultimately it will be subjective - but if you want to get closer to the sound of analog master tape, I
think DSDx128 will do it.

T


 
Title: Re: Computer transport interface
Post by: zenelectro on May 23, 2014, 08:03:36 PM
Ok, cool.     For some reason I thought there was a restriction to an 11M master clock speed,  but you're saying it's less than 11M so it's fine.

Oz,

You are confusing master clock (mck) with bit clock. Bit clock of I2S runs at 2.8MHz.

cheers

Terry
Title: Re: Computer transport interface
Post by: zenelectro on May 23, 2014, 08:09:01 PM
Slightly off-topic, but has any KDAC users tried hooking up the KDAC's finely tuned output stage on a different DAC board (i.e. a chip that supports hi-res/dsd input)?     If so,  is the 'magic' still there?      Or is the TDA1541 chip the crucial heart of the KDAC's signature sound?   

Is the idea of trying these new hi-res USB-I2s converters, to convert hi-res/DSD files down to 16/44 so the TDA1541 based KDACs can play?  downsampling via software/hardware?      Or is the intention to work on a hi-res supported DAC chip with the KDAC's tube output stage bolted on?

I think ultimately they are different beasts. The KD dual triode OP stage has a gain of around 30 so the IP level is pretty low for a few volts OP.

A DSD converter will have more OP level so there are more possibilities WRT analog stages. Also DSD is an inherently different beast
sound wise and will most likely require some OP stage tweaking to suit it's characteristics. There's also the RF noise to consider.

I would say leave the KD for what it does and start fresh - just gut feeling.

T
Title: Re: Computer transport interface
Post by: Tuyen on May 23, 2014, 08:33:27 PM
Hey Terry,

Would one of these usb to i2s modules provide better performance 'out of the box' over the waveio im using ?   Or does it just have 'potential' to be better if I add external clocking or something along those lines?


Whats your chip of choice for highres/dsd?  Sabre es9018?

Hrmm.. got me thinking..  KillerDDDAC!   Hehehe
Title: Re: Computer transport interface
Post by: kajak12 on May 23, 2014, 08:46:42 PM
Hey Mario,

Ultimately it will be subjective - but if you want to get closer to the sound of analog master tape, I
think DSDx128 will do it.

T
I think dsd is far from it unless you can come up with something we are phukedddd
Title: Re: Computer transport interface
Post by: ozmillsy on May 23, 2014, 08:53:22 PM
I think dsd is far from it unless you can come up with something we are phukedddd
He will.   All good things take time.   :)

Having to 'live' with 16bit for the time being is such sweeet sorrow.     ;D
Title: Re: Computer transport interface
Post by: Tuyen on May 23, 2014, 10:01:16 PM
The whole idea of 'computer audio' will only work if you yourself actually want it to.

If you are a person who doesn't like the idea of using computers in general or the idea of storing/accessing your music library from say an ipad,   I reckon even if the resultant sound is as good as the 'analog tape',   it still wouldnt be 'good enough'.

Another example is like vinyl rips.  When I had my turntable setup running, I thought it sounded great.   I played a copy of the 24/96 vinyl rip I downloaded and played it through my digital system and felt it sounded just as good. Possibly even better.  Yet there are vinyl advocates out there that still believe the sound of vinyl is (and will always be) more 'real' than any digital source.    What we audiophiles 'think' sounds more 'real' is more than just what comes out of the speakers. 

That's my observations from most of the people I've met in this hobby so far.

Title: Re: Computer transport interface
Post by: dannydigital on May 23, 2014, 10:08:43 PM
Ok, cool.     For some reason I thought there was a restriction to an 11M master clock speed,  but you're saying it's less than 11M so it's fine.


The TDA1541 is not timed by the master clock (no master clock pin), just L/R select timing (Word), Bit Clock (Clock) and the Audio Data (Data) which together = I2S.

The Master Clock (11.2896MHz) in the Philips CD system is required to clock the decoder chip (A) and the oversampling /interpolation chip (B) which most people prefer to bypass (i.e. no oversampling). The decoder chip (A) then produces the above I2S signaling.
Title: Re: Computer transport interface
Post by: Greg Erskine on May 23, 2014, 10:47:08 PM
The link you posted is using WaveIO USB->I2S board. Ref picture below. It has both GMR isolated and direct I2S
outputs. The isolated OP is not re-clocked.

cheers

T

Hi Terry,

Oh I see the confusion now. Although there is a WaveIO USB-I2S board in the picture it is not connected to the DDDAC. The computer it is plugged into is not powered up either.

The Raspberry Pi, which is underneath the WaveIO board has its I2S (P5) connected directly to the DAC.

regards
Title: Re: Computer transport interface
Post by: dannydigital on May 23, 2014, 10:51:52 PM
Danny,

I'm not sure what you mean by 'regeneration' -  it is just a synchronous re-clocking arrangement.

The big issue with these boards is they require galvanic isolation, but the isolators add jitter.
As such the clock needs to be DAC side of the isolator and a/ be sent back through the isolator
b/ re clock signals coming out of the isolator.

Also not sure which isolators they are using as there are quite a few different technologies
ATM all with various trade offs. Theoretically if the reclocking is done correctly this shouldn't
matter. We will see.

They appear to have done this correctly (I think). Then it's a case of types of clocks, logic
used for reclocking, bypassing, layout etc etc.

The price is pretty amazing for what they do - so I'm getting one.

cheers,

Terry

Terry,

The device seems to be re-clocking on the DAC side, not sure if it feeds the timing back over the isolation though.
I can see that it uses an LC574A (D flop-flops) that looks like it's clocked with the oscillators on the isolated side to output the signals.
Two oscillators I can see there (isolated side), I think one for PCM stuff and the other for DSD maybe.

http://www.datasheetdir.com/LC574A+download

It will be interesting to play with the L & R DSD streams, supposedly DSD is just decoded by some LPF setup. Maybe this can be somehow discretely implemented.

D
Title: Re: Computer transport interface
Post by: ozmillsy on May 23, 2014, 11:30:31 PM
The Master Clock (11.2896MHz) in the Philips CD system is required to clock the decoder chip (A) and the oversampling /interpolation chip (B) which most people prefer to bypass (i.e. no oversampling). The decoder chip (A) then produces the above I2S signaling.
That clears it up, thanks Danny.
Title: Re: Computer transport interface
Post by: zenelectro on May 24, 2014, 07:35:04 AM
Terry,

The device seems to be re-clocking on the DAC side, not sure if it feeds the timing back over the isolation though.


Danny,

As you are probably aware, sending  the clock back through isolators is required for the reclocking to
work properly and everything to be synchronous. That's one thing I always look for. Also the clock
selection (44.1 / 48 multiples) hi/lo sig needs to be sent through isolators. It's all pretty complex to
do correctly.

Quote


I can see that it uses an LC574A (D flop-flops) that looks like it's clocked with the oscillators on the isolated side to output the signals.
Two oscillators I can see there (isolated side), I think one for PCM stuff and the other for DSD maybe.

http://www.datasheetdir.com/LC574A+download


One oscillator for 44.1 / 88.2 / 176.4 (and DSD) etc one for 48 / 96 / 192 etc.

Quote

It will be interesting to play with the L & R DSD streams, supposedly DSD is just decoded by some LPF setup. Maybe this can be somehow discretely implemented.


I had a look at this board and some of the feedback from users at DIYA. It seems that even though he claims
to have implemented re clocking, it is still very susceptible to cables, source etc etc. I'm guessing the
implementation is just not up to scratch.

I think best way is to implement the whole reclocking isolation scenario as a separate board. More work.

For the money it's worth having a play with though.

T


Title: Re: Computer transport interface
Post by: zenelectro on May 24, 2014, 07:49:39 AM
Terry,

The device seems to be re-clocking on the DAC side, not sure if it feeds the timing back over the isolation though.

Looking at close up they have used Si Labs 8661BC isolator. This has 5 x 'forward' channels and 1 x 'reverse' channel.
That reverse one will be for the clock going back.

T
Title: Re: Computer transport interface
Post by: omodo on May 24, 2014, 09:27:14 AM

I had a look at this board and some of the feedback from users at DIYA. It seems that even though he claims
to have implemented re clocking, it is still very susceptible to cables, source etc etc. I'm guessing the
implementation is just not up to scratch.


IME even with Ian's FIFO (+isolator + si570 reclocker) changes to source (usb-i2s module - amenero vs waveio), software & even usb cable ($5 special vs furutech) was audible... and it's meant to be the DIY reference implementation?..
Title: Re: Computer transport interface
Post by: zenelectro on May 24, 2014, 10:18:36 AM
IME even with Ian's FIFO (+isolator + si570 reclocker) changes to source (usb-i2s module - amenero vs waveio), software & even usb cable ($5 special vs furutech) was audible... and it's meant to be the DIY reference implementation?..

Yep I hear you.

Look - to do one of these boards -really- well would most likely require a 4 layer board
and a -lot- of experience / time to get everything obsessively right.

It's all pretty high speed with a lot going on and everything (noise) gets everywhere
very easily.

Would it be worth he time  - buggered if I know?  :) 


T
Title: Re: Computer transport interface
Post by: dannydigital on May 24, 2014, 02:46:35 PM
O.k. I've got it,

We can put a black hole next to the isolator, suck all the noise out....and theen re-clock it!

Just gotta find the right black hole, vgot some datasheets here somwhere.  :P

D
Title: Re: Computer transport interface
Post by: kajak12 on May 24, 2014, 03:46:54 PM
The whole idea of 'computer audio' will only work if you yourself actually want it to.

If you are a person who doesn't like the idea of using computers in general or the idea of storing/accessing your music library from say an ipad,   I reckon even if the resultant sound is as good as the 'analog tape',   it still wouldnt be 'good enough'.

Another example is like vinyl rips.  When I had my turntable setup running, I thought it sounded great.   I played a copy of the 24/96 vinyl rip I downloaded and played it through my digital system and felt it sounded just as good. Possibly even better.  Yet there are vinyl advocates out there that still believe the sound of vinyl is (and will always be) more 'real' than any digital source.    What we audiophiles 'think' sounds more 'real' is more than just what comes out of the speakers. 

That's my observations from most of the people I've met in this hobby so far.
Tuyen what have you been smoking lately i would like some.............
Title: Re: Computer transport interface
Post by: zenelectro on May 24, 2014, 06:36:24 PM
O.k. I've got it,

We can put a black hole next to the isolator, suck all the noise out....and theen re-clock it!

Just gotta find the right black hole, vgot some datasheets here somwhere.  :P

D

That's it Danny. :)

I just bought one myself. Should be a good project.
Getting re familiarized with Design Spark.   

T
Title: Re: Computer transport interface
Post by: Rob181 on May 24, 2014, 06:39:59 PM
Of course, but a PS audio direct stream DAC is a very expensive piece of kit that can be improved upon WRT performance.

You would also have to throw away most of the OP level to make it suitable for the KD triode OP stage.

There are better options than the PS audio DAC and for cheaper for DSD OP.

Stay tuned. :)

 T

You bet your life I will stay tuned...really looking forward to what "rabbit you can pull out of a hat" with this...like MANY others I am moving to computer audio & would really appreciate a Killer DSD...especially once that has 2 inputs...1 x USB for the computer & 1 x I2S for the CD Transport...Rob
Title: Re: Computer transport interface
Post by: Tuyen on May 25, 2014, 11:51:00 AM
Do you guys believe the issue of 'noise' being one of the primary things to focus on trying to get 'right', with these usb-i2s converters?    I.e.  does the discussion about these clocking/reclocking function directly affect the output 'noise'?

If so, would it be worth measuring the unique 'noise' profiles of a fully tweaked Marantz CD94/Wadia unit that are currently considered ultimate i2s transports and try to replicate this noise profile on these USB modules?  Or is the aim really just to get 'lowest' noise possible?   

Sorry if I'm over simplifying things!    Just very interested in the whole topic of usb-i2s interfaces vs  disc-i2s interfaces.  Not knowledgeable or technical enough. Have only ever executed primitive and totally subjective listening tests and comparisons in the past.
Title: Re: Computer transport interface
Post by: ozmillsy on May 25, 2014, 12:11:25 PM
Jitter is a bit of a phenomena, IMHO.

Take the Zenclock.   It was designed in a way to ensure lowest possible jitter distortion.   We put it into my cd94, and it was kind of cold/clinical.   Terry then tweaked it, and the result was all this harmonic beauty going on.  I believe the tweak resulted in higher jitter distortion.

It's almost like some static jitter is needed for a more pleasing sound,  but I dont know why that is, it's almost counter intuitive.
Title: Re: Computer transport interface
Post by: kajak12 on May 25, 2014, 12:19:22 PM
Jitter is a bit of a phenomena, IMHO.

Take the Zenclock.   It was designed in a way to ensure lowest possible jitter distortion.   We put it into my cd94, and it was kind of cold/clinical.   Terry then tweaked it, and then result was all this harmonic beauty going on.  I believe the tweak resulted in higher jitter distortion.

It's almost like some static jitter is needed for a more pleasing sound,  but I dont know why that is, it's almost counter intuitive.

Do you guys believe the issue of 'noise' being one of the primary things to focus on trying to get 'right', with these usb-i2s converters?    I.e.  does the discussion about these clocking/reclocking function directly affect the output 'noise'?

If so, would it be worth measuring the unique 'noise' profiles of a fully tweaked Marantz CD94/Wadia unit that are currently considered ultimate i2s transports and try to replicate this noise profile on these USB modules?  Or is the aim really just to get 'lowest' noise possible?   

Sorry if I'm over simplifying things!    Just very interested in the whole topic of usb-i2s interfaces vs  disc-i2s interfaces.  Not knowledgeable or technical enough. Have only ever executed primitive and totally subjective listening tests and comparisons in the past.

Jitter is a unknown dark secret while developing the zen clock its amazing how a few changes in the clock affect the sound what we need is accurate measurements just to plot the jitter aspects and what sound real
Title: Re: Computer transport interface
Post by: zenelectro on May 25, 2014, 01:19:55 PM
Jitter is a bit of a phenomena, IMHO.

Take the Zenclock.   It was designed in a way to ensure lowest possible jitter distortion.   We put it into my cd94, and it was kind of cold/clinical.   Terry then tweaked it, and the result was all this harmonic beauty going on.  I believe the tweak resulted in higher jitter distortion.

It's almost like some static jitter is needed for a more pleasing sound,  but I dont know why that is, it's almost counter intuitive.

Oz,

WRT adding jitter, I don't that is the case. I tweaked the oscillator load, making it lighter, ie; unloading it. On Nathans I unloaded it even further.

I don't think this would add jitter and could very well lower it. I wish I had the test gear to measure it.

One thing is for sure, unloading the oscillator increased the sine wave voltage OP, (before squaring) so that well may have lowered jitter.


cheers

T
Title: Re: Computer transport interface
Post by: ozmillsy on May 25, 2014, 02:08:32 PM
I don't think this would add jitter and could very well lower it. I wish I had the test gear to measure it.

One thing is for sure, unloading the oscillator increased the sine wave voltage OP, (before squaring) so that well may have lowered jitter.
Doesnt loading the oscillator ensure a tighter square wave?

What is the theory in loading it?
Title: Re: Computer transport interface
Post by: gamve on May 25, 2014, 03:23:47 PM
Watching this topic with some interest.
A question for all you guys. Has anyone heard a decent (and by decent I mean nearly as good as a
dedicated transport/DAC or well sorted analogue system) reasonably priced PC based audio system.
Has anyone heard a decent PC based music system at any price?

If you have had experience with either system, has this system been used successfully for a reasonable
period of time without constant pissing around with both the software and the hardware, ie complete and
going reliably without any modifications for six months or more?

Is it a mandatory and expected fact that if you use a PC for digital audio you are committing to using most
of your listening time fcuking about with useless sh!t equipment and crap technology designed for a totally
different purpose. If I want a piece of toast I put it in the toaster not the bloody washing machine.  :D

Do you really believe a $99.00 kit board solution will be the answer to all your digital dreams? or are you
all deluded?  :-*

Title: Re: Computer transport interface
Post by: ozmillsy on May 25, 2014, 04:02:49 PM
LOL

I have had good results with a MacMini running Audirvana.

I use it for playing native DSD files into a DSD dac (cheap unit).   

I dont use it on my main system.   Just doesnt compare, but that is more to do with the dac than the macmini (I reckon).

One day I'll have a SOTA KillerDSD.  :)
Title: Re: Computer transport interface
Post by: Tuyen on May 25, 2014, 04:34:22 PM
I was using a little netbook running foobar2000 playback software into a USB DDDAC1543 MK2. Perfectly content with the sound quality I was getting from the setup for the 3 years I had it.   Have lost all  interest in any disc spinners as a primary digital transport since. hehe

Only decided to try the newer high-res supported USB DDDAC1794 last year and have been enjoying it too.  Don't mind trying small software/hardware tweaks that get posted around the place, as long as they aren't too costly and don't involve too much effort.
Title: Re: Computer transport interface
Post by: Tuyen on May 25, 2014, 04:47:55 PM
I'd be interested in reading about forum member's personal experiences of which computer transport interfaces(hardware and software) they have tried on their own dac/system and how they found it compared to their cd transport.   Do understand it is completely subjective, but still interesting to me none-the-less :)
Title: Re: Computer transport interface
Post by: Tuyen on May 25, 2014, 04:56:20 PM
PC audio will surpass the KillerDAC - no question.  It's just a question of who can do it.

My money is on DSD replay being the best solution. 

T

Hi Terry,

What's your reason for saying DSD being the best solution?

The whole PCM vs DSD and which format is superior, doesn't seem to be black and white from what I can gather reading various forums.

Official DSD releases are so so limited too.  I can't see it growing that fast anytime soon.   Do you feel there really is any point putting much effort into getting a solution that is done 'right' ?    Or is the idea of DSD more for recording and replaying of vinyl/tape rips?

Has any forums members compared a 24/96 vinyl rip (or tape rip) on their digital system (even if converted to 16/44 and burnt to CD for playback)  to the actual record on their turntable?     If so,   how do they compare sonically?  What aspects in the sound do you feel you lose  from the conversion/playback process?
Title: Re: Computer transport interface
Post by: ozmillsy on May 25, 2014, 05:08:43 PM
Has any forums members compared a 24/96 vinyl rip (or tape rip) on their digital system (even if converted to 16/44 and burnt to CD for playback)  to the actual record on their turntable?     If so,   how do they compare sonically?  What aspects in the sound do you feel you lose  from the conversion/playback process?
I just did that yesterday, and posted about it in the Vinyl section.
Title: Re: Computer transport interface
Post by: stevenvalve on May 25, 2014, 05:18:21 PM
Watching this topic with some interest.
A question for all you guys. Has anyone heard a decent (and by decent I mean nearly as good as a
dedicated transport/DAC or well sorted analogue system) reasonably priced PC based audio system.
Has anyone heard a decent PC based music system at any price?

If you have had experience with either system, has this system been used successfully for a reasonable
period of time without constant pissing around with both the software and the hardware, ie complete and
going reliably without any modifications for six months or more?

Is it a mandatory and expected fact that if you use a PC for digital audio you are committing to using most
of your listening time fcuking about with useless sh!t equipment and crap technology designed for a totally
different purpose. If I want a piece of toast I put it in the toaster not the bloody washing machine.  :D

Do you really believe a $99.00 kit board solution will be the answer to all your digital dreams? or are you
all deluded?  :-*
Ha,,, its all true, but we hope to change that. The best computer audio I have heard was at my place and that was a very expensive full on rig. He had been working on it's sound for about 5 years, and spent loads of money, it was very good, not like real, but very good. Where it fell down was the typical problems that seem to be intrinsic in all the computer based transport systems i have heard, a slightly White, thin, anaemic, and cold unmusical artificial nature, not much flesh on that bone. Yes unfortunately it was only ok in all the areas that really matter. On the plus side when i removed this $10,000 latest and greatest 24 bit 192 dac and plugged it into my Killerdac via a digital cable, the improvement was dramatic. Can we make a computer interface that cuts it, well that is the plan, but my modified Wadia 3200 killerdac combo is so good, its very unlikely i can reach that level, but even if i can get 90 precent i will be happy, maybe. Ultimately can we have brilliance via computer audio, probably not. Why? the simple answer could be. That Less is More. For people who don't know what that means, the less sh!t or complexity your system has, the better it can potentially sound. The other problem may be the poor sounding chips they use.
Title: Re: Computer transport interface
Post by: Tuyen on May 25, 2014, 05:54:10 PM
Thanks for sharing your experience, Steven.  I was told many a time you are a man who will only accept brilliance.  If this is true, the very nature of computer audio being how complex it is, I can't see how it would ever make you happy?  There would be too many compromises!    Life's too short to even bother getting worked into it if one isn't truly interested or believe in the concept or idea of computer audio. Would just continually be disappointed. Which was one of my main point before. Would you tend to agree?
Title: Re: Computer transport interface
Post by: stevenvalve on May 25, 2014, 07:31:16 PM
Thanks for sharing your experience, Steven.  I was told many a time you are a man who will only accept brilliance.  If this is true, the very nature of computer audio being how complex it is, I can't see how it would ever make you happy?  There would be too many compromises!    Life's too short to even bother getting worked into it if one isn't truly interested or believe in the concept or idea of computer audio. Would just continually be disappointed. Which was one of my main point before. Would you tend to agree?
Tuyen you have built so many different systems over the years, and no doubt like all of us have spent plenty of money, The fanatical one, Bryan in Melbourne has built about the same amount of systems, because he is a man who will only accept brilliance, I think he holds the record closely followed by you. Tuyen that also means that you are a man who will only accept brilliance. I have had the same general System for about 20 years. For many years I never used digital, because digital sucked, I only played turntable, but I decided I will try to make digital happen after hearing the potential of a full on all battery powered burr brown chipped dac built by Zenelectro. Today we have the killerdac, finally we have digital that really makes music, Why then can't we take computer transports, put in the effort, and hopefully also make music. whether or not its possible time will tell, but we need to waste our short lives on something. I am really worried about the modern chips being the bottle neck, and those surface mount resistors, YUK. 
Title: Re: Computer transport interface
Post by: zenelectro on May 25, 2014, 10:37:38 PM
Doesnt loading the oscillator ensure a tighter square wave?

What is the theory in loading it?

The load is acting on the sine wave oscillator before the squaring circuit.

Supposedly the oscillator should meet its spec with any load down to a few hundred ohms but I did notice
the load makes a big difference to the sine wave OP level.  IOW, when 'unoading' the oscillator, the amplitude
gets larger. Remember I am referring to the sine wave OP pre squaring.

So despite what the so called specs say it all appears very interactive. I got best results with the lightest
possible load.

T
Title: Re: Computer transport interface
Post by: zenelectro on May 25, 2014, 11:18:55 PM
Tuyen you have built so many different systems over the years, and no doubt like all of us have spent plenty of money, The fanatical one, Bryan in Melbourne has built about the same amount of systems, because he is a man who will only accept brilliance, I think he holds the record closely followed by you. Tuyen that also means that you are a man who will only accept brilliance. I have had the same general System for about 20 years. For many years I never used digital, because digital sucked, I only played turntable, but I decided I will try to make digital happen after hearing the potential of a full on all battery powered burr brown chipped dac built by Zenelectro. Today we have the killerdac, finally we have digital that really makes music, Why then can't we take computer transports, put in the effort, and hopefully also make music. whether or not its possible time will tell, but we need to waste our short lives on something. I am really worried about the modern chips being the bottle neck, and those surface mount resistors, YUK.

Steven,

Yes agreed, all these DAC's are way too complex.

My next DAC for PC playback will not use any commercial DAC chip or digital filter end of story. It will be a fully discrete DAC and designed from ground up with the highest quality logic, clocks,
thru hole parts etc. You can use whatever resistors you like :) WRT less is more, yes, that is why I am going this way. The tricky part is circuit board layout however I have a pretty good
handle on that with a simple noise cancelling balanced architecture. 

That's about all I can say at this stage.

Z
Title: Re: Computer transport interface (some ppl make $$$ on cd players
Post by: kajak12 on May 25, 2014, 11:31:21 PM
http://www.6moons.com/audioreviews2/neodio/1.html

AT 38K (US) CHECK WHATS INSIDE!!!!!!   makes computer audio very cheap
Title: Re: Computer transport interface
Post by: Rob181 on May 26, 2014, 06:56:52 AM
Steven,

Yes agreed, all these DAC's are way too complex.

My next DAC for PC playback will not use any commercial DAC chip or digital filter end of story. It will be a fully discrete DAC and designed from ground up with the highest quality logic, clocks,
thru hole parts etc. You can use whatever resistors you like :) WRT less is more, yes, that is why I am going this way. The tricky part is circuit board layout however I have a pretty good
handle on that with a simple noise cancelling balanced architecture. 

That's about all I can say at this stage.

Zen...I will be watching this with interest...more than interest...very keen to see/hear this DAC...

Z
Title: Re: Computer transport interface
Post by: ozmillsy on May 26, 2014, 10:42:37 AM
The load is acting on the sine wave oscillator before the squaring circuit.

Supposedly the oscillator should meet its spec with any load down to a few hundred ohms but I did notice
the load makes a big difference to the sine wave OP level.  IOW, when 'unoading' the oscillator, the amplitude
gets larger. Remember I am referring to the sine wave OP pre squaring.

So despite what the so called specs say it all appears very interactive. I got best results with the lightest
possible load.
I wonder if our (longer than recommended) i2s connections are part of this?
 
Title: Re: Computer transport interface
Post by: gamve on May 26, 2014, 11:34:43 AM
Bargain at $380.00. Not sure what you get for the other 37K.  ;D
Title: Re: Computer transport interface
Post by: zenelectro on May 26, 2014, 06:15:53 PM
I wonder if our (longer than recommended) i2s connections are part of this?
 

No, that should not have anything to do with it. The clock does not drive the I2S directly.

I had plans to do an I2S driver integrated on the zenclock board but I'm not sure it's worth the hassle.

How many people would be interested in this?

There are many things happening ATM, not the least health issues. Full on year to say the least :)




Title: Re: Computer transport interface
Post by: ozmillsy on May 26, 2014, 06:18:58 PM
Nah, we've already got great performance, not worth the hassle.
Title: Re: Computer transport interface
Post by: zenelectro on May 26, 2014, 06:20:26 PM
Bargain at $380.00. Not sure what you get for the other 37K.  ;D

Graham - this is the hi end mate, the more things change, the more they stay the same! :)

Cast your memory back to products like Forsell air reference CD transport. They were -very- expensive, I've had one here apart,
you would be cringing at what you get for the money.  A decent clocked, I2S OP CD 94 would leave it in the dust at tiny fraction of the price.

Z
Title: Re: Computer transport interface
Post by: kajak12 on May 26, 2014, 11:36:16 PM
No, that should not have anything to do with it. The clock does not drive the I2S directly.

I had plans to do an I2S driver integrated on the zenclock board but I'm not sure it's worth the hassle.

How many people would be interested in this?

There are many things happening ATM, not the least health issues. Full on year to say the least :)


Z
I2s driver i will have one  :-*
Title: Re: Computer transport interface
Post by: ozmillsy on May 27, 2014, 09:38:21 AM
I2s driver i will have one  :-*
Danny added a I2S output mod to my CD94,  because I insisted on proper CD94->Dac cabling  (not loose wires, I have kids who like to yank at wires).       If signal strength is a concern, then Danny's mod is an option. 

I don't think we can say the long wire run is out of the picture.   The whole chain is in the mix (right back to choice of CD-R and burner).     But there is probably bigger fish to fry than focussing any more time on optimising the I2S part of the chain.   :)
Title: Re: Computer transport interface
Post by: zenelectro on May 27, 2014, 12:08:35 PM
Danny added a I2S output mod to my CD94,  because I insisted on proper CD94->Dac cabling  (not loose wires, I have kids who like to yank at wires).       If signal strength is a concern, then Danny's mod is an option. 

I don't think we can say the long wire run is out of the picture.   The whole chain is in the mix (right back to choice of CD-R and burner).     But there is probably bigger fish to fry than focussing any more time on optimising the I2S part of the chain.   :)

WRT clock loading versus versus I2S cable driving, they are 2 separate things and not really directly interactive.

WRT your I2S cable drivers, in the scheme of things I don't know that it brings much to the party. 
The I2S signal needs to be directly reclocked by the oscillator and as such ideally put on the clock board.

A zenclock would have maybe 10 to 100 x lower jitter than the I2S generating circuitry in CD94. 
So in effect the re clocked I2S driver board may well be a bigger improvement than the clock itself.

There are other issues:

a) 5V logic level is not optimum for feeding I2S of TDA1541
b) There are many different types of logic for driving I2S, some noisier than others. Finding information on jitter
generated by various logic types is very difficult. I've built up  a data base of info on this stuff but it took a lot of
research.

As you can see it's just not quite as simple as first appears.

OK that's enough information for one post - and enough time wasted. Too much to do atm. :)


Title: Re: Computer transport interface
Post by: ozmillsy on May 27, 2014, 12:55:34 PM
A zenclock would have maybe 10 to 100 x lower jitter than the I2S generating circuitry in CD94. 
So in effect the re clocked I2S driver board may well be a bigger improvement than the clock itself.
Yeah, maybe,,,,, I see your point.   

Put it this way,  the Zenclock into Dannys i2s mod already sounds sooooooo freaking good,  I am loath to change anything about it.   I don't even want to mount the bl00dy thing,  I'm leaving it on that old dirty rag,  because what I have right now is *magic*.   ;)

I still do reckon there are much bigger fish to fry.   
Title: Re: Computer transport interface
Post by: zenelectro on May 27, 2014, 01:00:09 PM
Yeah, maybe,,,,, I see your point.   

Put it this way,  the Zenclock into Dannys i2s mod already sounds sooooooo freaking good,  I am loath to change anything about it.   I don't even want to mount the bl00dy thing,  I'm leaving it on that old dirty rag,  because what I have right now is *magic*.   ;)

I still do reckon there are much bigger fish to fry.

And only so much time!  :)



Title: Re: Computer transport interface
Post by: kajak12 on May 27, 2014, 06:26:04 PM
Danny added a I2S output mod to my CD94,  because I insisted on proper CD94->Dac cabling  (not loose wires, I have kids who like to yank at wires).       If signal strength is a concern, then Danny's mod is an option. 

I don't think we can say the long wire run is out of the picture.   The whole chain is in the mix (right back to choice of CD-R and burner).     But there is probably bigger fish to fry than focussing any more time on optimising the I2S part of the chain.   :)
i run loose cat 5 wires why? because they are better then coaxial,i also have a 4 year old  trained not to touch my system (so far so good fingers crossed)
Regarding zen reclocking i have nothing to loose its part of the journey i dont spend much on hifi so why not give some to ZEN PTY LTD.
as for bigger fish they will come after entree.
ZEN GET TO WHEN POSSIBLE YOU HAVE A KEEN CUSTOMER I KNOW WHAT YOUR CLOCK DONE SO ANYTHING ELSE IS A BIG FISH FOR ME.
Title: Re: Computer transport interface
Post by: stevenvalve on May 31, 2014, 10:02:46 PM
When I get it, I will initially be trying it out for DSD audio. I will integrate it in with my Pioneer DV-989AVi which I modified for 2 channels only. I'll use the DAC in it to stream DSD. It has quite a reasonable BB DAC (PCM1738E) with an analogue stage that's been modified with OPA627's and 2SK170/2SJ74 complementary FET output.
Should be quite interesting.

I imagine the USBtoI2S board will have plenty of potential for upgrade tinkering, especially in the clock re-generators.

Hope to get it soon.  :D

p.s. The board is available from this site too: http://jlsounds.com/products.html
What does it sound like.
Title: Re: Computer transport interface
Post by: dannydigital on May 31, 2014, 10:36:26 PM
I got it! (Yesterday)

Stayed up till almost dawn tinkering. I got it to work in my Pioneer 989 after a few teething problems with the DAC's DSD configuration and the system muting.
I found that the USB board had to be on-line first for the DAC to configure to DSD, not too sure why since the serial config interface of the DAC is asynchronous to the audio bit clock?
Also I had to kill the players system muting in order to O/P the sound. I can control the muting with the DSD flag pin on the USB board but it's not quite 100% the way it should work.
At the moment it's just a crude setup and good for audio evaluation and I must say that it's looking very promising considering I'm only using the laptop's USB to power the board (not taking advantage of the galvanic isolation), to me this DSD sounds pretty good! (Using a modified Marantz SC-8 as a headphone amp. + Sennheiser HD650's)  :o

D
Title: Re: Computer transport interface
Post by: ozmillsy on May 31, 2014, 10:38:54 PM
Good news Danny,  following with interest.
Title: Re: Computer transport interface
Post by: ozmillsy on June 01, 2014, 09:53:05 AM
Danny,  just to be clear on what you've done for all forum members.    You have used this board to add a USB interface to your Pioneer player, essentially turning it into a standalone DAC that can be fed by a computer source.

What this allows you to do,  is playback DSD files on your computer,   bitstream the data to your Pioneer over USB,   and let your Pioneer handle the DAC duties.

Because it's a multi-format player,  you can also bitstream any other source format file. 

Once you sort out the teething issues.   You can offer this mod to anyone who has a hi-res disc spinner, and they want to start using a computer source via USB.   Correct?
Title: Re: Computer transport interface
Post by: kajak12 on June 01, 2014, 11:29:57 AM
I got it! (Yesterday)

Stayed up till almost dawn tinkering. I got it to work in my Pioneer 989 after a few teething problems with the DAC's DSD configuration and the system muting.
I found that the USB board had to be on-line first for the DAC to configure to DSD, not too sure why since the serial config interface of the DAC is asynchronous to the audio bit clock?
Also I had to kill the players system muting in order to O/P the sound. I can control the muting with the DSD flag pin on the USB board but it's not quite 100% the way it should work.
At the moment it's just a crude setup and good for audio evaluation and I must say that it's looking very promising considering I'm only using the laptop's USB to power the board (not taking advantage of the galvanic isolation), to me this DSD sounds pretty good! (Using a modified Marantz SC-8 as a headphone amp. + Sennheiser HD650's)  :o

D
Good to see you know what you are doing if it was me it would be fried by now
Title: Re: Computer transport interface
Post by: dannydigital on June 01, 2014, 01:53:39 PM
Danny,  just to be clear on what you've done for all forum members.    You have used this board to add a USB interface to your Pioneer player, essentially turning it into a standalone DAC that can be fed by a computer source.

Yes, and to still be able to use the player for spinning discs by incorporating a digital line switch. (ie. Discs / USB function)

What this allows you to do,  is playback DSD files on your computer,   bitstream the data to your Pioneer over USB,   and let your Pioneer handle the DAC duties.

Correct.

Because it's a multi-format player,  you can also bitstream any other source format file.
 

Perhaps in the future as this requires a more complicated mod for configuring the DAC into the required modes.

At the moment I use an SACD disc to spin-up in the player in order to configure the DAC into DSD mode. (this is quite simple)

Once you sort out the teething issues.   You can offer this mod to anyone who has a hi-res disc spinner, and they want to start using a computer source via USB.   Correct?

I can offer some help but note that every player can be quite different.

Potentially the plan would be to use this board to build a multi-format "murderDAC!" (USB version) from ground up.   :o :P

D
Title: Re: Computer transport interface
Post by: ozmillsy on June 01, 2014, 02:51:13 PM
LMAO,    I like it.    ;)

Title: Re: Computer transport interface
Post by: gamve on June 02, 2014, 12:47:03 PM
Then when it is all sorted we can have an "AssasinDAC"   :o
Title: Re: Computer transport interface
Post by: ozmillsy on June 02, 2014, 06:03:09 PM
SerialKiller?
Title: Re: Computer transport interface
Post by: kajak12 on June 02, 2014, 07:58:46 PM
SerialKiller?
serial killer=  16 bit,24bit,32bit and dsd and 2xdsd
Title: Re: Computer transport interface
Post by: ozmillsy on June 02, 2014, 08:04:46 PM
I'd be happy with pure dsd.

Title: Re: Computer transport interface
Post by: Tuyen on June 03, 2014, 12:14:27 AM
Running the USB module from it's own dedicated power supply should bring quite a dramatic improvement in SQ compared to being powered by the USB bus!  Keen to read what sort of power supply design you find sounds best powering the USB-I2S module.

Though in saying that,  one might first question your hearing, writing that a Delta Sigma based DAC sounds 'pretty good'?    I thought there was a common law on this forum that states that Delta Sigma based DACs wash the naturalness, timbre, heart and soul out of the music.    What then is the point of listening to the music at all, one may ask?  8)
Title: Re: Computer transport interface
Post by: stevenvalve on June 03, 2014, 12:37:04 AM
?    I thought there was a common law on this forum that states that Delta Sigma based DACs wash the naturalness, timbre, heart and soul out of the music.    What then is the point of listening to the music at all, one may ask?  8)
I have found that all the newer chips i have heard do that. Burr brown chips could be good, anyone know.
Title: Re: Computer transport interface
Post by: Tuyen on June 03, 2014, 07:11:18 AM
My experience too Steven.  I've found only when the BB chips were configured to run in NOS (non oversampling) mode, did it start to get some life back into the music!

Happy to be proven wrong!  :-[
Title: Re: Computer transport interface
Post by: ozmillsy on June 03, 2014, 08:44:05 AM
Haha, you're such a tease Tuyen. :)

There are multibit fanbois zealots over on SNA, no doubt.

Most of the old timers here are more open minded, in my observation.     

The issue is, to extract the level of performance we expect out of any dac chip, involves significant effort (if not years of development).

The reality is, tda1541a stocks are dwindling.   The chips are not getting any cheaper.   We need another solution.

Here's a thought, maybe we should be pursue'ing a dac that has no chip?    :o
Title: Re: Computer transport interface
Post by: gamve on June 03, 2014, 11:41:32 AM
Haha, you're such a tease Tuyen. :)

There are multibit fanbois zealots over on SNA, no doubt.

Most of the old timers here are more open minded, in my observation.     

The issue is, to extract the level of performance we expect out of any dac chip, involves significant effort (if not years of development).

The reality is, tda1541a stocks are dwindling.   The chips are not getting any cheaper.   We need another solution.

Here's a thought, maybe we should be pursue'ing a dac that has no chip?    :o

Or taken one step further
"Perhaps we should be giving up on digital audio altogether"  :o
Title: Re: Computer transport interface
Post by: zenelectro on June 03, 2014, 12:17:17 PM
Or taken one step further
"Perhaps we should be giving up on digital audio altogether"  :o

Analog is for the weak who have no true resolve.  :D :D :D

Title: Re: Computer transport interface
Post by: springcreek on June 03, 2014, 12:27:30 PM
Come and join me on the dark side (black disk), it's quite cosy over here  ;)
Title: Re: Computer transport interface
Post by: Tuyen on June 03, 2014, 03:16:40 PM
dannydigital, may I please ask where you are sourcing the DSD files you are listening to from?   :-*
Title: Re: Computer transport interface
Post by: gamve on June 03, 2014, 03:34:38 PM
Analog is for the weak who have no true resolve.  :D :D :D

Hey Zen,
I was going to comment but could not decide if you wanted a proper response or an interpolated response  :P
Title: Re: Computer transport interface
Post by: Rob181 on June 03, 2014, 05:30:04 PM
Come and join me on the dark side (black disk), it's quite cosy over here  ;)
I'm there...life is easy...great musical reproduction is somewhat more challenging...
Title: Re: Computer transport interface
Post by: ozmillsy on June 03, 2014, 06:56:45 PM
dannydigital, may I please ask where you are sourcing the DSD files you are listening to from?   :-*

He gets them from here,,,,,

http://store.acousticsounds.com/c/372/DSD (http://store.acousticsounds.com/c/372/DSD)

 8)  :P
Title: Re: Computer transport interface
Post by: dannydigital on June 05, 2014, 04:09:16 PM
dannydigital, may I please ask where you are sourcing the DSD files you are listening to from?   :-*

Or here http://rutracker.org/ if you dare.  :-X
Title: Re: Computer transport interface
Post by: dannydigital on June 05, 2014, 05:03:52 PM
That's it Danny. :)

I just bought one myself. Should be a good project.
Getting re familiarized with Design Spark.   

T

Hey Terry,

Have you got your board yet?  I'm wondering if you will be trying it with DSD.

I'm finding the board to sound quite nice, but there are some bugs I'm trying to iron-out. One thing I noticed is that it's got a nasty glitch/pop in the left channel the moment you press play or track next/previous, quite annoying!
Also, the "DSD flag" (P8) and "codec reset" (P7) resets during louder passages of DSD signal. This is not so good if you want to use those pins for system muting.
I read something interesting on the web site that Andrew posted earlier which could be related to this issue with peaking. See here, [http://store.acousticsounds.com/d/94956/Michael_Jackson-Thriller-DSD].  There is, "A NOTE ABOUT DSD AUDIO LEVEL".
I'm thinking that this could be a driver or firmware issue that would need to be worked on to process an extra +3dB DSD peak correctly?

I'll be interested in your experience, hoping mine is not a H/W fault. :-\

D
Title: Re: Computer transport interface
Post by: zenelectro on June 05, 2014, 07:05:17 PM
Hey Terry,

Have you got your board yet?  I'm wondering if you will be trying it with DSD.

I'm finding the board to sound quite nice, but there are some bugs I'm trying to iron-out. One thing I noticed is that it's got a nasty glitch/pop in the left channel the moment you press play or track next/previous, quite annoying!
Also, the "DSD flag" (P8) and "codec reset" (P7) resets during louder passages of DSD signal. This is not so good if you want to use those pins for system muting.
I read something interesting on the web site that Andrew posted earlier which could be related to this issue with peaking. See here, [http://store.acousticsounds.com/d/94956/Michael_Jackson-Thriller-DSD].  There is, "A NOTE ABOUT DSD AUDIO LEVEL".
I'm thinking that this could be a driver or firmware issue that would need to be worked on to process an extra +3dB DSD peak correctly?

I'll be interested in your experience, hoping mine is not a H/W fault. :-\

D

Danny,

I should get mine in a week or so. There are numerous issues WRT pops etc with DSD but there are work arounds.
The other card is Amanero which I believe is superior but it has no galv isolation and there are various add on
isolation boards available = more time and stuffing around.

WRT DSD levels, if you are referring to the 'modulation index' it should be 50%, meaning at full signal the DSD filtered level should swing
half the 0 to rail level. So I'm guessing if you just low passed the DSD stream, and the logic swing was 0 to 4V, then the 0dBFS would swing
from +1V to +3V = 2V peak. However I have not tried this.

I'm thinking there will be some work arounds in our future.

Z
 
Title: Re: Computer transport interface
Post by: stevenvalve on June 24, 2014, 07:21:29 PM
Danny arrived with Williams just finished and much modified Marantz 94 player. It has a reclocker fitted to the output driving the Clock, word, data. Interesting it sounded good, but the improvement when we changed it to run my battery to power the clock was dramatic, amazing really. You can hear a course grainy roughness when its connected via its internal power but with just the clock attached to a battery, WoW  Smooth sophisticated classy, For some people hard to believe, but true.   
Title: Re: Computer transport interface
Post by: stevenvalve on June 24, 2014, 07:24:39 PM
More pictures
Title: Re: Computer transport interface
Post by: stevenvalve on June 24, 2014, 07:30:08 PM
Danny also brought along his computer transport Direct DSD Board fitted into his modified pioneer player. Its full on, I think danny can explain its workings.
Title: Re: Computer transport interface
Post by: Tuyen on June 24, 2014, 07:43:59 PM
Progress!  I like it!
Title: Re: Computer transport interface
Post by: ozmillsy on June 24, 2014, 08:08:26 PM
Danny,  if you are around, can you clarify what Steven means by 'reclocker' ?

I assume this is something different to the buffer inside my transport that drives the i2s outputs?
Title: Re: Computer transport interface
Post by: brenden on June 24, 2014, 11:46:17 PM
I just noticed the clock in the CD94.Its the same clock  that I am using from Valab .This clock is an excellent value for around $50 .I  really think the clock  would benefit from bigger and better filter caps ,and intend to try a couple of my favourite Elnas ,off board .I don't have it running from a battery ,but used to run my first CD94 mk2 clock with a battery  about 15 years ago ,until I had to pack it away about 6 years ago .It was more pure with battery for sure .

    I have actually  bought another couple of these clocks .One for a mate  ,and one for my CD12 .
 
         
Title: Re: Computer transport interface
Post by: stevenvalve on June 25, 2014, 12:07:53 AM
The battery to run the clock (12Volt) was not a little better, I was amazingly better. There is just to much noise in the transport power supply.
Title: Re: Computer transport interface
Post by: brenden on June 25, 2014, 07:32:10 AM
Yeah  Steven , it was such a long time ago , I prefer to err on the side of caution with my claims.

   To  lessen the chance of noise I run separate wires  from the clock to the transformer for  power  ,instead of trying to tap one of the other boards .
         I will improve the power capacitance to the clock before comparing to battery again  as  its probably more critical when using AC ..I still think the battery will be superior but I think the gap can be lessenned .
 
    I also run separate ground wires from the  vertical filter board  direct to the transformer  and also  from the dac board  to transformer on the mk2  to  lessen contamination. The quality and sizing of the wires makes a big difference too.
      The grounding  arrangements  on the Marantz  dont  appear  to be as good as they could be  , probably for convenience . Cheers .
Title: Re: Computer transport interface
Post by: Jehuty on June 25, 2014, 07:14:46 PM
Danny arrived with Williams just finished and much modified Marantz 94 player. It has a reclocker fitted to the output driving the Clock, word, data. Interesting it sounded good, but the improvement when we changed it to run my battery to power the clock was dramatic, amazing really. You can hear a course grainy roughness when its connected via its internal power but with just the clock attached to a battery, WoW  Smooth sophisticated classy, For some people hard to believe, but true.
Far out Steve, I didn't even know my transport was going to your place and now you are tempting me to mod my CD94 further with battery power supply. Decision....decision....nah, I'll spend my money on tapes  :P

I just noticed the clock in the CD94.Its the same clock  that I am using from Valab .This clock is an excellent value for around $50 .
I bought it based on your suggestion Brenden, so thanks again  :)

Danny,  if you are around, can you clarify what Steven means by 'reclocker' ?

I assume this is something different to the buffer inside my transport that drives the i2s outputs?
I would be surprised if it's different to your buffer Oz because that's what I asked Danny to do.
Title: Re: Computer transport interface
Post by: ozmillsy on June 25, 2014, 08:08:06 PM
I would be surprised if it's different to your buffer Oz because that's what I asked Danny to do.
Ahh, ok.  The reclocker term threw me a bit.   No worries.  So are you doing bare i2s wires from output buffer to receiver chip input socket,  or are you using cables?

Btw, you dont need a big car battery.  You should still get a good improvement with smaller batteries, which tuck away more easily.
Title: Re: Computer transport interface
Post by: Jehuty on June 25, 2014, 08:22:22 PM
Ahh, ok.  The reclocker term threw me a bit.   No worries.  So are you doing bare i2s wires from output buffer to receiver chip input socket,  or are you using cables?

Btw, you dont need a big car battery.  You should still get a good improvement with smaller batteries, which tuck away more easily.
I've been using ICs just like yours. I can't stand the mess of bare wires. Yep, asking Danny to use battery power supply now, hopefully it can be done without too much trouble. I do have a battery powered valve preamp so I'll probably need to get a bigger battery...
Title: Re: Computer transport interface
Post by: dannydigital on June 26, 2014, 12:59:00 AM
Hi everyone,

I just managed to squeeze in some online time here in Port Douglas, truly an amazing part of the world.
Thought I should straighten up some things about the work on Williams player.

Ahh, ok.  The reclocker term threw me a bit.   No worries.  So are you doing bare i2s wires from output buffer to receiver chip input socket,  or are you using cables?


The setup is one I haven't implemented before which buffers and also reclocks the I2S o/p, therefore the reason for trying it out at Steves. I wanted to make sure it functioned well without any unwanted  surprises and evaluate it's sound with at least four ears.
As Steve mentioned earlier, we did notice quite an improvement when the clock board was powered externally with the battery. This makes sense not only because it is a cleaner source of power but it also eliminates having a ground loop when powered internally. Basically the cleaner the power to the clock the lower the jitter in its pulse (edge), which when presented for reclocking can make quite a noticable outcome as it is the last active stage before the DAC.
So William a good surprise, you can have this little bonus for no extra charge, we can call it a bit of R&D. And yes I can do the external power mod for you.

Cheers to all from up north  8)

D
Title: Re: Computer transport interface
Post by: Jehuty on June 26, 2014, 06:01:13 AM
Thanks Daniel. I'll get the player once you done the mod.

Cheers.
Title: Re: Computer transport interface
Post by: Jehuty on June 26, 2014, 05:07:13 PM
The battery to run the clock (12Volt) was not a little better, I was amazingly better. There is just to much noise in the transport power supply.

Hi Steve, is this your battery?
(http://s28.postimg.org/n832gvs55/Supercharge_GOLD_MF43_1_1.jpg) (http://postimg.org/image/n832gvs55/)

I found it here: http://www.supercharge.com.au/car-batteries/supercharge-gold-plus
Title: Re: Computer transport interface
Post by: stevenvalve on June 26, 2014, 07:59:07 PM
This is the best sounding clock battery i have heard to date. It has body and warmth without the grain of a lead acid battery. Its the only one that outperforms the small batterys, including the best rechargables..
Title: Re: Computer transport interface
Post by: Jehuty on June 26, 2014, 08:19:36 PM
This is the best sounding clock battery i have heard to date. It has body and warmth without the grain of a lead acid battery. Its the only one that outperforms the small batterys, including the best rechargables..

Looks like it's the older version of the one I found. Dammit. Don't tell me the price is going up like those NOS valves....

Found it here: http://www.autobarn.com.au/supercharge-automotive-battery-gold-mf52
Title: Re: Computer transport interface
Post by: stevenvalve on June 26, 2014, 08:31:36 PM
That's it, now do they actually have them.
Title: Re: Computer transport interface
Post by: Jehuty on July 12, 2014, 03:40:11 PM
Danny arrived with Williams just finished and much modified Marantz 94 player. It has a reclocker fitted to the output driving the Clock, word, data. Interesting it sounded good, but the improvement when we changed it to run my battery to power the clock was dramatic, amazing really. You can hear a course grainy roughness when its connected via its internal power but with just the clock attached to a battery, WoW  Smooth sophisticated classy, For some people hard to believe, but true.

Okay I got my CD94 transport back from Danny Digital.

Running it straight cold with KillerDAC using just a Jaycar sealed lead acid battery (it's all I got for now), how's the sound? Well, my system never sounded this good! It feels like a veil has been lifted giving a true and honest presentation of the music with tone, texture, timing and rythym fall into place together, very coherent! And just like Steve said, grainless and sophisticated. I can't stop smiling from ear to ear. Well done Danny Digital!  ;D ;D ;D
Title: Re: Computer transport interface
Post by: brenden on July 12, 2014, 04:41:02 PM
I used to use a couple of 6 volt lantern batteries(I used to get them real cheap ) on my CD94 11   to a Trichord  ,So I know the excitement you are feeling Jehuty .

     There were no down sides to running a clock with batteries .Everything was better . I loved the purity ,and when you run electrostatics ,any grain or grit is very apparent .
                I also found that I could listen to more marginal sounding  CDs  with a battery powered clock .

            I often read about  people criticising modding, saying that you can only listen to well recorded CDs ,and less well recorded CDs become unlistenable ,but if you reduce distortions and noise from the playback chain ,then most or all  CDs  should sound better .
     If I do a mod ,I want it to sound better across the board ,or at least do something better ,with no other down sides .
             We should all be running battery powered clocks .The Valab is an excellent value clock probably due to better regulation than the Trichords ,and it is critical .Valab  also have a higher tolerance crystal ,but I don't know if there is any advantage over the one they put into their clock .
               Next stage for me is to get hold of a zen clock once Zenelectro  is  back on board .
     
   Any photos of the finnshed CD94 Jehuty ?

     
         
Title: Re: Computer transport interface
Post by: Jehuty on July 12, 2014, 04:58:38 PM
Will post some pictures tomorrow  :)
Title: Re: Computer transport interface
Post by: ozmillsy on July 13, 2014, 11:45:11 AM
Okay I got my CD94 transport back from Danny Digital.

Running it straight cold with KillerDAC using just a Jaycar sealed lead acid battery (it's all I got for now), how's the sound? Well, my system never sounded this good! It feels like a veil has been lifted giving a true and honest presentation of the music with tone, texture, timing and rythym fall into place together, very coherent! And just like Steve said, grainless and sophisticated. I can't stop smiling from ear to ear. Well done Danny Digital!  ;D ;D ;D
Now you get to enjoy your CD collection in a whole new light.

It's great when we make a big stride forward.
Title: Re: Computer transport interface
Post by: Jehuty on July 13, 2014, 09:05:23 PM
Pics as promised:
(http://s27.postimg.org/ddyiz2f5b/2014_07_13_20_42_15.jpg) (http://postimg.org/image/ddyiz2f5b/)

Close up:
(http://s22.postimg.org/vkqxsqv3x/2014_07_13_20_41_32.jpg) (http://postimg.org/image/vkqxsqv3x/)
Title: Re: Computer transport interface
Post by: brenden on July 13, 2014, 09:42:29 PM
Thanks Jehuty.
  I see your clock has the higher grade crystal already. Mine has the .1ppm part.

       Can I ask what the RCA outputs are connected to ?
Title: Re: Computer transport interface
Post by: Jehuty on July 13, 2014, 11:01:11 PM
Can I ask what the RCA outputs are connected to ?

Hi Brenden, those are my preferred I2S connections because I don't want a messy CAT5 wires  ;)
Title: Re: Computer transport interface
Post by: kajak12 on July 14, 2014, 07:23:55 PM
Hi Brenden, those are my preferred I2S connections because I don't want a messy CAT5 wires  ;)
Your killing the sound usinG rca plugs on I2S
Title: Re: Computer transport interface
Post by: ozmillsy on July 14, 2014, 08:14:40 PM
Mario, have you listened to Danny's i2s driver mod yet?
Title: Re: Computer transport interface
Post by: Jehuty on July 15, 2014, 03:46:24 PM
Your killing the sound usinG rca plugs on I2S

Maybe, there are compromises which I have to live with  ;)
Title: Re: Computer transport interface
Post by: Tuyen on July 22, 2014, 04:24:55 PM
Hi Danny, how are you finding the USB-I2S module now that you have been running it for past few weeks?

Have you received yours Terry?
Title: Re: Computer transport interface
Post by: dannydigital on July 24, 2014, 06:25:54 PM
Hi Tuyen,

I haven't been playing the usb device at the moment as I've been setting up a long anticipated vinyl system.
I'm hoping to pick up on it in the next coming weeks though as I want to include it in my system to compare or use the vinyl as a reference to compare and tweak with the DSD playback of the usb unit.

Cheers,
D
Title: Re: Computer transport interface
Post by: ozmillsy on July 25, 2014, 04:06:25 PM
I haven't been playing the usb device at the moment as I've been setting up a long anticipated vinyl system.
I'm hoping to pick up on it in the next coming weeks though as I want to include it in my system to compare or use the vinyl as a reference to compare and tweak with the DSD playback of the usb unit.
Hey Danny,  out of curiosity,  what is your approach for making those comparisons?

Do you have a reference vinyl title, and same title in DSD.    Or do you record the vinyl and playback?

What are you using?
Title: Re: Computer transport interface
Post by: Jehuty on July 25, 2014, 04:48:09 PM
What are you using?

Marantz for sure  8)

Yeah, I am keen to see (and listen) his setup too. Based on what he told me last time, I think it would be a very nice setup  :)
Title: Re: Computer transport interface
Post by: Tuyen on October 07, 2014, 01:56:05 PM
Hi Tuyen,

I haven't been playing the usb device at the moment as I've been setting up a long anticipated vinyl system.
I'm hoping to pick up on it in the next coming weeks though as I want to include it in my system to compare or use the vinyl as a reference to compare and tweak with the DSD playback of the usb unit.

Cheers,
D

Hi Danny,

Any updates?    ;D
Title: Re: Computer transport interface
Post by: kajak12 on November 30, 2014, 12:00:22 PM
http://www.audialonline.com/online-topics/tda1541a-and-model-s-usb-part-1-192-khz/

who is first to buy
Title: Re: Computer transport interface
Post by: rab on December 05, 2014, 07:57:13 PM
http://www.audialonline.com/online-topics/tda1541a-and-model-s-usb-part-1-192-khz/

who is first to buy

I already bought one of Pedja's new boards... unpopulated. I have also bought a board that will allow me to use simultaneous data mode.

I am looking forward to putting it all together.

p.s. Mick Moloney has already done this.

- r.

Title: Re: Computer transport interface
Post by: kajak12 on December 05, 2014, 10:13:22 PM
I already bought one of Pedja's new boards... unpopulated. I have also bought a board that will allow me to use simultaneous data mode.

I am looking forward to putting it all together.

p.s. Mick Moloney has already done this.

- r.
Aware that mick has done this wondering why no body on this forum hasn't done it
Title: Re: Computer transport interface
Post by: Rob181 on December 05, 2014, 10:50:45 PM
I don't see what all the fuss is about...

You cannot have a 1541 in the one box does both native streaming & 192...

I am resigned to having an I2S KD & something else for computer streaming...
Title: Re: Computer transport interface
Post by: rab on December 06, 2014, 01:32:49 PM
Well, we're talking about the "something else"...!
Title: Re: Computer transport interface
Post by: Rob181 on December 06, 2014, 10:12:09 PM
Fair enough...

I will wait for Zen moment...
Title: Re: Computer transport interface
Post by: Jehuty on December 06, 2014, 10:14:50 PM
Fair enough...

I will wait for Zen moment...

Hi Rob,

Are you not going to get the Amanero with Clay's power supply? I spoke to Craig last night and he's indeed impressed with it, finally there's some hope for a computer transport...

Cheers,
Wil
Title: Re: Computer transport interface
Post by: Rob181 on December 06, 2014, 10:22:21 PM
Wil...

I have not heard it or benchmarked it with anything else...

I will wait until my Pre Amp build/Power Amp mod/Stat speaker project is complete before venturing further afield...

And ...of course...for a ZEN moment...