A couple of interesting and inexpensive i/v valve output stages

[PET-240]

In regards to the Satch dac power supply, have you considered the SALAS shunt reg? There is a guy in germany that has built his own 1541 dac, (  shock another!), have a geezer here, he has some boards for the shunts that have good results apparently...I'm gonna get some for the TeraDAC mario outed sometime back, yes its mine and its getting better.....but I want to move to killer territory without the price tag....

http://www.diyaudio.com/forums/group-buys/167414-reference-tda1541a-dac-i2s-bus-architecture.html#post2202340

Let me know if you want to get some boards, I'll be putting an order in shortly.

[gthicm]

In regards to the Satch dac power supply, have you considered the SALAS shunt reg? There is a guy in germany that has built his own 1541 dac, (  shock another!), have a geezer here, he has some boards for the shunts that have good results apparently...I'm gonna get some for the TeraDAC mario outed sometime back, yes its mine and its getting better.....but I want to move to killer territory without the price tag....

http://www.diyaudio.com/forums/group-buys/167414-reference-tda1541a-dac-i2s-bus-architecture.html#post2202340

Let me know if you want to get some boards, I'll be putting an order in shortly.

These look very good and I have read a lot of people who were very impressed with them.  You could also consider going with simpler shunts using TL431 for example, but technically the Salas shunts are better.  Improving the power supplies to the dac and receiver chip is really worth the effort, assuming the layout of the dac board is good.  This is certainly a weak point in many of the available products.  How does the Killerdac address digital power supply quality? I like his board with the dac decoupling so close to the chip and the small sized caps chosen.  I see also the DEM reclocking, too.  Very nice features.

[ozcal]

In regards to the Satch dac power supply, have you considered the SALAS shunt reg? There is a guy in germany that has built his own 1541 dac, (  shock another!), have a geezer here, he has some boards for the shunts that have good results apparently...I'm gonna get some for the TeraDAC mario outed sometime back, yes its mine and its getting better.....but I want to move to killer territory without the price tag....

http://www.diyaudio.com/forums/group-buys/167414-reference-tda1541a-dac-i2s-bus-architecture.html#post2202340

Let me know if you want to get some boards, I'll be putting an order in shortly.

That would be great Pet . definetly interested.
Thanks ,
G

[ozcal]

I think what this thread shows is that there are many folk who use and love the TDA1541A chip but just like every other area of music reproduction there seems to be hugely varying ideas about how to get the best sound out of the chip.
Vive la difference , I say!

[gthicm]

I think what this thread shows is that there are many folk who use and love the TDA1541A chip but just like every other area of music reproduction there seems to be hugely varying ideas about how to get the best sound out of the chip.
Vive la difference , I say!

Ok, sure.  So what about the digital power supples and layout makes the Killerdac benchmark for some people?  It seems that is is built on a 20 dollar commercially available board from Hong Kong.

[ozcal]

I can't answer that G  as I don't own a KD and have never heard one in my system.
Stevenvalave who designed and builds the KD would be the man to ask.
I think the board used is the one from Analogmetric and that the psu's for the digital board are fairly 'minimalist'.
My next project is to build or have built a psu for the Satch  as described here : http://db.audioasylum.com/mhtml/m.html?forum=tubediy&n=186182&highlight=satch+Thorsten&r=&search_url=%2Fcgi%2Fsearch.mpl%3Fsearchtext%3Dharbeth%2Bc7es%26b%3DAND%26topic%3D%26topics_only%3DN%26author%3D%26date1%3D%26date2%3D%26slowmessage%3D%26sort%3Ddate%26sortOrder%3DDESC%26forum%3Dspeakers by Thorsten.

[gthicm]

I can't answer that G  as I don't own a KD and have never heard one in my system.
Stevenvalave who designed and builds the KD would be the man to ask.
I think the board used is the one from Analogmetric and that the psu's for the digital board are fairly 'minimalist'.
My next project is to build or have built a psu for the Satch  as described here : http://db.audioasylum.com/mhtml/m.html?forum=tubediy&n=186182&highlight=satch+Thorsten&r=&search_url=%2Fcgi%2Fsearch.mpl%3Fsearchtext%3Dharbeth%2Bc7es%26b%3DAND%26topic%3D%26topics_only%3DN%26author%3D%26date1%3D%26date2%3D%26slowmessage%3D%26sort%3Ddate%26sortOrder%3DDESC%26forum%3Dspeakers by Thorsten.

You are definitely headed in the right direction, IMHO.  Rudimentary power supplies work ok, but their is unquestionably significant benefit to optmizing the power supplies to the chip.  It is a testament to the chip's design that you can get pretty good sound from it with fairly basic power supplies.  The TDA1543 was developed I believe as the easier one to implement with fewer power supplies and its output.  I found digital power supplies to make a significant difference when comparing the Satch to the Aya II and some decent Chinese dac kits with shunt regulated power supplies.  The UTS is pretty much ok in stock form.  I would at this point put more effort into the digital side.  I think that you will be very pleased.

[ozcal]

Thanks G . Just for interest sake do you have any liks to the shunt regulated dacs you mention ?

[stevenvalve]

I can't answer that G  as I don't own a KD and have never heard one in my system.
Stevenvalave who designed and builds the KD would be the man to ask.
I think the board used is the one from Analogmetric and that the psu's for the digital board are fairly 'minimalist'.
My next project is to build or have built a psu for the Satch  as described here : http://db.audioasylum.com/mhtml/m.html?forum=tubediy&n=186182&highlight=satch+Thorsten&r=&search_url=%2Fcgi%2Fsearch.mpl%3Fsearchtext%3Dharbeth%2Bc7es%26b%3DAND%26topic%3D%26topics_only%3DN%26author%3D%26date1%3D%26date2%3D%26slowmessage%3D%26sort%3Ddate%26sortOrder%3DDESC%26forum%3Dspeakers by Thorsten.

Right on. I use 3 differant boards. The original ones, I had made with some of my input, Via Melbourne. This board, and the T/L Technical boards. These boards are great, (Analogmetric) if you know how to fully rework Them.

[gthicm]

I can't answer that G  as I don't own a KD and have never heard one in my system.
Stevenvalave who designed and builds the KD would be the man to ask.
I think the board used is the one from Analogmetric and that the psu's for the digital board are fairly 'minimalist'.
My next project is to build or have built a psu for the Satch  as described here : http://db.audioasylum.com/mhtml/m.html?forum=tubediy&n=186182&highlight=satch+Thorsten&r=&search_url=%2Fcgi%2Fsearch.mpl%3Fsearchtext%3Dharbeth%2Bc7es%26b%3DAND%26topic%3D%26topics_only%3DN%26author%3D%26date1%3D%26date2%3D%26slowmessage%3D%26sort%3Ddate%26sortOrder%3DDESC%26forum%3Dspeakers by Thorsten.

Right on. I use 3 differant boards. The original ones, I had made with some of my input, Via Melbourne. This board, and the T/L Technical boards. These boards are great, (Analogmetric) if you know how to fully rework Them.

Ok, so what is the basic design of the digital power supplies?  If it follows these boards, are you just using a three legged regulator followed by filtering and the addition of Solen Fastcaps?  Any further regulation after the first regulators?

[zenelectro]

I can't answer that G  as I don't own a KD and have never heard one in my system.
Stevenvalave who designed and builds the KD would be the man to ask.
I think the board used is the one from Analogmetric and that the psu's for the digital board are fairly 'minimalist'.
My next project is to build or have built a psu for the Satch  as described here : http://db.audioasylum.com/mhtml/m.html?forum=tubediy&n=186182&highlight=satch+Thorsten&r=&search_url=%2Fcgi%2Fsearch.mpl%3Fsearchtext%3Dharbeth%2Bc7es%26b%3DAND%26topic%3D%26topics_only%3DN%26author%3D%26date1%3D%26date2%3D%26slowmessage%3D%26sort%3Ddate%26sortOrder%3DDESC%26forum%3Dspeakers by Thorsten.

Right on. I use 3 differant boards. The original ones, I had made with some of my input, Via Melbourne. This board, and the T/L Technical boards. These boards are great, (Analogmetric) if you know how to fully rework Them.

Ok, so what is the basic design of the digital power supplies?  If it follows these boards, are you just using a three legged regulator followed by filtering and the addition of Solen Fastcaps?  Any further regulation after the first regulators?

WRT the dig side of KD:

You could redesign it with strict EE practices, using multiple bypass ceramic caps + low esr electros, etc and end up with much worse sound.

The chip itself internally is not like modern Cmos IC's and so needs to be treated a little differently. I've been looking at the whole dig/DAC board now for a while
and how to get the absolute most out of it. There can certainly be improvements - or so we might think!

WRT power supplies, every body on this or that forum throws fancy adjectives around to describe the results of their latest power supply
be it shunt regs, ultra low noise super regs, simple series pass regs etc etc. So what -is- the optimum requirement for regs applied to a DAC? Low Z, wide BW, low noise,
shunt operation, series operation? I have a pretty good idea which direction to head based on experience but just following the latest and greatest fad that
is sweeping the net on DAC power supplies is not the answer.

Here's an example, years ago I was involved in designing an amp that was pretty esoteric. It had series pass regs for the front end HT supply. One night I bypassed
the regs altogether and just left raw RC filtering. Result - much better and transparent sound - in that particular application. So much for regulators!

Experience has shown that slow evolution based on careful trial and error with long term listening in a system that is of the highest quality is the way forward.
Experience has also shown that traditional EE solutions don't always translate into better sound. There have been many times when Steven has tried design
changes that I thought were technically not the best approach which translated into better sound.


cheers

T

[gthicm]

I can't answer that G  as I don't own a KD and have never heard one in my system.
Stevenvalave who designed and builds the KD would be the man to ask.
I think the board used is the one from Analogmetric and that the psu's for the digital board are fairly 'minimalist'.
My next project is to build or have built a psu for the Satch  as described here : http://db.audioasylum.com/mhtml/m.html?forum=tubediy&n=186182&highlight=satch+Thorsten&r=&search_url=%2Fcgi%2Fsearch.mpl%3Fsearchtext%3Dharbeth%2Bc7es%26b%3DAND%26topic%3D%26topics_only%3DN%26author%3D%26date1%3D%26date2%3D%26slowmessage%3D%26sort%3Ddate%26sortOrder%3DDESC%26forum%3Dspeakers by Thorsten.

Right on. I use 3 differant boards. The original ones, I had made with some of my input, Via Melbourne. This board, and the T/L Technical boards. These boards are great, (Analogmetric) if you know how to fully rework Them.

Ok, so what is the basic design of the digital power supplies?  If it follows these boards, are you just using a three legged regulator followed by filtering and the addition of Solen Fastcaps?  Any further regulation after the first regulators?

WRT the dig side of KD:

You could redesign it with strict EE practices, using multiple bypass ceramic caps + low esr electros, etc and end up with much worse sound.

The chip itself internally is not like modern Cmos IC's and so needs to be treated a little differently. I've been looking at the whole dig/DAC board now for a while
and how to get the absolute most out of it. There can certainly be improvements - or so we might think!

WRT power supplies, every body on this or that forum throws fancy adjectives around to describe the results of their latest power supply
be it shunt regs, ultra low noise super regs, simple series pass regs etc etc. So what -is- the optimum requirement for regs applied to a DAC? Low Z, wide BW, low noise,
shunt operation, series operation? I have a pretty good idea which direction to head based on experience but just following the latest and greatest fad that
is sweeping the net on DAC power supplies is not the answer.

Here's an example, years ago I was involved in designing an amp that was pretty esoteric. It had series pass regs for the front end HT supply. One night I bypassed
the regs altogether and just left raw RC filtering. Result - much better and transparent sound - in that particular application. So much for regulators!

Experience has shown that slow evolution based on careful trial and error with long term listening in a system that is of the highest quality is the way forward.
Experience has also shown that traditional EE solutions don't always translate into better sound. There have been many times when Steven has tried design
changes that I thought were technically not the best approach which translated into better sound.


cheers

T

Your points are well taken and one can get consumed by chasing the latest and greatest fad or trend and go backwards.  I do not think that there would be any disagreement among most that the venerable TDA1541A chip benefits from better power supplies than the rather simple and antiquated 30 year old designs around when the chip was introduced.  The question I suppose is what are the best imporvements that can be made.

Given that a lot of water has flowed under the bridge since this chip was first produced, there are many people who have spent years trying to optimize the implementation.  These include but are not limited to Thorsten Loesch, Pedja Rogic and the rest of the ususual suspects.  Their work and observations are in the public domain for all to see.  They al stress the importance of optmization of the digital power supplies and they seem to generally advocate the use of tight regulation, often using shunt regulators.  Offhand, I am not aware of anyone now suggesting to go back 30 years with a simple power supply design.  To the contrary.

Again, in a general sense, I agree with your point of view.  However, with respect to the power supplies for the TDA1541A dac, the overwhelming if not unanimous weight of opinion, learned from decades of research and experimentation, is to the contrary.  Also, my limited experience messing about with this chip bears out the observation that these improvements reap worthy benefits.  This is of course not to mention DEM reclocking and i2s attenuation, which are other areas of interest to those seeking to maximize this classic dac chip.

[tuyen]

Anyone tried the tda1541 board from ECDesigns?





(DA1541A-MK4 DAC module. Twin crystal, balanced ultra low jitter masterclock. Ultra high speed synchronous I2S reclockers. Diode-resistor I2S attenuators. Balanced, DC-coupled DEM clock synchronizer. On-board voltage regulators and power supply filters. 12th order LC power supply filter for masterclock and bit reclocker. Passive I/V conversion with dual JFET current buffer and wirewound bias resistor driving a wirewound Mobius Honeycomb passive I/V resistor. Hybrid output coupling caps. Module accepts Philips I2S and can run in both, NOS and OS mode depending on digital audio source specs. The TDA1541A-MK4 is primarily intended for use with the SD-transport as this combination maintains extreme low jitter and interference levels at both, DAC and digital audio source. Output impedance equals 500 Ohms, output amplitude 2Vpp / 0.707V rms. Minimum load resistance equals 10K, wirewound potentiometer is advised in order to maintain lowest possible noise levels. Failing to observe load specifications can lead to severe sound quality degradation. In order to achieve maximum performance, linear power amplifiers with fewest possible semiconductors or tubes in the signal path are recommended. Digital power amplifiers are not recommended for use with the TDA1541A-MK4 module. )

Below is one of my current favorite sounding implementations of the legendary TDA1541 chip that I have been fortunate enough to try on my system (Zanden Model 5000 MK IV)  Not sure what all those magically coils do, but they work very nicely together

[gthicm]

Those appear to be inductors and resistor networks for filtering.  Been there done tthat to and not a bad way to go.  One tube so probably not aon open loop gain stage.  No wonder it sounds good!

Never tried ecdesigns but I have been following the massive thread on another forum.  I think that there is now the Mark 7.  Seems a long maturation process.

[mcb]

I continue to find this thread very interesting.  All my recent reading keeps pointing to the one main theme.  Power supply.  Now all we have to do is figure out what the best option to move forward with is, to lift the Satch a bit.  Gordon has identified the Thorsten L option, however there appears to be a fair few unknowns with this (TL has not kept a record of how he made his changes).  There is also the power supply in the link the PET240 posted, which I assume can also be used.  All I know, is that this is all currently well past my level of understanding.

Keep the ideas flowing.

[gthicm]

I continue to find this thread very interesting.  All my recent reading keeps pointing to the one main theme.  Power supply.  Now all we have to do is figure out what the best option to move forward with is, to lift the Satch a bit.  Gordon has identified the Thorsten L option, however there appears to be a fair few unknowns with this (TL has not kept a record of how he made his changes).  There is also the power supply in the link the PET240 posted, which I assume can also be used.  All I know, is that this is all currently well past my level of understanding.

Keep the ideas flowing.

Just curious, what are the decoupling capacitors for the dac chip?  Wet tantalums? Polycarbonates?  Do you know the values?  Beautiful wood case!

[stevenvalve]

I can't answer that G  as I don't own a KD and have never heard one in my system.
Stevenvalave who designed and builds the KD would be the man to ask.
I think the board used is the one from Analogmetric and that the psu's for the digital board are fairly 'minimalist'.
My next project is to build or have built a psu for the Satch  as described here : http://db.audioasylum.com/mhtml/m.html?forum=tubediy&n=186182&highlight=satch+Thorsten&r=&search_url=%2Fcgi%2Fsearch.mpl%3Fsearchtext%3Dharbeth%2Bc7es%26b%3DAND%26topic%3D%26topics_only%3DN%26author%3D%26date1%3D%26date2%3D%26slowmessage%3D%26sort%3Ddate%26sortOrder%3DDESC%26forum%3Dspeakers by Thorsten.

Right on. I use 3 differant boards. The original ones, I had made with some of my input, Via Melbourne. This board, and the T/L Technical boards. These boards are great, (Analogmetric) if you know how to fully rework Them.

Ok, so what is the basic design of the digital power supplies?  If it follows these boards, are you just using a three legged regulator followed by filtering and the addition of Solen Fastcaps?  Any further regulation after the first regulators?

WRT the dig side of KD:

You could redesign it with strict EE practices, using multiple bypass ceramic caps + low esr electros, etc and end up with much worse sound.

The chip itself internally is not like modern Cmos IC's and so needs to be treated a little differently. I've been looking at the whole dig/DAC board now for a while
and how to get the absolute most out of it. There can certainly be improvements - or so we might think!

WRT power supplies, every body on this or that forum throws fancy adjectives around to describe the results of their latest power supply
be it shunt regs, ultra low noise super regs, simple series pass regs etc etc. So what -is- the optimum requirement for regs applied to a DAC? Low Z, wide BW, low noise,
shunt operation, series operation? I have a pretty good idea which direction to head based on experience but just following the latest and greatest fad that
is sweeping the net on DAC power supplies is not the answer.

Here's an example, years ago I was involved in designing an amp that was pretty esoteric. It had series pass regs for the front end HT supply. One night I bypassed
the regs altogether and just left raw RC filtering. Result - much better and transparent sound - in that particular application. So much for regulators!

Experience has shown that slow evolution based on careful trial and error with long term listening in a system that is of the highest quality is the way forward.
Experience has also shown that traditional EE solutions don't always translate into better sound. There have been many times when Steven has tried design
changes that I thought were technically not the best approach which translated into better sound.


cheers

T

Your points are well taken and one can get consumed by chasing the latest and greatest fad or trend and go backwards.  I do not think that there would be any disagreement among most that the venerable TDA1541A chip benefits from better power supplies than the rather simple and antiquated 30 year old designs around when the chip was introduced.  The question I suppose is what are the best imporvements that can be made.

Given that a lot of water has flowed under the bridge since this chip was first produced, there are many people who have spent years trying to optimize the implementation.  These include but are not limited to Thorsten Loesch, Pedja Rogic and the rest of the ususual suspects.  Their work and observations are in the public domain for all to see.  They al stress the importance of optmization of the digital power supplies and they seem to generally advocate the use of tight regulation, often using shunt regulators.  Offhand, I am not aware of anyone now suggesting to go back 30 years with a simple power supply design.  To the contrary.

Again, in a general sense, I agree with your point of view.  However, with respect to the power supplies for the TDA1541A dac, the overwhelming if not unanimous weight of opinion, learned from decades of research and experimentation, is to the contrary.  Also, my limited experience messing about with this chip bears out the observation that these improvements reap worthy benefits.  This is of course not to mention DEM reclocking and i2s attenuation, which are other areas of interest to those seeking to maximize this classic dac chip.

There is no one thing that makes Killer Dacs sound the way they do. Its a combination of 100+ things that all synergize, an interchange of colouration's, to make music.

[gthicm]

There is no one thing that makes Killer Dacs sound the way they do. Its a combination of 100+ things that all synergize, an interchange of colouration's, to make music

Interesting but not very definitive.  Reminds me of this quote from Blazing Saddles: "My mind is aglow with whirling, transient nodes of thought careening thru a cosmic vapor of invention".  Very funny!

[stevenvalve]

There is no one thing that makes Killer Dacs sound the way they do. Its a combination of 100+ things that all synergize, an interchange of colouration's, to make music

Interesting but not very definitive.  Reminds me of this quote from Blazing Saddles: "My mind is aglow with whirling, transient nodes of thought careening thru a cosmic vapor of invention".  Very funny!

The Killerdac is made very much, so, with out of the box thinking. Do you want a schematic of how it works, and then tell you all the vintage and modern parts to use. and why not tell you the combinations of wire, again vintage and modern, Great Vintage Chokes i use, also the superb old vintage valves i use. There are even ordinary TDA1541A S2 and then great TDA1541A S2, Chips, you need to know the great ones to build a killer. Most are ordinary. I spent 5 years full time on the KillerDaC. Obviously i am not going tell anyone, how i make them. That is why i am vague. Your are an intelligent man, so you will understand.

[stevenvalve]

There is no one thing that makes Killer Dacs sound the way they do. Its a combination of 100+ things that all synergize, an interchange of colouration's, to make music

Interesting but not very definitive.  Reminds me of this quote from Blazing Saddles: "My mind is aglow with whirling, transient nodes of thought careening thru a cosmic vapor of invention".  Very funny!

Its a funny thing but if you built a TDA1541A dac in the way of conventional (technician) thinking, eg, what is on the net, (Ebay and such. boards etc). They will sound quite good. But to be magical you need to radically change there designs and parts choices. They can design stuff, but have no idea how to make them sound magical. They nearly always follow the same (to them) tried and true formula to mediocre.