The KillerDAC Audio forum
KillerDac => General Information => Topic started by: ozmillsy on October 08, 2010, 08:49:27 PM
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Various bits and pieces have been coming together, and the KillerDAC build is about to begin. I thought you all maybe interested in seeing progress photos as it gets built.
The main thing I've been waiting for is my case to arrive. I really like the standard case, but I also like to be a little different (to give it that DIY feel about it 8) ), also I needed something slightly bigger to accomodate the large UTC CG-40 chokes I ordered.
Scouring the web, I found an amp case that looked big enough - and wasnt too costly, although the shipping was more than I'd like. It arrived yesterday, and here are the first photos.
The unpacked case .......
(http://dl.dropbox.com/u/1370915/Audio/Gear/chinese%20case.JPG)
Half assembled.....
(http://dl.dropbox.com/u/1370915/Audio/Gear/chinese%20case_2.JPG)
Choke up close, plenty of room !!
(http://dl.dropbox.com/u/1370915/Audio/Gear/choke_in_case.JPG)
This case is available from here (model A2001B-B, first in the list, [scroll down]):
http://www.vt4c.com/shop/program/main.php?cat_id=1&group_id=2&hit_cat= (http://www.vt4c.com/shop/program/main.php?cat_id=1&group_id=2&hit_cat=)
The branding on the case comes off with alcohol. Shipping was U$88 (by air), more than the cost of the case !! [grumble grumble] but that's ok - worth it to have something slightly different, and big enough for my chokes.
Taking it up to Stevens this weekend, to start the Dac build. Will keep you posted as it progresses.
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Nice Oz. The case looks great should come out very neat. I got a pair of 10Hry UTC chokes as well but christ they are rough compared with yours. Mine are 1750V rated. Wondering how they would physically size up against yours?
(http://i480.photobucket.com/albums/rr165/gamve/KD%20Parts/UTC10HRY200mA1750V.jpg)
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if you ever find yourself selling the chokes I WILL TAKE THEM OF YOUR HANDS :P
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I got a pair of 10Hry UTC chokes as well but christ they are rough compared with yours. Mine are 1750V rated. Wondering how they would physically size up against yours?
My 2 chokes came from different sources, 1 was rougher than the other (this is the good one, the other is already up at Stevens). I hope they both sound the same..... ???
The CG-40's are 90mm wide x 110mm high .
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if you ever find yourself selling the chokes I WILL TAKE THEM OF YOUR HANDS :P
Any law against telling admin to bugger off politely? ;D
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Congrats. Have fun with your build.
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very nice!
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I want my killerDAC case bigger too to fit all the heavyweight parts... Good choice of casing oz, I wonder when flemos starts to take orders....
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I want my killerDAC case bigger too to fit all the heavyweight parts... Good choice of casing oz, I wonder when flemos starts to take orders....
I don't know about you guys but some of the other metal cases look pretty damn good. I must admit I really like the look of the silver anodised aluminium cases assembled with stainless steel hex head bolts. Really sexy IMO, and TBH I think a lot more professional looking than my cases. DIY is awesome, but even better if it looks professional!
Cheers, flemo.
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http://cgi.ebay.com.au/Hi-Fi-DIY-Audio-Power-Amplifer-chassis-case-D998-/290485343950?pt=LH_DefaultDomain_0&hash=item43a24696ce
Something like this would fit the requirements?
Sorry Oz, didn't mean to hijack your thread, more than happy for you to move it if you wish, maybe start a killerchassis thread? 8)
This one though looks killer.......
http://cgi.ebay.com.au/Hi-End-Power-amplifier-Chassis-Case-Full-Aluminum-MK2-/230532633645?pt=LH_DefaultDomain_0&hash=item35acd0d42d
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Sorry Oz, didn't mean to hijack your thread, more than happy for you to move it if you wish, maybe start a killerchassis thread? 8)
No worries, I looked at both of those, before ordering my one. I like 'em both, but the shipping is just nuts. They were both too expensive for me.
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I guess with the MKII weighing 20kg it was never going to be cheap!
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I guess with the MKII weighing 20kg it was never going to be cheap!
20kg air parcel from VT4C (delivered in 6-10 days) costs U$88. I ordered my case with a whole swag of connectors, wire, etc.
But I do like the look of those other ones, if cost is no issue.
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Very nice looking case Oz
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Are you going to post any pic's of the case assembled Oz?
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Are you going to post any pic's of the case assembled Oz?
i got a video of it flemo with oz giving it some tlc
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I shouldve taken a pic the other day. We were playing around with the layout of the components.
Yes, I will, next time I'm at Steven's place.
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Layout finalised.......
(http://dl.dropbox.com/u/1370915/Audio/Gear/MyKiller/DSCN0175.JPG)
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Once the layout was done, we spent some time drilling out holes this arvo.
Some other pics.......
Nextgens in place (top left rca will be the digital input).
(http://dl.dropbox.com/u/1370915/Audio/Gear/MyKiller/DSCN0179.JPG)
Duelands, close enough to be directly connected to the outputs.
(http://dl.dropbox.com/u/1370915/Audio/Gear/MyKiller/DSCN0178.JPG)
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not much to go oz less time on CALL OF DUTY for stevenvalve and it should be ready to plug and tune ;D
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well, I'm sure we'd be further down the road, if a recent visitor didnt pass on the flu ! :o ;D
all good things take time. I was there for about 3 hours yesterday. We made some good progress. The time just flew by, and before I knew it, the missus was on the phone giving me the hurry up.
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very nice oz... i like the idea of the rectifier standing.
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It lives !! :D On my way up for the first listen. It's not in final configuration. Plan is to run it in, then tune.
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YES! Very nice and congrats!
What rectifier is that. Looks like a Type 50 tube!??
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YES! Very nice and congrats!
What rectifier is that. Looks like a Type 50 tube!??
i think its a mesh plate worth about $800 to $1000 type 80 he hardly puts it on its for show he likes looking at it glow
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It lives !! :D On my way up for the first listen. It's not in final configuration. Plan is to run it in, then tune.
Its alive, frankenmillsys DAC lives, breathes, and is playing music. After run in, it is then time for duelunds, new chip TDA1541 S2, rectifier output valves, and redo the wiring, and many more mods.
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The case is big and heavy now that it's loaded. It's a beefy mutha !
(http://dl.dropbox.com/u/1370915/Audio/Gear/MyKiller/DSCN0188.JPG)
(http://dl.dropbox.com/u/1370915/Audio/Gear/MyKiller/DSCN0190.JPG)
It wont normally sit it in that spot, just until the Lightspeed comes back it will be sitting near my ME25.
Those big heat sinks are actually in use. On 1 side we've got 2 resistors up against the heat sink, to dissipate some heat. :)
I dont mind the look of this case from vt4c. 8)
A number of temporary parts in use at the moment (using diff chokes, output caps, etc), mainly waiting for the deulands to arrive before orchestrating the final combination/sound.
Hasnt been switched on (at home), as soon as I walked in the door last night the missus had things for me to do.
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Huh...I see no tubes! :D
Great job oz, would love to hear it if possible.
Cheers,
William
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Huh...I see no tubes! :D
I'd actually like to swap the top with some perspex. That would be cool.
Great job oz, would love to hear it if possible.
Any time you're in the area, you're welcome to pop over for a cuppa.
When it's finalised I'll have a coming out party for this killer. Which reminds me, I've really gotta get my cdp over to DigitalDan, as the system wont be finalised until the transport is in the right condition.
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Thanks for the invite, I won't miss the chance to hear your SGR with the KD! Should be awesome :)
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very nice setup..
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The case is big and heavy now that it's loaded. It's a beefy mutha !
(http://dl.dropbox.com/u/1370915/Audio/Gear/MyKiller/DSCN0188.JPG)
(http://dl.dropbox.com/u/1370915/Audio/Gear/MyKiller/DSCN0190.JPG)
Those big heat sinks are actually in use. On 1 side we've got 2 resistors up against the heat sink, to dissipate some heat. :)
I dont mind the look of this case from vt4c. 8)
Hi Oz, mate I think the kdac looks awesome in that case, and the idea of the acrylic lid is IMO excellent.
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Looks the goods in that case ozmillsy. May it bring you much joy.
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Looks the business oz! Well done my friend!
The power rect tube emits a substantial amount of heat I find. Will this be of a concern with the limited ventilation holes on the lid? I dunno if it is anything to worry about, just was thinking aloud :)
Best
Tuyen
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The power rect tube emits a substantial amount of heat I find. Will this be of a concern with the limited ventilation holes on the lid? I dunno if it is anything to worry about, just was thinking aloud :)
The rectifier is directly underneath the vents on the left side, you can see it glowing through the vents. I think it should be right. I'll keep an eye on it though.
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Fuzzy pic of the rectifier. There is about 1cm gap (maybe slightly less) between the top of *this* rectifier and the lid. I'm hoping the heat from the tube will simply rise straight up through the vents.....
(http://dl.dropbox.com/u/1370915/Audio/Gear/MyKiller/DSCN0193.JPG)
Been on for about 3 hours so far this morning, I just opened the lid and it doesnt seem warm inside.
Sound really effing good !! Cant wait to get the duelands in.
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me and tuyen will visit next year oz it will be tuned by then i hope
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When it's finalised I'll have a coming out party for this killer. Which reminds me, I've really gotta get my cdp over to DigitalDan, as the system wont be finalised until the transport is in the right condition.
Hi ozmillsy,
Count me in the next time you have a few people over. I have been following with interest and would love to hear a KillerDAC. I should organise to have enough time to drop in at Steve's this time.
regards
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Count me in the next time you have a few people over. I have been following with interest and would love to hear a KillerDAC. I should organise to have enough time to drop in at Steve's this time.
No worries Greg.
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Steven came over last night, and we played with caps. The 400V Duelands havent arrived yet, so we're experimenting with some other ones. It has had some auricaps in it, and we changed them with Obligattos. It was a positive change, everything just sound more "together" .
Then we tried some older (2006) AudioNote caps, which I believe are paper in oil. They're heavy buggers. These were in another league, they sounded awesome on this system. They added fluidity and detail at the same time.
The Dac is now running into the battery powered Lightspeed, and the Lightspeed is hooked up to a buffer, to reduce the output impedance. I have to say, matching impedances really makes a big difference to my ears. Adding the buffer into the chain, brings the impedance down that is feeding the amps to 33ohms. The bass has improved out of sight, it's full and solid, and the midbass has weight - that was lost when running without the buffer. Is it the buffer colouring the sound, or is it better impedance matching, that is causing the change? I believe it is more likely the latter, but probably a combination of both. I'm interested to fit a volume pot in the OzKiller, and compare it to the Lightspeed/buffer combo.
An internal VC would be alot simpler, with potentially less compromises? May do that in time, but it's low on the priority list.
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Steven came over last night, and we played with caps. The 400V Duelands havent arrived yet, so we're experimenting with some other ones. It has had some auricaps in it, and we changed them with Obligattos. It was a positive change, everything just sound more "together" .
Then we tried some older (2006) AudioNote caps, which I believe are paper in oil. They're heavy buggers. These were in another league, they sounded awesome on this system. They added fluidity and detail at the same time.
The Dac is now running into the battery powered Lightspeed, and the Lightspeed is hooked up to a buffer, to reduce the output impedance. I have to say, matching impedances really makes a big difference to my ears. Adding the buffer into the chain, brings the impedance down that is feeding the amps to 33ohms. The bass has improved out of sight, it's full and solid, and the midbass has weight - that was lost when running without the buffer. Is it the buffer colouring the sound, or is it better impedance matching, that is causing the change? I believe it is more likely the latter, but probably a combination of both. I'm interested to fit a volume pot in the OzKiller, and compare it to the Lightspeed/buffer combo.
An internal VC would be alot simpler, with potentially less compromises? May do that in time, but it's low on the priority list.
Good work Andrew!
WRT Obbligato's - I had suggested these to SV a few years back as a bargain basement option, it's decent performance for dirt price.
WRT PIO caps, yep it seems the best sounding caps always have something extra besides film/foil. There are a few other options around at
the moment at sub Duelund prices which need to be tried. More on that later.
WRT Buffer, what sort of buffer is it?
WRT Lightspeed high OP impedances & bass, I very much agree with your assumptions.
I also agree, vol control in DAC has many advantages. We have to sort this out. Steven - work to be done !!!!!
WRT KillerDAC MK2 - I've just pumped the height of chassis up to > 100mm (from the old 2 RU) and made more sideways room.
I think the option to use UTC chokes and older caps is worthwhile for those who want to experiment, seeing you guys are having so much fun plugging and playing.
I must be getting soft in my middle age :)
cheers
Terry
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I'm using this buffer.....
http://www.musicalfidelity.com/downloads/archived-manuals/English/x10v3_eng.pdf (http://www.musicalfidelity.com/downloads/archived-manuals/English/x10v3_eng.pdf)
I bought it a coupla years ago, I used it for awhile, then put it aside. Not sure I'd go as far as recommending it, I just happen to have it. It's come in handy on this instance.
An integrated volume control would be better though. 8)
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I'm using this buffer.....
http://www.musicalfidelity.com/downloads/archived-manuals/English/x10v3_eng.pdf (http://www.musicalfidelity.com/downloads/archived-manuals/English/x10v3_eng.pdf)
I bought it a coupla years ago, I used it for awhile, then put it aside. Not sure I'd go as far as recommending it, I just happen to have it. It's come in handy on this instance.
An integrated volume control would be better though. 8)
i used to own one oz a long time ago with the dacv3 and power supply(buffer can be modded)
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I'm using this buffer.....
http://www.musicalfidelity.com/downloads/archived-manuals/English/x10v3_eng.pdf (http://www.musicalfidelity.com/downloads/archived-manuals/English/x10v3_eng.pdf)
I bought it a coupla years ago, I used it for awhile, then put it aside. Not sure I'd go as far as recommending it, I just happen to have it. It's come in handy on this instance.
An integrated volume control would be better though. 8)
Yep, know X10 v3 - I have one in for repair.
Shifting the vol into DAC and loosing the external X10 and Lightspeed will be a good upgrade for the future.
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It seems to be pretty quiet around here lately. All I can say is, I'm time poor at the moment. Once the boy is in bed and asleep, I'm totally wrapped up in the music, which is just sublime....... what a privilege it is to be able to enjoy such a glorious dac, and to think there are still gains to be had - i2s/nos modded transport, dac chip and other upgrades.
We really are far too lucky, fellas.
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It seems to be pretty quiet around here lately. All I can say is, I'm time poor at the moment. Once the boy is in bed and asleep, I'm totally wrapped up in the music, which is just sublime....... what a privilege it is to be able to enjoy such a glorious dac, and to think there are still gains to be had - i2s/nos modded transport, dac chip and other upgrades.
We really are far too lucky, fellas.
thats good oz got my clock going yet?
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thats good oz got my clock going yet?
Nope, that's on hold until the cdp is hotted up, and has the Burson clock fitted. Then I'll compare the M-clock after that.
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Hi,
As a matter of fact I have the Duelunds 0.47/630V at home and going to fit them (in competition with silver foil Audionote) this week as output dac caps.
Are you making any more progress I am very curiuos....your dac looks awesome.
I am going to post a pic of my dac but am searching where in order to stay on topic (extreme modded Dac 3)
Made the cd-transport with an audiofriend as well.
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Hi,
As a matter of fact I have the Duelunds 0.47/630V at home and going to fit them (in competition with silver foil Audionote) this week as output dac caps.
Are you making any more progress I am very curiuos....your dac looks awesome.
I am going to post a pic of my dac but am searching where in order to stay on topic (extreme modded Dac 3)
Made the cd-transport with an audiofriend as well.
please post picture we are very interested
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As a matter of fact I have the Duelunds 0.47/630V at home and going to fit them (in competition with silver foil Audionote) this week as output dac caps.
Are you making any more progress I am very curiuos....your dac looks awesome.
Hi Erik, yes, please do share pics of your dac and transport with us. There is another sub forum called "Other Dacs" if you want to share the story about your Dac.
Let us know how you get on with the output cap shootout. I'm still waiting for the Duelands to arrive, havent done the comparo yet. But the Audionotes are sounding very nice, this dac is running in nicely !
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Yepp, posted a link and a picture in "other dacs".
Today I made a kind of harness for the Duelunds...they are really the size of a hockey puck !!!
I am planning to stack the 2 Duelunds (see pic) in order to be able to implement them in case they top the Audio Note 0.47 Silver Foil/Mylar ;)
For normal size dacs they seem like trouble.......but hey that is what it is all about...our DIY advantage :-X
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2.2uf 400V VSF Copper Foil Duelands installed on the DAC outputs and running in. Chunky buggers, in my chunky Dac case.
Too soon to call, I'm using spare tubes to do the running in, so no critical listening for another 50-100 hours.
(http://dl.dropbox.com/u/1370915/Audio/Gear/DSCN0284.JPG)
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GREAT keep us informed :o ;D
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2.2uf 400V VSF Copper Foil Duelands installed on the DAC outputs and running in. Chunky buggers, in my chunky Dac case.
Too soon to call, I'm using spare tubes to do the running in, so no critical listening for another 50-100 hours.
Super chunky! very cool looking ;)
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I like what I hear so far....... I'm not going to attempt to describe what I'm hearing, because I still have my backup tubes in the dac while running the Duelands in.
But I'm really loath to turn the system off, atm, am enjoying the music immensely.
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Well the 400V Duelands are definite winners on my system. They're excellent, highly recommended.
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Well the 400V Duelands are definite winners on my system. They're excellent, highly recommended.
SAME HERE ....!!!!!
(http://www.htforum.nl/yabbse/index.php?action=dlattach;topic=88295.0;attach=84418;image)
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Been some changes made on the OzKiller in recent times.
Cant remember if I mentioned, but it's now running a Taiwan double crown, which really seems to go well with my system.
Have removed the receiver chip, and am running I2S into it (thanks for the help Crazi). It was seriously like removing a veil from the music, going I2S. There's no going back now.
The rectifier has been swapped out with a u52, what a nice change that was !!
Last weekend Steven came over, and we did some tube rolling of the output tubes (e88's). Tried 3 different sets, and they all changed the sound. 1 set was quite dramatically different, in that they hit a home run. :o Synergy ! ;D
In among all of that, I swapped out my MF tube buffer, with a Burson buffer. The Dac runs into Burson, Burson into Lightspeed. The Burson definetly sounds better on my system that the MF.
I'm a pretty happy chap with the way the system is sounding at the moment. 8)
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I'm a pretty happy chap with the way the system is sounding at the moment. 8)
good news oz
rule number 1 if steve brings tubes over he is not allowed to take them back
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Great stuff oz. Glad to hear you are happy with how your system is sounding :)
The move to I2S is eye opening isn't it. Having the signal bypass the receiver chip, a few caps and resistors and the improvements are quite noticeable! Less is more!! (in this case anyway)
How does the sound differ if you remove the burson buffer and just have the KDAC into the Lightspeed?
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How does the sound differ if you remove the burson buffer and just have the KDAC into the Lightspeed?
The music loses "weight", it's thin. Bass becomes abit loose to my ears. Bass is tight and fast with the burson buffer in the loop.
The Lightspeed is not a good match for the Killer without a buffer in between, IMHO - even George discourages it, on the basis of a poor impedance match. But with the buffer in the loop, it's great. The Burson+Lightspeed option is working really well for me.
The Burson appears cleaner than the MF to me. The MF buffer has a "sound" that works in some cases - eg: I've used it behind the preouts of my receiver, and it improved things dramatically. But for my 2ch music requirements, I feel it had a veiled effect.
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More changes have been made to the OzKiller.
We (the lone ranger and tonto, see below footnote at the bottom to explain this reference):
* re-arranged the Duelands and R/L outputs, and tidyed up the wiring runs to the Duelands in the process.
* added permanent I2S input rca sockets (which went nicely on the back of this amp case which had free socket holes available).
This was in preparation for the return of my hot-rodded CD94 from Danny Digital (the current cd94 in use, has been on loan, thanks Steven).
My CD94 is different to the one I've had on loan. I didnt want exposed wires running between transport and dac (I have kids that like to play with things). So DD put I2S rca outputs on the rear of the CD94. He also added an internal buffer to drive the I2S outputs, this ensures a strong 5v signal that is capable of being run out the rcas, down short coaxial digital cables, and into sockets at the dac end. This wouldnt be advisable without the buffer, as the i2s outputs that are tapped into on the player arent designed to drive anything but a very short point to point run.
So now I have a nice tidy cable run of 3 x short digital coaxial cables between cd94 and dac. Dac is now all closed up and safe from prying hands or bouncing balls.
DD also added my Burson clock, and included a external dc power plug on the case, so I could power my clock with my external battery. Very neat, no open wires running to external batteries. CD94 completely sealed, and again, closed up from prying hands and bouncing balls.
DD did some other mods, he disconnected the analog section, and also did a power mod for the digital boards (which is supposed to clean up the power that is feeding those digital boards) - and some other bits and pieces.
Hooked up my CD94 (to the freshly modded Killerdac) tonight, everything works as it should.
Havent listened at reference levels yet, I'm drawing no conclusions about whether there are any losses to this approach (versus the straight wire I2S option). At this stage, I'm just happy I dont have to worry about the kids tugging on open air wires.
Will take some photos later. It's getting abit late in the day.
[footnote: re LR/tonto reference, everytime I mentioned to SV that "we" can make a change here, and a change there - he puts on his best Tonto voice and says; what do you mean "we" paleface?!? bahaha
Thanks again for your help Tonto, and thanks to DD for his excellent work on the CD94.
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now your talking business oz very interested to this approach seems very child friendly and a huge waf which is what my system is lacking big time
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Havent listened at reference levels yet, I'm drawing no conclusions about whether there are any losses to this approach (versus the straight wire I2S option).
Looking forward to the comparison Oz, mine used the same digital RCA connections as yours but I can't do comparison because this is the only CD94 I have.
A little advice for all CD94 users, never let the CD94 unused for a prolonged period of time, I left mine for about 4 months unused when I was away and because of this the rubber belts started to slip due to developing shape memory, I can't load CD automatically anymore because the tray keep ejecting, so now in order to load the CD I have to push gently the big white roller close the transformer (see pic).
DD says all I can try to do is to re-lube all the friction points and try another belt, I haven't got time to do it but I really hope my CD94 can operate normally again after the treatments.
Cheers,
William
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Havent listened at reference levels yet, I'm drawing no conclusions about whether there are any losses to this approach (versus the straight wire I2S option).
Looking forward to the comparison Oz, mine used the same digital RCA connections as yours but I can't do comparison because this is the only CD94 I have.
A little advice for all CD94 users, never let the CD94 unused for a prolonged period of time, I left mine for about 4 months unused when I was away and because of this the rubber belts started to slip due to developing shape memory, I can't load CD automatically anymore because the tray keep ejecting, so now in order to load the CD I have to push gently the big white roller close the transformer (see pic).
DD says all I can try to do is to re-lube all the friction points and try another belt, I haven't got time to do it but I really hope my CD94 can operate normally again after the treatments.
Cheers,
William
William,
I understand your experience with this. I got a set of belts on Ebay from the USA which were supposed to a 'genuine quality' item. I had many months of trying to sort out what I thought was a slightly sticky drawer mechanism etc. I spoke with one of my Marantz wholesalers and they went 'Sure we have those belts' so I got a set... and guess what... all the problems disappeared. Works like a charm now with nice solid Marantz Tank-like action. Amazing what the correct item will do. Drop me a PM if you would like to try a set.
Cheers
Rawl
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* added permanent I2S input rca sockets (which went nicely on the back of this amp case which had free socket holes available).
I didnt want exposed wires running between transport and dac (I have kids that like to play with things). So DD put I2S rca outputs on the rear of the CD94. He also added an internal buffer to drive the I2S outputs, this ensures a strong 5v signal that is capable of being run out the rcas, down short coaxial digital cables, and into sockets at the dac end.
DD also added my Burson clock, and included a external dc power plug on the case, so I could power my clock with my external battery. Very neat, no open wires running to external batteries. CD94 completely sealed
At this stage, I'm just happy I dont have to worry about the kids tugging on open air wires.
Hi Oz,
I did the same with my CD85 with the power supply to the clock. I inserted a DC plug straight in where the original power cord fitted which became a useless hole after I installed the IEC socket. My CD85 is also completely self contained and just plug and play. Oh how I hate loose Cat5 cable sticking out everywhere!!!
I too was thinking of adding some sort of plugs for the I2S but wasn't sure how to overcome the longer leads issue, which DD has. My CD85 has the I2S leads all ready to go which was done by DD when he modded the PCB and removed the S1 chip. My system had been pretty much been sitting all year due to lack of interest really.
I have a CD94 mkII sitting there and was going to sell it but if I can muster up some enthusiasm I may ship it to DD for a complete transport modification like you have done. My CD85 is pretty damn good though which is why I haven't really had any interest in modding the CD94 mkII.
I'll look forward to seeing the pic's!
Cheers, flemo.
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Pics ......
CD94/Ozkiller (clock battery pack sitting on top left side of cd94)
(http://dl.dropbox.com/u/1370915/Audio/Gear/cd94_kdac.jpg)
CD94 outputs (battery pack fuzzed out in the foreground, sorbothane dome under 1 foot (these things really work))
(http://dl.dropbox.com/u/1370915/Audio/Gear/cd94_outputs.JPG)
CD94 internals (pink circle is the i2s output buffer)
(http://dl.dropbox.com/u/1370915/Audio/Gear/cd94_internal_mods.jpg)
ozkiller inputs (temporary cables in use)
(http://dl.dropbox.com/u/1370915/Audio/Gear/kdac_rear.JPG)
ozkiller internal view (alot tidyer now than it was, duelands close to & directly connected to the output sockets).
(http://dl.dropbox.com/u/1370915/Audio/Gear/kdac_i2s_internals.JPG)
closer view of the dac board
(http://dl.dropbox.com/u/1370915/Audio/Gear/kdac_board.JPG)
i2s pinout instructions for the receiver chip socket on the dac board (got this from crazi)
(http://dl.dropbox.com/u/1370915/Audio/Gear/i2s.JPG)
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Very nice work Oz by the "team".
Your kdac has been very well constructed and finished. It looks like a commercially made product and I mean that in the highest regard. That's how I'd like mine finished, including the cabinet. Once i get mine finished I'll probably buy a cabinet like yours and have a technician go through the whole thing to get that same quality internal finish as well. I believe if sounds like a Killer then it should look like a Killer too!!
I'll have to post some updated pic's of my CD85, but apart from the I2S connections, and mine has the Kajak12 clock and massive vintage cap on the back, they are similar. Of course DD had done an outstanding job on your CD94 including the mounting of the clock, which is something I need to improve on my CD85.
Is your clock standard or have the caps been upgraded/changed? I didn't see anything which looked oil filled or vintage?? :o
Cheers, flemo.
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Your kdac has been very well constructed and finished. It looks like a commercially made product and I mean that in the highest regard. That's how I'd like mine finished, including the cabinet. Once i get mine finished I'll probably buy a cabinet like yours and have a technician go through the whole thing to get that same quality internal finish as well. I believe if sounds like a Killer then it should look like a Killer too!!
Given the choice, I'd go for a Killerflemo case. :D But I'm pretty happy with this one. If I did it over again, I'd have mounted the SPDIF input in the 4th spare hole on the back. When we initially did it, a Dueland was in the way, which is why the spdif is now mounted near the left output rca socket.
Is your clock standard or have the caps been upgraded/changed? I didn't see anything which looked oil filled or vintage?? :o
The clock is the next thing to do. I'm running a stock standard Burson clock. I'll be trying a Mariospecial at some stage. Also looking forward to trying Zen's clock that is in development.
On this player, I also havent changed the power socket over to an IEC. It's still standard. I did the IEC mod on my 960.
So, there are still things to do on the transport, to try and squeeze some more performance out of it. It's pretty good now though.
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The Lightspeed is not a good match for the Killer without a buffer in between, IMHO - even George discourages it, on the basis of a poor impedance match. But with the buffer in the loop, it's great. The Burson+Lightspeed option is working really well for me. The Burson appears cleaner than the MF to me. The MF buffer has a "sound" that works in some cases - eg: I've used it behind the preouts of my receiver, and it improved things dramatically. But for my 2ch music requirements, I feel it had a veiled effect.
Gamve is very enthusiastic about the Truth pre-amp. He thinks it bests a Burson and Lightspeed. He was so enthusiastic about it I got one and its now on its way out here. John Darko is going to review it but not for a while - he is evidently waiting on the NAKSA 100. If you are amenable happy to send it down to check out prior to going to John.
Thanks
Bill
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If you are amenable happy to send it down to check out prior to going to John.
Sure, that would be great. Cheers
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Oz, Thats looking really neat, nice work. How much did the Lone Ranger help? Ha Ha.
Thanks for posting the I2S instructions will be following suit once my unit is a bit more run in.
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Oz, Thats looking really neat, nice work. How much did the Lone Ranger help? Ha Ha.
The Lone Ranger kept coming up with bright ideas, and Tonto was bemused saying "you dont realise how much work this is !!" . What was intended to be a 2 hour visit, turned into 6+ hours. Time flies. Tonto was very patient, and I'm very grateful. :)
Thanks for posting the I2S instructions will be following suit once my unit is a bit more run in.
No worries.
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Oz, Thats looking really neat, nice work. How much did the Lone Ranger help? Ha Ha.
The Lone Ranger kept coming up with bright ideas, and Tonto was bemused saying "you dont realise how much work this is !!" . What was intended to be a 2 hour visit, turned into 6+ hours. Time flies. Tonto was very patient, and I'm very grateful. :)
Thanks for posting the I2S instructions will be following suit once my unit is a bit more run in.
No worries.
What is this, we, white man
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...He also added an internal buffer to drive the I2S outputs, this ensures a strong 5v signal that is capable of being run out the rcas, down short coaxial digital cables, and into sockets at the dac end. This wouldnt be advisable without the buffer, as the i2s outputs that are tapped into on the player arent designed to drive anything but a very short point to point run.
Hi Oz,
Looks good. I'm planning on tapping in to the I2S from by Marantz CD63Mk2. Could you let me know the following:
What buffer did you use?
Where did you supply the 5V supply and ground to the buffer from?
Is the ground for the I2S signal available from the ground connections on the RCA?
Thanks,
Simon
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Hi Simon,
Dannydigital did all the mods, I couldnt answer your questions I'm afraid.
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This week my custom made digital coaxial cables arrived. 55cm in length, which turned out to be just right (it was close).
I've dabbled with cable making, as per my other cable threads. But with the arrival of our second, I just dont have the time available to experiment with cable making. I found a SNA forum member by the name of Little Blue Penguin who makes very high quality cables at a reasonable price. All my cables on the Killerdac are made by LBP, the power cable, the rca interconnects, and now the digital cables.
It was pretty good before, but after switching over the digital cables, I reckon it is sounding just sublime.
Some eye candy.....
(http://dl.dropbox.com/u/1370915/Audio/Interconnects/lbp_i2s0.jpg)
(http://dl.dropbox.com/u/1370915/Audio/Interconnects/lbp_i2s1.jpg)
(http://dl.dropbox.com/u/1370915/Audio/Interconnects/lbp_i2s2.jpg)
Highly recommended cables. If you're like me and cant be bothered making your own, and you'd like to give these a try, you can contact Little Blue Penguin via PM on SNA. I started a thread over there on his cables, here....
http://www.stereo.net.au/forums/showthread.php/34700-Little-Blue-Penguin-Custom-Cables (http://www.stereo.net.au/forums/showthread.php/34700-Little-Blue-Penguin-Custom-Cables)
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I should also add, that I havent compared the new CD94 with buffered 5v i2s outputs, to the loaner from SV with direct wire I2S.
I'm not going to. :o The new transport sounds soooo good, I dont want to know if there is a difference. :o Sounds funny I know, but ignorance is bliss. I simply cant have a direct exposed wire setup, and therefore I dont want to lust after it. :-\
Apologies if anyone wanted to know the difference. From my ignorant position, I believe the 2 solutions are as good as each other. ;D
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This week my custom made digital coaxial cables arrived. 55cm in length, which turned out to be just right (it was close).
I've dabbled with cable making, as per my other cable threads. But with the arrival of our second, I just dont have the time available to experiment with cable making. I found a SNA forum member by the name of Little Blue Penguin who makes very high quality cables at a reasonable price. All my cables on the Killerdac are made by LBP, the power cable, the rca interconnects, and now the digital cables.
It was pretty good before, but after switching over the digital cables, I reckon it is sounding just sublime.
Some eye candy.....
(http://dl.dropbox.com/u/1370915/Audio/Interconnects/lbp_i2s0.jpg)
(http://dl.dropbox.com/u/1370915/Audio/Interconnects/lbp_i2s1.jpg)
(http://dl.dropbox.com/u/1370915/Audio/Interconnects/lbp_i2s2.jpg)
Highly recommended cables. If you're like me and cant be bothered making your own, and you'd like to give these a try, you can contact Little Blue Penguin via PM on SNA. I started a thread over there on his cables, here....
http://www.stereo.net.au/forums/showthread.php/34700-Little-Blue-Penguin-Custom-Cables (http://www.stereo.net.au/forums/showthread.php/34700-Little-Blue-Penguin-Custom-Cables)
Hi ozmillsy,
I really like the look of your new cables, they look very solid. I use 50 cm generic RCA cables and it's hideous! Thanks for the seller info, I might order some in the future when I get my other priorities sorted first.
The I2S comparo is a big dilemma, isn't it? I can't stand exposed wires as well...unless they all look like Nordost Odin ;D or when I have my own shed 8)
Cheers,
William
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I should also add, that I havent compared the new CD94 with buffered 5v i2s outputs, to the loaner from SV with direct wire I2S.
I'm not going to. :o The new transport sounds soooo good, I dont want to know if there is a difference. :o Sounds funny I know, but ignorance is bliss. I simply cant have a direct exposed wire setup, and therefore I dont want to lust after it. :-\
Apologies if anyone wanted to know the difference. From my ignorant position, I believe the 2 solutions are as good as each other. ;D
Oz i admire your control in not changing back to the other transport i could not do it
looks professional oz just like a shop bought product
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Very neat Oz.
Will check out the penguin, looks like good quality at a reasonable price. Would like
to do much the same as you when I go to I2S.
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Hey Guys, well the time has come to take a closer look at re-tuning the Dac for my current system.
My system has been sounding rolled off, and I have been tackling that gradually. The biggest culprit has been the Radford amp, which was a self-imposed problem that has been fixed. I also changed my volume control to a passive, and this has given me a clearer window to the sound.
The VC->AMP->SPEAKER combination is now really humming for my R2R and Vinyl rigs. I am getting amazing extension at the top end now, nice silky extension (not harsh). It took a bit of IC fiddling to get it just right, but it's almost there.
What all this has revealed is, the DAC (in comparison to my other front end components) has been rolled off all along, and has been contributing to the problem !! Like a lot of things in audio, it's never 1 thing, it's a combination of things.
So I will start making updates in this thread on the things I am changing, to attempt to tune in the DAC, and get better top end extension.
1st change I have made is the Chokes. I'll post pics of what has been changed shortly.
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Post on the choke changes and what happened. I previously had these chokes in the DAC,,,,,,,
(http://dl.dropboxusercontent.com/u/1370915/Audio/Gear/MyKiller/20140716_085729.jpg)
I dont know what they are, but they are really heavy like an Oil filled choke. And they have a similar kind of character. They give a beautiful liquidity and wetness to the sound. Like a Freed choke does, but not to the same extreme. When we were first dialling in the DAC, it was to drive my SS amps in the SGR speakers, and these chokes gave that system what it needed (SS amps can tend to be a little dry).
But this lovely liquidity and wetness comes at an expense, these chokes lack some top end clarity. This has become very obvious on the current Tannoy/Radford system. They are coming out of the DAC, but I am keeping them because in a different component, in a different part of the system, they could be magical. We need different sounding parts like this to dial things in.
I've changed the above chokes with some newer UTC chokes. There are a number of different UTC models. The ones I am using, are (I believe) to be the preferred choice for current model Killerdacs? Model H-72. Here are the pics.
(http://dl.dropboxusercontent.com/u/1370915/Audio/Gear/MyKiller/20140716_085212.jpg)
(http://dl.dropboxusercontent.com/u/1370915/Audio/Gear/MyKiller/20140716_085104.jpg)
These H-72 chokes are very nice sounding chokes. They have top end transparency, and simply a nice balanced natural sound.
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Nice one Oz, can't wait to hear it mate
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Post on the choke changes and what happened. I previously had these chokes in the DAC,,,,,,,
(http://dl.dropboxusercontent.com/u/1370915/Audio/Gear/MyKiller/20140716_085729.jpg)
I dont know what they are, but they are really heavy like an Oil filled choke. And they have a similar kind of character. They give a beautiful liquidity and wetness to the sound. Like a Freed choke does, but not to the same extreme. When we were first dialling in the DAC, it was to drive my SS amps in the SGR speakers, and these chokes gave that system what it needed (SS amps can tend to be a little dry).
But this lovely liquidity and wetness comes at an expense, these chokes lack some top end clarity. This has become very obvious on the current Tannoy/Radford system. They are coming out of the DAC, but I am keeping them because in a different component, in a different part of the system, they could be magical. We need different sounding parts like this to dial things in.
I've changed the above chokes with some newer UTC chokes. There are a number of different UTC models. The ones I am using, are (I believe) to be the preferred choice for current model Killerdacs? Model H-72. Here are the pics.
(http://dl.dropboxusercontent.com/u/1370915/Audio/Gear/MyKiller/20140716_085212.jpg)
(http://dl.dropboxusercontent.com/u/1370915/Audio/Gear/MyKiller/20140716_085104.jpg)
These H-72 chokes are very nice sounding chokes. They have top end transparency, and simply a nice balanced natural sound.
and at 70ma the choke will be more suitably loaded to work in it's correct operating range?
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and at 70ma the choke will be more suitably loaded to work in it's correct operating range?
70 or 125?
What determines the # of HY's (the inductance)?
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70ma. I think 125ma is getting into low power, power amplifier territory.
You could try it both ways and see what sounds best but the choke would be loaded beter at 70ma.
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70 or 125?
What determines the # of HY's (the inductance)?
The UTC's have a good current versus inductance rating, ie; at 70mA you get 13 Henrys, at 125mA you get 7 Henrys.
At 15mA or so of KD there may be even more, say 15 to 20 Henrys.
The more Henrys, the better filtering. At 20 Henrys you may be even able to use a smaller cap on the OP tube
and ditch the Jensen for a film / oil filled cap. Jensen electros are pretty coloured and fat sounding IMO. They are not always
the right solution in all cases.
cheers
Z
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Zen, great to see you back posting. :D. I was hoping you'd see my post and explain how the choke is working. Thanks.
Looking at the original chokes I pulled out, they don't appear to be dramatically different. 150ma I get 8 Hy's. I assume as the current drops, the Hy's increases on these chokes aswell? We just don't have a number printed on the choke to guide us? Is that right?
When you say smaller value cap, what are you measuring to determine the right value? This gets into circuit design I guess, which could get complex, but doesn't stop me asking. :)
I vaguely remember the Jensons used in the Killer to be 100uf (I'll check this). For example, if I dropped the cap value to 50uf, what is the effect on the OP tubes?
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The UTC's have a good current versus inductance rating, ie; at 70mA you get 13 Henrys, at 125mA you get 7 Henrys.
At 15mA or so of KD there may be even more, say 15 to 20 Henrys.
The more Henrys, the better filtering. At 20 Henrys you may be even able to use a smaller cap on the OP tube
and ditch the Jensen for a film / oil filled cap. Jensen electros are pretty coloured and fat sounding IMO. They are not always
the right solution in all cases.
cheers
Z
GREAT to see you back on the net...this post has made my day...
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Next tuning tweak, resistors.
There are currently 70R Allen Bradleys next to the OP tubes. Here,,,,,,,
(http://dl.dropboxusercontent.com/u/1370915/Audio/Gear/MyKiller/20140719_102654.jpg)
In this particular spot, I am advised that the resistors can be between 0-100 , or 40-80 (being more conservative).
Aside from a change in volume, I'm told the lower the resistor value, the cleaner the sound. The higher the value, the weightier it gets.
Looking through my collection of 2w Shinkohs, I have 47R and 75R values. I'll begin with changing out the 70R-AB's with 47R-Shinkohs. This should be quite a change. AB's have an inherent richness to them, changing to Shinkoh and coupled with the change in resistor value, should be quite interesting.
Side by side.
(http://dl.dropboxusercontent.com/u/1370915/Audio/Gear/MyKiller/20140719_103640.jpg)
Shinkohs installed.
(http://dl.dropboxusercontent.com/u/1370915/Audio/Gear/MyKiller/20140719_104327.jpg)
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Obviously 1 of the easiest Killerdac mods is tube rolling. This post will be about output tubes, there is no shortage of options.
The recommended choice of tube type for the KD outputs has been Phillips Miniwatt SQ E88CC tubes. But oils aint oils, and there are any number of variants of this type of tube.
I have 4 types on hand, and they all sound different. I'll list them here, with comments on how they sound (baring in mind everything is system dependent).
First type is the one I have been using for the last couple of years, and what most people would have heard (for those who have previously visited me).
SQ's with writing on top
(http://dl.dropboxusercontent.com/u/1370915/Audio/Gear/MyKiller/SQ-Writing.jpg)
This tube is very nice, it has body and a good amount of detail/sound staging. It's a bit of an all rounder.
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SQ's with writing and stars
(http://dl.dropboxusercontent.com/u/1370915/Audio/Gear/MyKiller/SQ-Stars.jpg)
This tube is highly sought after, but it isnt necessarily the best. What people love about this tube, is that it adds a sense of real flesh and weight to voices. Most audio systems are lean and analytical, and these tubes are a quick fix for that. But that flesh on the bone comes at a price, you lose speed and detail. The bottom end is quite soft, I wont say woolly thats going too far, but it isnt tight.
For those people that love the J.Cash style vocal music, with real weight in delivery, you'd love these tubes.
This tube has an O getter (most of the SQ's do).
(http://dl.dropboxusercontent.com/u/1370915/Audio/Gear/MyKiller/SQ-Stars_Ogetter.jpg)
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SQ's with Stars, D getter
(http://dl.dropboxusercontent.com/u/1370915/Audio/Gear/MyKiller/D-Getters.jpg)
These tubes are quite scarce. They have the stars on them, but no writing on top, and they have a different getter (see here,,,,).
(http://dl.dropboxusercontent.com/u/1370915/Audio/Gear/MyKiller/D-Getters_D.jpg)
These tubes sound quite special. They are not slow like the other stars, they have good weight, good detail, their strength is a harmonic beauty in delivery. Like we get some additional decay, and this makes everything sound that much more engaging.
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SQ's-Plain
(http://dl.dropboxusercontent.com/u/1370915/Audio/Gear/MyKiller/SQ-plain.jpg)
No stars, no writing on top, standard O getter.
My current favourite tube. It has strong-really tight bass, big sound staging and tight imaging, clean sounding, with a hint of decay and beauty (not the same degree of decay as the D getter, but it has just enough to stop this tube from sounding analytical).
This tube really suits my current system. I already have an inherently warm and engaging sound with Tannoy Golds and Radford amp, these tubes tighten up the sound, and let through more detail. They may not be for all systems, but they are hitting the mark on mine.
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To complicate matters further, there are date codes on the tubes, and you know it, the different dates sound different.
I heard a pair of early 60's SQ-Plain type tubes, and they left me a little cold. IIRC, the plain SQ's above are from '59.
The other tubes I have posted about are all from the 50's. I think production quality improved in the 60's, resulting in less distortion, but this doesnt mean they sound better. I guess it all depends on your system.
It's handy to have different tubes in your collection. I have used all of these tubes, at different times, on different system configurations and in different rooms.
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Nice collection of E88CC there Oz.
You might want to speak to Bryan as I remember he uses different output valves for his KillerDAC. Not sure what valves but who knows, you might end up liking the sound :)
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Definitely open to trying the same tubes Bryan runs.
Those plain '59 SQs are sounding sweet in the meantime though.
Also have a couple more tweaks to try, in due course.
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Next mod, in the search for some more top end clarity, swap out the Dublier 8uf cap with a Plessey.
The Plessey is reported to be clean and clear with more extension, the Dublier is fuller and weightier but has a tendency to be thick on the wrong system.
(http://dl.dropboxusercontent.com/u/1370915/Audio/Gear/MyKiller/20140726_093853.jpg)
Plessey installed,,,,
(http://dl.dropboxusercontent.com/u/1370915/Audio/Gear/MyKiller/20140726_101556.jpg)
(thanks for the tip Jehuty)
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Next mod, in the search for some more top end clarity, swap out the Dublier 8uf cap with a Plessey.
The Plessey is reported to be clean and clear with more extension, the Dublier is fuller and weightier but has a tendency to be thick on the wrong system.
(http://dl.dropboxusercontent.com/u/1370915/Audio/Gear/MyKiller/20140726_093853.jpg)
Plessey installed,,,,
(http://dl.dropboxusercontent.com/u/1370915/Audio/Gear/MyKiller/20140726_101556.jpg)
(thanks for the tip Jehuty)
Hi Oz, do you like the Plessey better than the Dubilier?
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Hi Oz, do you like the Plessey better than the Dubilier?
Listened for about an hour, and sounds promising. The Plessey is brand spanking new, and will likely benefit from some running in.
But I am definitely edging closer to my reference (the r2r).
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Good news Oz. Now, you only need a Studer chip I reckon :D
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I would like a Studer r2r. Thats what I really need. Tape is where it's really at. 8)
A studer chip would be nice, but not essential anymore, following recent changes.
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Nice collection of E88CC there Oz.
You might want to speak to Bryan as I remember he uses different output valves for his KillerDAC. Not sure what valves but who knows, you might end up liking the sound :)
AFAIK Brian is using 6C45 Pi Russian super tubes on his DAC.
These are somewhat like the venerable WE437A. They are pretty tricky to implement and love to oscillate.
They have higher OP and more drive than ECC88 etc but if you have Russian tube phobia then best avoid.
I have not compared them back to back against ECC88 as they are different pinout and run very different currents etc.
Z
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Hey Z, if i was to try them, do I need to change other stuff around the tube?
Things are starting to come together now, without going for that option.
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Hey Z, if i was to try them, do I need to change other stuff around the tube?
Things are starting to come together now, without going for that option.
Yes mate, you need to re wire the socket, and run a bit more current through the tube.
I think they also run better choke loaded, (instead of a plate resistor) but haven't tried it.
There are quite a few mods that might get you some more top end clarity.
What I-V resistor are you using?
What regs are you running on your KD?
What bit bypass caps (14x) are you running?
Lot's of options.
cheers
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Hey mate,
I've come a long way, with the mods I have documented in this thread thus far.
I am getting to the point where I run the risk of going too far. I have a bit more reference comparisons to do (with the r2r), to be sure.
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the DAC (in comparison to my other front end components) has been rolled off all along.
Hi Andrew, i have only just caught up with this thread.
Just FYI, below are some frequency response measurements i did, comparing my killerdac with an Auralic Vega DAC. I won't have to tell you which curve is which! The rolloff seems consistent with the classic NOS "droop". I wonder whether that is what you are hearing, or whether there is some other factor...?
Anyway, it seems to me that one possible way to address that is to -- shock, horror -- apply a compensating filter to our digital files so that they are effectively flat when played back on a NOS dac like the killerdac. Since we often burn our own CDs, that should not be difficult... or even those of us dabbling with .. gulp ... computer transports.
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Hey rab, that is an impressively flat graph (roll off aside). Some people have commented that the Killerdac seems to have a midrange push, but this is not what your graph shows.
Yes, the natural rolloff of the tda chip (in NOS mode) could definitely be part of it, no doubt. But also, my dac had a bunch of parts in it that were rich and almost bordering on thick, and this was robbing it of some top end extension (there are always trade offs).
I'm happy with where it is at now, and am nearly ready to demo it at the next GTG I organise. My tannoy system has always been a bit thick in delivery, and I had incorrectly assumed it was the tannoys. The penny dropped when I was doing some vinyl to digital comparisons (digital recordings of my vinyl rig used for the comparo), then I did some R2R comparisons (using same method, digital recordings taken from tape). The dac was the problem.
But the changes I have made, are worth trying (1 at a time), it sounds soooo much more extended now.
In summary,
* chokes (massive change)
* resistors (allen bradley changed to 2w shinkoh)
* output tubes (changed miniwatt SQ tubes)
* cap (dubilier to plessey)
I have also changed my rectifier to a brown base KBZ type, which I havent documented here yet.
More possible changes are, chip rolling and there is another set of AB resistors (100k) on the output sockets. But I dont think I need to go there.
When you are next in sydney, come visit me rab, the system is radically different to when you last heard it (in a different house and room, with any number of other changes).
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Great stuff Andrew. I dip into this stuff from time to time as I want to improve the sound of my Tram2 preamp and Modjeski DD amp. Always chasing more body (Steve's 'flesh and bone'), changing caps, resistors, etc.
Thanks also for the invitation to visit: i am long overdue for a visit to the Blue Mountains and would love to hear what you have done. However, i am preparing for a big OS trip in September so it will be a while... maybe next year.
- r.
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Hey rab, that is an impressively flat graph (roll off aside). Some people have commented that the Killerdac seems to have a midrange push, but this is not what your graph shows.
Yes, the natural rolloff of the tda chip could definitely be part of it, no doubt.
There's no roll off of the TDA chip. All 0 x oversampling DAC's (at 44.1KHz) will have this roll off due to the absence of digital filter.
It's about -2.5 to 3dB at 20kHz and it's the sinx/x response.
I would also expect any other 0 x OS DAC to be flat in pass band unless they are broken. Any midrange warmth or boost is just added
harmonics / distortion.
cheers
Terry
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Yes, I should have stated TDA in nos mode. Have fixed that. Cheers
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:) Just want to mention that IMV having a flat FR measurement on front end eqp bears very little effect in the big picture for the total room response which is what we hear. Try measuring any speakers 3 or so meters away in the listening seat for a real shock. Peaks and troughs introduced by the room and speaker combination will totally dominate any FR measurements.
What Oz has experienced by changing out components for the same or similar value devices is differences to tonality and hf extension. Great write up by the way on the effects of changing various components. Keep it coming.
V
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:) Just want to mention that IMV having a flat FR measurement on front end eqp bears very little effect in the big picture for the total room response which is what we hear. Try measuring any speakers 3 or so meters away in the listening seat for a real shock. Peaks and troughs introduced by the room and speaker combination will totally dominate any FR measurements.
I've done that (measuring HF at seating position), and totally agree. It's why people measure HF near field. Am using my ears in this room, I'm not trying to measure 'flat'. I am shooting for similar HF extension that I am getting from my R2R, same room, same recordings (xfer'd), different front end.
What Oz has experienced by changing out components for the same or similar value devices is differences to tonality and hf extension. Great write up by the way on the effects of changing various components. Keep it coming.
Changing the parts I have done so far in the dac is having quite a dramatic effect. I'm really happy with where it is sitting, but there is a smidge more to wrestle out of the system.
Tried some KLEI IC's between dac and VC last week, and what I got was a dramatic change in transparency, night and day stuff. Can hear the difference in the other room. ;) But, with these IC's, sibilance was more pronounced. So,,,,, does that mean retain the IC's and dial back some changes in the DAC, or stick with my darker IC's? Also have the treble settings on the Golds, that are in the mix. Fun, fun. :-\
I feel like the KLEI's are letting more through, and therefore I could have gone a smidge too far with the dac. It's getting to the pointy end of dialling in the dac (on this system/room) now ,,,,,,,,,, and then I'll move house again. ???
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Tried some KLEI IC's between dac and VC last week, and what I got was a dramatic change in transparency, night and day stuff. Can hear the difference in the other room. ;) But, with these IC's, sibilance was more pronounced. So,,,,, does that mean retain the IC's and dial back some changes in the DAC, or stick with my darker IC's? Also have the treble settings on the Golds, that are in the mix. Fun, fun. :-\
I feel like the KLEI's are letting more through, and therefore I could have gone a smidge too far with the dac. It's getting to the pointy end of dialling in the dac (on this system/room) now.
Rule 101, if you change something and get more sibilance then that usually goes hand in hand with 'detail' 'transparency' etc etc.
So then the challenge is to identify whether:
a/ there is actually more real transparency and the sibilance is being 'let through' as a result, or
b/ the added sibilance is fooling you into believing there is more transparency through added 'fake' detail.
If you can get a handle on these types of scenarios, you've got good ears, or just a lot of experience.
To me, the right decisions when doing this sort of analysis is more important for moving forward in the big scheme of things than lots of floury
audiophile descriptive terms that don't usually mean a lot. :)
One thing I'd like to know is are these interconnect shielded?
Z
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Rule 101, if you change something and get more sibilance then that usually goes hand in hand with 'detail' 'transparency' etc etc.
So then the challenge is to identify whether:
a/ there is actually more real transparency and the sibilance is being 'let through' as a result, or
b/ the added sibilance is fooling you into believing there is more transparency through added 'fake' detail.
I havent been able to pin point a or b just yet. I will say that the clarity I was getting didnt feel fake, there was inner detail in the music that didnt sound artificial to my ears, some very nice texture coming through, throughout the range. There was just the very top end wart, that drew attention to itself. I need to experiment some more.
To me, the right decisions when doing this sort of analysis is more important for moving forward in the big scheme of things than lots of floury
audiophile descriptive terms that don't usually mean a lot. :)
hehe, :D , I dont mind floury terms. For example, ask Steven an opinion and he often says "it doesnt sound like real music !!" :-\ ??? ::) Half the fun is trying to derive meaning from the words of wisdom. 8) [he didnt say that about the dac this time :)]
One thing I'd like to know is are these interconnect shielded?
They were a new KLEI design that Craig bought around. Details of what is in them are not shared by KE, but they felt light, I had to be very delicate with them. My guess is no shielding. They were only here for his visit. I'd like to try the stock gZero6 cables, and play around a little further.
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On Rawls visit last week, he gave me a useful tip. He was peering into the dac, looking at the changes I had made, and I could see the cogs cranking away, and then he came out with the tip to try.
The way I had run the i2s wires from input sockets to receiver chip socket on the dac board could be improved. I had run twisted pairs from each socket around the top of the case, and down into the dac board. At the dacboard end I had twisted the ground wires together and plugged them into the dac board. (did all this with Steven)
Here's how it was.....
(http://dl.dropboxusercontent.com/u/1370915/Audio/Gear/kdac_i2s_internals.JPG)
You can see the i2s sockets in the top middle, the wires running up, then they pop out on the right going into the dac board.
What Rawl suggested was;
- dont run twisted pairs
- only use 1 ground (from the 3 x sockets, because they are already joined at the transport end)
- take them direct from input sockets to the dac board in free air across, dont run them around the outside.
I dont have alot of time for tuning/tinkering activities, my days/nights are consumed doing other things. But I happened to fall out of bed an hour early this morning, and decided to try his change.
Here is how it looks now,,,,,,
(http://dl.dropboxusercontent.com/u/1370915/Audio/Gear/MyKiller/20140913_081759.jpg)
The picture is a bit of an optical illusion. The i2s wires are not as close to the tubes, as they look in that photo. They are a good couple of inches away.
Everything still works. Is it better? yeah, in the usual i2s way, more coherency and clarity.
Thanks Rawl ! :)
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I'd like to try the stock gZero6 cables, and play around a little further.
Ok, gZero6 cables are in. And they sound good. I needed to do a little bit of tuning, but there is a nice balance now.
1 new problem is there is more noticable system hum. Given the feel of these cables, i'm pretty sure they are not shielded. Could be either hum that was there, and the cables are more transparently letting it through, or they are adding to it by picking up environmentals. The IC's they replaced are shielded.
There are always pros/cons. I'll try running them via a different path.