Celibidache DAC PCB out to manufacture
For all you guys actively awaiting the next DAC, here's a preview as the PCB data has gone down to JLC today.
As its pretty tight we've gone for 4 layers this time. The plug-in filter will be a custom 9th order one - not electrically compatible with Deca DAC. Same mechanical footprint though.
For all you guys actively awaiting the next DAC, here's a preview as the PCB data has gone down to JLC today.
As its pretty tight we've gone for 4 layers this time. The plug-in filter will be a custom 9th order one - not electrically compatible with Deca DAC. Same mechanical footprint though.
Attachments
Then empire's troups are on their way LOL
Looks great and sounds promising, well done!
Please keep us posted re listening impressions
Claude
Looks great and sounds promising, well done!
Please keep us posted re listening impressions
Claude
Celibidache
I curiously hope this new dac will bring some of the magic that Celibidache could put in his concerts...
I curiously hope this new dac will bring some of the magic that Celibidache could put in his concerts...
You raise a very interesting point there @ed. In this interview Celibidache expresses his skepticism that recordings can really capture what goes on in a performance. Around 9mins in the interviewer asks 'Even digital recordings?' and he says they're even worse at capturing the performance than the older tech because 'they split the sound up into 1,600,000 parts'. Its a fascinating conversation.
Sergiu Celibidache on his Philosophy of Music - YouTube
Sergiu Celibidache on his Philosophy of Music - YouTube
Thanks for sharing this!
Excellent interview that shows once again that he was not a mere musician or conductor, but a philosopher; musicologist and many more. What he says makes a lot of sense, eventhough there are some possible arguments between the mathematic theory and the real life. But I love it.
His french and german are obviously excellent (he didn't just spend time in these countries). I am lucky enough to be native in both and can tell that the english subtitles are not doing him any justice - he goes farther than these and is far more subtle, they aren't capturing everything.
The only negative I can see with such a fascinating conductor, which like all philosopher has a "strong sometimes stubborn mind", were his hard comments and acts towards women in music. My mother is probably on a par with him (in another music category and with less glory), she would jump sky high... but agree with him on most other bits probably LOL
Shouldn't put us off from an excellent DAC... your wife can listen to LOL!
Have a nice Sunday
Claude
Excellent interview that shows once again that he was not a mere musician or conductor, but a philosopher; musicologist and many more. What he says makes a lot of sense, eventhough there are some possible arguments between the mathematic theory and the real life. But I love it.
His french and german are obviously excellent (he didn't just spend time in these countries). I am lucky enough to be native in both and can tell that the english subtitles are not doing him any justice - he goes farther than these and is far more subtle, they aren't capturing everything.
The only negative I can see with such a fascinating conductor, which like all philosopher has a "strong sometimes stubborn mind", were his hard comments and acts towards women in music. My mother is probably on a par with him (in another music category and with less glory), she would jump sky high... but agree with him on most other bits probably LOL
Shouldn't put us off from an excellent DAC... your wife can listen to LOL!
Have a nice Sunday
Claude
First PCB prototype of Celibidache plays music - and rather sweetly too. The filter PCB wlll eventually match the baseboard but I still have some old experimental 9th order ones left from Deca DAC development.
Due to the buck regulator for the DAC chips the current consumption is lower than for Deca though the supply voltage is higher (now 24V). So overall, a similar power draw, around 2W.
Due to the buck regulator for the DAC chips the current consumption is lower than for Deca though the supply voltage is higher (now 24V). So overall, a similar power draw, around 2W.
Attachments
I've built 3 Celibidache prototypes now - the third one I've populated only with 12 chips but running at 5.5V. The first two have 20 chips at 3.3V. Both options produce about the same output current but I'm curious if there's any difference in SQ....
Running 20 chips at 5.5V produces too much current for the I/V stage (the SOT-23s in the OPS run too hot) but there is the option of changing the output transistors to SOT-223. Hmmm.
Running 20 chips at 5.5V produces too much current for the I/V stage (the SOT-23s in the OPS run too hot) but there is the option of changing the output transistors to SOT-223. Hmmm.
And, what are the impacts?
20 vs 12 but with higher voltage
Are there any sonic differences?
To be complete it would indeed be nice to compare 20 vs 12 at same voltage...
VERY interesting... as ever!
Claude
20 vs 12 but with higher voltage
Are there any sonic differences?
To be complete it would indeed be nice to compare 20 vs 12 at same voltage...
VERY interesting... as ever!
Claude
If there are differences they aren't obvious ones at first, its gonna take quite a lot of listening to weed them out. Plus my wife hasn't listened yet, she's usually much better at these kinds of puzzles.
I'll ask her if she can squeeze on the SOT-223s then we'll have more flexibility.
I'll ask her if she can squeeze on the SOT-223s then we'll have more flexibility.
Perhaps 12 DACs chip are "already enough" and help avoiding installation issues (length of tracks etc.)?
Then decide at what voltage it sounds best
Your wife will tell 🙂
Have a nice day
Claude
Then decide at what voltage it sounds best
Your wife will tell 🙂
Have a nice day
Claude
Wifey liked 20 DACs better on more intensive listening and so did I - more engaging. The difference is I knew what we were listening to and she didn't so my result is likely subject to bias.
So next question is - is superior SQ a function of quantity of DACs? Does higher voltage degrade SQ?
Comparing 12 chips against 20 at the same voltage is a bit of a skewed test. I'd have to increase the gain for the 12 chips which would likely result in a degradation, higher noise (and higher distortion).
So next question is - is superior SQ a function of quantity of DACs? Does higher voltage degrade SQ?
Comparing 12 chips against 20 at the same voltage is a bit of a skewed test. I'd have to increase the gain for the 12 chips which would likely result in a degradation, higher noise (and higher distortion).
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Well, I undertand indeed the skewed test in that case. However, as an industrial I see that whereas things aren't exactly comparable, at the end what matters is the result and feasability (and other bits) 🙂
In short, if 20 chips are better, still affordable, still packageable, and as a bonus they can live with less voltage which could be a plus, then so be it - it is then a solution that isn't exactly comparable but that includes some intrinsec advantages 🙂
Fascinating...
Claude
PS : note I don't know the layout nor exactly the problem, but should it just be an output voltage story, then for sure (while not seeking absolute sound quality) an acceptable test rig could be performed through a volume pot to adjust levels (and as they are all degreded by the pot at least things are then equal?)
In short, if 20 chips are better, still affordable, still packageable, and as a bonus they can live with less voltage which could be a plus, then so be it - it is then a solution that isn't exactly comparable but that includes some intrinsec advantages 🙂
Fascinating...
Claude
PS : note I don't know the layout nor exactly the problem, but should it just be an output voltage story, then for sure (while not seeking absolute sound quality) an acceptable test rig could be performed through a volume pot to adjust levels (and as they are all degreded by the pot at least things are then equal?)
I figured I can re-jig the 12 DAC prototype into a 20+ chip one, by lowering the supply from 3.3V down to the minimum the chips will accept. While the datasheet says 3V is the lowest, in practice I've had acceptable results down to 2.7V (when running on supercaps) so I'll have a play in that direction to see how it goes. At 2.7V I should be able to try 24 chips.
Mine should arrive in a couple days. Need to order most of the BOM, but have the inductors and opamps in hand 😉
Any updates Vunce? So far I've not heard of anyone building Kubelik from the BOM so I'm curious if you'll be the first.
No movement on Kubelik yet. A few projects currently going on currently, close to ordering the parts though 😉
At 2.7V I should be able to try 24 chips.
24 chips was a bit better so I decided to try 40 next. Which improves things noticeably in the lower registers - bass lines are easier to follow, the background is blacker. How to fit 40 chips on the PCB though (I prototyped 40 chips by stacking them 2 high which is jolly fiddly)? Put half of the chips on the underside? Any other ideas?
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