Mark,
The PCBs are still available and you can PM to me your request.
For the parts you should PM to carlsor.
Regards,
Enrico
marktd,
I sure would like to see someone do one original single board build of standard parts and one DAC/Main Board with every proven upgrade from the forums on it for comparison. It is much easier to install the better components right away.
I sure would like to see someone do one original single board build of standard parts and one DAC/Main Board with every proven upgrade from the forums on it for comparison. It is much easier to install the better components right away.
Hi Ross,
Is it of any importance that my CSS assemblys messure between 0,399 and 0,401 mA? So not exactly 0,400. Have a two-decker, so I could mix a bit in a such a way that the average for left and right is about the same.
Ed
Is it of any importance that my CSS assemblys messure between 0,399 and 0,401 mA? So not exactly 0,400. Have a two-decker, so I could mix a bit in a such a way that the average for left and right is about the same.
Ed
CCS Meaurements
A difference of 0.001ma is only 0.25% of 0.400ma. I'm sure the variation between PCM1794 chips is much greater than this. The 6K resistors the CCS boards replace are 1% precision. No matter how you "mix" CCS boards at this level of accuracy - there wont be any audible difference.
A difference of 0.001ma is only 0.25% of 0.400ma. I'm sure the variation between PCM1794 chips is much greater than this. The 6K resistors the CCS boards replace are 1% precision. No matter how you "mix" CCS boards at this level of accuracy - there wont be any audible difference.
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bias on pin 20
I had a light "shifting" in stereo balance because there was a 0,400 on one chip and 0,401 on the other. However I have one deck only.
I had a light "shifting" in stereo balance because there was a 0,400 on one chip and 0,401 on the other. However I have one deck only.
What would you like to learn from this?
I have done extended modifications and comparisons and use a double board red dac and a 4 board blue dac with different mods. In the last dddac meeting we also heard a lot of different builds.
So maybe I can help you out?
And I have a red board bog standard two boarder to compare with my souped up separate analogue and digital supply single boarder
David
More PPS film cap results
I suggested to a friend near me in Florida, USA that he replace all the PET bypass film caps in his DDDAC SPDIF main board with 0.068uf PPS caps. His DAC already has nearly all the other upgrades possible. He bought a bunch of Kemet PPS 0.068uf film caps and installed them. He called me this week to tell me that within 5 seconds he heard a distinct change in the sound – all good! He was expecting maybe a slight change in sq, but to him this change was at least as big from going from the standard power supply to a shunt power supply on the analog. The mid and lower bass had a "chunky" solid sound. From top to bottom the music sounded more pure. He said his DAC was great sounding before this last change but now it rivaled the sound of $20,000 DACs he had heard!
I was reluctant to report that the deep bass sounded more pronounced by putting PPS bypass caps everywhere in the digital circuits, but my friend, who has better hearing than I do, heard this too. Now when I hear a jazz musician slap the stings on his double bass I can feel the deep thump and gutty string scraping. I’ve given up trying to come up with explanations how different bypass caps on the digital circuits can affect the deep bass – it just does.
I highly recommend installing 0.068uf PPS film bypass caps (Mouser - SMR5683J100J03L4) on all digital circuits as part of the original DAC and main board build or rebuild. You can read earlier posts with pics on PPS caps here: http://www.diyaudio.com/forums/digi...pcm1794-waveio-usb-input-428.html#post4263256 and http://www.diyaudio.com/forums/digi...e-board-pcm1794-nos-dddac-42.html#post4239418
I suggested to a friend near me in Florida, USA that he replace all the PET bypass film caps in his DDDAC SPDIF main board with 0.068uf PPS caps. His DAC already has nearly all the other upgrades possible. He bought a bunch of Kemet PPS 0.068uf film caps and installed them. He called me this week to tell me that within 5 seconds he heard a distinct change in the sound – all good! He was expecting maybe a slight change in sq, but to him this change was at least as big from going from the standard power supply to a shunt power supply on the analog. The mid and lower bass had a "chunky" solid sound. From top to bottom the music sounded more pure. He said his DAC was great sounding before this last change but now it rivaled the sound of $20,000 DACs he had heard!
I was reluctant to report that the deep bass sounded more pronounced by putting PPS bypass caps everywhere in the digital circuits, but my friend, who has better hearing than I do, heard this too. Now when I hear a jazz musician slap the stings on his double bass I can feel the deep thump and gutty string scraping. I’ve given up trying to come up with explanations how different bypass caps on the digital circuits can affect the deep bass – it just does.
I highly recommend installing 0.068uf PPS film bypass caps (Mouser - SMR5683J100J03L4) on all digital circuits as part of the original DAC and main board build or rebuild. You can read earlier posts with pics on PPS caps here: http://www.diyaudio.com/forums/digi...pcm1794-waveio-usb-input-428.html#post4263256 and http://www.diyaudio.com/forums/digi...e-board-pcm1794-nos-dddac-42.html#post4239418
Hello Ross,
I can't confirm any of the differences in sq as my built is going to be made with all mods from the beginning of his life, but I took your advices 🙂
Thanks again.
Couldn't get the 1uF for the Tent clock, with simular size. Working on it though.
I can't confirm any of the differences in sq as my built is going to be made with all mods from the beginning of his life, but I took your advices 🙂
Thanks again.
Couldn't get the 1uF for the Tent clock, with simular size. Working on it though.
Hi,
I see you refer to only the digital circuit bypass caps on the motherboard. Did you update any of the bypass caps on the DAC boards?
Thanks
Simon
Any recommendations on IV resistors you guys have used please? This will be for a single DAC module - thanks
Yes. C28 and C30 at Vdd on the DAC board may be the most important digital caps to replace.
Regarding IV resistors - I have had excellent results with Tantalums and Susumu RG SMD resistors on my single board DACs. Switching from the Dales to the Susumu's has been reported to improve musical clarity. I have some extra Susumu RG SMD resistors and adhesive foil if anyone is interested. See http://www.diyaudio.com/forums/digi...e-board-pcm1794-nos-dddac-32.html#post4202948
Enrico, Carlsor, got all my bits now! Many thanks for putting all this together for the group
David
David
