CM6631 with ES9023?

sure. then again, the tenor can be isolated on the usb side at 96khz whereas the cm will have to run at 48khz even if you can make it work isolated. Stick a tent labs xo on the tenor and it's a whole different thing.

That es9023 looks okay but it has like US$10 parts for $S$50, and the cm6631 looks about as crap as any i've seen. it has noisy regulators and cheap 12mhz crystal and there's probably bad routing, grounding, etc.

So in theory it should sound better but in reality it may not. Buy it and find out. It's only money.


2005-10-20 12:57 pm
I ended up buying these pcbs.....

24bit 192kHz USB to I2S / SPDIF PCB CM6631 with ultralow noise 6.5uV regulator | eBay

DAC-24192-ULN, 24Bit/192KHz DAC, I2S Input, Ultra Low Noise Regulator Circuit | eBay

I downloaded the diyinhk cm6631a drivers but had glitches at all sampling rates on two windows 7 64bit laptops (not normal laptop noise, actual interruptions to the stream). Rebooting into Ubuntu has solved the problem completely, and the Dac sounds nice - quite solid sounding yet open and clean.


2005-10-20 12:57 pm
Photo below....


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Hugh Jazz

2013-02-15 5:19 am
Sharpi31 - good project.

Can I suggest ?

It is good to twist audio wires into a twisted pair. Your wires have not any twist. Twist power/ground together. Twist signal/ground together.
It is good for digital to have one ground wire for every signal wire. You can use flat cable or twisted pair. All short as possible.

ES9023 can sound better with asynch mclk - 50Mhz SAW from Epson use as mclk into DAC. Maybe you want to try ? You change quite easy and it is not expensive.

Also to try, if you want, is output cap (green Wima ?). Relcap RTE must sound good. Mundorf also. But this not so cheap.
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