CM6631 usb audio interface .... any good ?

[Nanoloop]

If there is not enough power, it maybe cheap cable - aluminum with copper coat.

[terranigma]

Hello all,

I'm trying to figure out what is the difference between plain 6631 and 6631A. Is there any confirmed format and performance issue between them? I can't find a 6631A board containing 12M, 45.1584M and 49.152M oscillators separately. Some plain 6631 boards have all crystals seaparately.

[KlipschKid]

Originally Posted by terranigma

Hello all,

I'm trying to figure out what is the difference between plain 6631 and 6631A. Is there any confirmed format and performance issue between them? I can't find a 6631A board containing 12M, 45.1584M and 49.152M oscillators separately. Some plain 6631 boards have all crystals seaparately.

Try reading before asking. CM6631 usb audio interface .... any good ?

All the boards have 3 oscillators. I wonder if you have problems reading and seeing things ?

[terranigma]

Originally Posted by KlipschKid

Try reading before asking. CM6631 usb audio interface .... any good ?

All the boards have 3 oscillators. I wonder if you have problems reading and seeing things ?

I did it but I couldn't find a particular answer within two pages of search results.

For example, description of 6631A item below tells about only two dedicated oscillators. 12M usb oscillator isn't well recognizable in photo.

24bit 192kHz USB to I2S SPDIF PCB CM6631 with Ultralow Noise 6 5UV Regulator | eBay

Thank you anyway, despite your naive rudeness.

[wklie]

Originally Posted by terranigma

For example, description of 6631A item below tells about only two dedicated oscillators. 12M usb oscillator isn't well recognizable in photo.

CM6631 data sheet states that "Only single 12MHz crystal input is required (embedded PLL function) or optional oscillator inputs for 49.152MHz and 45.158MHz". Perhaps that's why it's not necessary to advertise the mandatory presence of the 12MHz oscillator.

[KlipschKid]

Originally Posted by wklie

About my issues with ASIO:
- My unit came with firmware 0108 PID 0x0314.

I just got this cheap one on Taobao because it is the cheapest I found with i2s. It also has 0108/0314, which is 24bit, but I need 32bit for digital volume control. It has a very noisy regulator. XOs, esp 12Mhz, look low grade too.

Originally Posted by wklie

- Using Windows XP I was able to switch between these two firmwares.

Yes me too, thanks to your instructions :

Originally Posted by wklie

CM6631A Firmware 0101 VID 0x0D8C PID 0x0319:
https://docs.google.com/file/d/0B_6Y...it?usp=sharing

CM6631A Firmware 0108 VID 0x0D8C PID 0x0314:
https://docs.google.com/file/d/0B_6Y...it?usp=sharing

To be used with the flash update tool found in the CM6631 Firmware 2203 package VID 0x0D8C PID 0x0309 on Windows XP _ONLY_:
http://www.nutsaudio.com/driver/CM6631_Firmware.zip

Instructions:
- A Windows XP PC is needed (XP compatibility mode on newer Windows does not work - do not try it)
- Connect the CM6631(A) unit to a USB 2.0 port at the back of the PC, do not use the front ports even if available
- Run the flash update tool
- Erase firmware
- Unplug the CM6631(A) unit then reconnect it again
- Update using a new firmware hex file
- If a File Format Error or a Flash Error is shown, reconnect the unit again and flash it again

So now I have 32 bit with i2s and spdif, similar to the diyinhk cards.

Originally Posted by wklie

I found that firmware 0101 PID 0x0319 can output to SPDIF via CMedia ASIO, but it will never passthrough DTS and AC3 because the unit shows up only as Speakers instead of SPDIF on Windows 7 x64.

Mine shows two channels in asio, both spkout, and it allows 32bit/192khz. The diyinhk cards show as spdfout, but it seems that functionally the ASIO works the same.

Originally Posted by wklie

Firmware 0108 PID 0x0314, using current drivers, will not output to SPDIF via ASIO, but it can passthrough DTS and AC3 correctly. With this firmware, SPDIF, Speakers and Heaphones show up on Windows 7 x64 even though my unit does not have Speakers or Headphone output. DTS passthrough using both DirectSound in MPC-HC x64 or WASAPI in MPC-HC x32 + ReClock are tested to be working normally.

This showed 4 channels in ASIO, spkout and hdphout (or something like that) and was limited to 24 bit so it was not as good for me. It did not show any spdfout in the asio driver.

Originally Posted by wklie

Thanks to tdtsai and everyone who helped.

My sincere thanks to all too ! I just need to improve the regulator and I'll be satisfied.

[Radian]

Originally Posted by KlipschKid

I just got this cheap one on Taobao because it is the cheapest I found with i2s. It also has 0108/0314, which is 24bit, but I need 32bit for digital volume control. It has a very noisy regulator. XOs, esp 12Mhz, look low grade too.................
....................My sincere thanks to all too ! I just need to improve the regulator and I'll be satisfied.

Didn't you have two 6631 already at hand?
I thought to get I2S out of the 6631 it just needs to be flashed with the right firmware.
I ordered the exact board and wondered if I did the right thing.
Mine is gonna be hooked up to an AK4396 fed by A123 Batteries.
Can you recommed any XOs you tried? There are so many that claim 1ppm
accuracy but unless someone has tried them against alternatives it is
impossible to know what to get.
Have you tried running two of those boards from one XO to see if a four or
six way system can be build?
Routing to different sound devices after the digital crossover shouldn't be
to much of a problem with todays software options.

Greets,
Klaus

[KlipschKid]

Hi,

I have four now - 2 cm6631 and 2 cm6631a. I have many dacs..... akm4399, es9018, dual ad1955, wm8741, cs4398... and more. I need more ears. :-)

Good cheap parts are Fox Xpresso and Euroquartz xo91. PPM is not so important - this is the measure of stability. More important is phase noise, usually measured in ps, but for some very special clocks, it can be measured in fs. Crystek CCHD-957 has lowest phase noise for 45/49 clocks. Tent labs has lowest phase noise for 12mhz. Also, some NDK clocks have very low phase noise but they are special NDK and hard to find outside japan. But to get fs phase noise needs very low noise power supply, excellent pcb, design, etc. To route out lock to many devices needs a fanout buffer and a very good pcb.

my hifi uses a class-a line level crossover for bi-amping, so i don't need to use multiple cards for a pc/digital crossover.

I also have this as a usb/spdif to spdif/i2s :

http://myl8test.wordpress.com/audio/...fi2s-and-asrc/

[wklie]

Originally Posted by KlipschKid

The diyinhk cards show as spdfout, but it seems that functionally the ASIO works the same.

If it shows up in Windows as SPDIF device, it shows the "Supported Formats" tab (which contains options of DTS Audio and Dolby Digital and sample rates) in playback device properties, right? (When I was using 0101 PID 0319 this tab does not show up.)

Please tell me what is the value in Windows Device Manager -> USB2.0 High-Speed True HD Audio (i.e. the diyinhk device) -> Properties -> Details -> Hardware Ids

Thanks a lot!

[JarekC]

Hi,

Can anyone read USB descriptor of converter based on CM6613/CM6631A.
Here is free software-descriptor dumper to do it. http://www.thesycon.de/tdd/tdd.exe
(no instalation needed)
Then we can compare the versions differences.

BR
JarekC