CM6631 usb audio interface .... any good?

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triode_al

triode_al

Member
Joined 2004
Where is it isolated?

My question about the diyinkh 'Isolated 24bit 192kHz USB to I2S/SPDIF CM6631A PCB' is where it is isolated:
  1. at the output so just 'before' the output plug and after the DSP
  2. at the input just 'behind' the USB plug, so to say

  1. the first quickly adding some jitter again.
    Sorry, I can't find the documentation :confused: it my laziness today to ask.

    albert
 
UnixMan

UnixMan

Member
Joined 2005
audiofaidate.org
triode_al said:
where it is isolated:
  1. at the output so just 'before' the output plug and after the DSP
the first quickly adding some jitter again.
Click to expand...
NOT if you do it the right way! ;)

That is, you have to put the clock(s) "on the clean side", send the required clock back to the USB interface through another isolator and do (synchronous) reclock the I2S signals after the isolators. :cool:

As properly done by: "USB Audio interface | ABC PCB"
 

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UnixMan

UnixMan

Member
Joined 2005
audiofaidate.org
bobbybland said:
Hi
I've got one of DIYINHK's Isolated 24bit 192kHz USB to I2S/SPDIF CM6631A PCB replacing the faulty first half of an old Cambridge Audio DAC3. All is well except that anything over 96khz is very distorted. Does anyone have any suggestions? I am running windows 7 via usb2 to the four tda1541a, connected with LRCK, BCK and DATA.
Click to expand...
If it behaves in the same way as the non-isolated one, I'm afraid that the problem may arise from the different frame clock which is used for different sample rates. At s/r above 96KHz it uses a ~44MHz clock (while it's ~22MHz@96K and, IIRC, ~11MHz@48K).

A clock >40MHz may be good for the Sabre (for which this interface seems to have been specifically designed), but many DACs do not like it. Mine does not even work at all with it (when s/r is >96KHz).
 
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J

jkorten

Member
Joined 2012
abioqaas said:
I received a "Breeze Audio" CM6631 USB-SPDFI/Optical out box today but I'm having problems with it.

My rig is running Windows 8 and I used the Emotiva XDA-2 drivers from this thread, they were the only ones that worked on Windows 8 for me. Driver installation went fine, I can see the device and get audio out of it.

My FW revision is 2206 and I noticed that indeed I did not get audio out when running in ASIO mode. I was able to get WASAPI + Foobar working though.

Here comes the problem: I can't get some sample rates to work, it's really weird. Multiples of 44.1kHz work, for example 88.2kHz and 176.4kHz work. Multiples of 48kHz don't work so for example 96kHz and 192kHz don't work. Or they work, kind of. I get audio but there is crackle and noise on top. Sounds almost like some kind of clocking problem?

My setup is:

USB - Breeze Audio box - Aune X1 MK2 coax SPDIF in

I've ruled out the Aune as the cause as it works perfectly with my mobo SPDIF out - I can get every sample rate working from 44.1kHz up to 192kHz / 24-bit.
Click to expand...

Did you go to the control panel, sound device and choose advanced settings and enable the hi sample rates?
 
W

wklie

Member
Joined 2013
gungstar said:
originaly it comes with ver 0107. now it flashed with one of the oem fw taken from this thread and this is the reason why i searching for original fw because now no sound from all outs
Click to expand...

I don't see Asus posting firmware for ROG Thunderbolt Audio/LAN combo card. However, if you can get the Asus Xonar Essence One firmware 0109 or 0111 to flash on your card, I think there's a chance it may work.
 
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E

Earbound

Member
Joined 2012
I have just received an CM6631A. I have installed a driver on my windows 7 laptop and I have no problem.However, on my MAC mini running Mountain Lion, I can´t get it to work at all. I use Audirvana and the JRiver beta for MAC, but it do not work with any o them. What is the problem. I have not a clue.
 
W

wklie

Member
Joined 2013
Earbound said:
I have just received an CM6631A. I have installed a driver on my windows 7 laptop and I have no problem.However, on my MAC mini running Mountain Lion, I can´t get it to work at all. I use Audirvana and the JRiver beta for MAC, but it do not work with any o them. What is the problem. I have not a clue.
Click to expand...

Several things to try:
- Read http://emotiva.com/resources/media/xda2/Emotiva_XDA-2_Apple_Drivers.pdf
- Connect the CM6631A to your Mac before powering up the Mac.
- Try each and every USB port.
- If you have an external power source for the CM6631A device, use it.
- On page 29 post #284 bvs has discovered a solution for Mac compatibility by removing a reset chip from the device.
 
E

Earbound

Member
Joined 2012
wklie said:
Several things to try:
- Read http://emotiva.com/resources/media/xda2/Emotiva_XDA-2_Apple_Drivers.pdf
- Connect the CM6631A to your Mac before powering up the Mac.
- Try each and every USB port.
- If you have an external power source for the CM6631A device, use it.
- On page 29 post #284 bvs has discovered a solution for Mac compatibility by removing a reset chip from the device.
Click to expand...

I have an external power supply, but I have not been able to figure out what voltage the CM6631A needs/takes. I don´t want to toast it.
The strange thing is that others that have been reporting problems can play 16/44,1 files without problem, but I can´t play 16/44,1 either.
 
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