CM6631 usb audio interface .... any good?

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A

Archimedes21

Member
Joined 2013
f2a said:
Hello everyone , i have the same board like the one at Post #12 .With the original FW the RCA and I2s output works but in I2s i hear only the left side in all resulutions. I tried the circuit from post #6 http://www.diyaudio.com/forums/digital-line-level/100959-left-justified-i2s-philips-i2s-converter.html , i hear now on the left and right side with much noise ... My DAC use in original a PCM2706 with Philips I2s output . The DAC accept max 24Bit/174MHz . In 16Bit/44.1Mhz to 32Bit/192kHz is no change . Has anybody a idea ? I'm a little Rookey in electronics, but i can built everything ;-) Can anybody say me why the I2s output from the CM6631 is different like the one from the PCM2706 then i use the same resulution (16/44.1) ? Is I2s not the same? Thank you for a Little help and sorry for My BAD english :) Have a nice day :)
Click to expand...

I can confirm the same issue but with a diffrent board. My board is from breeze audio (CM6631A). The board is connected via I2S with a TAS3308 DSP. In sample rates 44.1/48 i can hear actually the audio, but there is a lot of noise (distortion). Interestingly, when i upsample the audio via reclock to 88.2 oder 96 Khz, the noise is completly gone. So the I2S connection seems to be fine... I assume that the CM6631A puts out the wrong Bitclock (SCLK) in 44.1/48 Khz mode. This was discovered by HifiDuno in his Blog (cm6631 | Search Results | H i F i D U I N O ). He states, that the Bitclock for 44.1/48 is 128 fs, but it should be 64 fs for those sample rates.

Any ideas how to fix this? Maybe a new firmware can fix this? The connection via i2s works with higher sample rates, so i dont think the error has to be the i2s connection to the dsp.

Thanks!

BTW, the cm6631 and all clocks are running on battery, just feeding the 3.3 Voltregulators with 4 1,2 V NimH batteries and it much better compared to SMPS.
 
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patrykvel

Member
Joined 2011
Hi
Right now i'm using CM6631 with Asus firmware which solved couple problems. There are thoese.
1. WASAPI and ASIO didn't worked on SPDIF output. Kernel streaming was unavailable.
2. Converter didn't send any signal when music was not playing, so DAC lost synch. My DACs dont have mute control so i could hear something like white noise.
3. SPDIF output was recognised in windows like an extra SDPIF output. Not like "speakers" in all other converters and USB receivers.

My friends would also buy converter with CM6631/A, but without thoese problem which had CM6631 with firmware from Cmedia. Right now it's impossible to buy converter with older CM6631(out of stock) and as far as I now firmware from CM6631 didn't fits to CM6631A.
Are there any other solutions?

Thanks for any help.
 
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wklie

Member
Joined 2013
patrykvel said:
Hi
1. WASAPI and ASIO didn't worked on SPDIF output. Kernel streaming was unavailable.
2. Converter didn't send any signal when music was not playing, so DAC lost synch. My DACs dont have mute control so i could hear something like white noise.
3. SPDIF output was recognised in windows like an extra SDPIF output. Not like "speakers" in all other converters and USB receivers.

My friends would also buy converter with CM6631/A, but without thoese problem which had CM6631 with firmware from Cmedia. Right now it's impossible to buy converter with older CM6631(out of stock) and as far as I now firmware from CM6631 didn't fits to CM6631A.
Click to expand...

See the summary I posted in
http://www.diyaudio.com/forums/digi...-audio-interface-any-good-21.html#post3385322

and firmwares for both CM6631 and CM6631A in
http://www.diyaudio.com/forums/digi...-audio-interface-any-good-26.html#post3400036

Briefly, (1) I use CM6631A firmware 0108 PID 0314 Firmware, it will output to SPDIF via WASAPI (push) but not via ASIO. It also can passthrough DTS and AC3 correctly. (3) The SPDIF output shows up as SPDIF, not speakers.
 
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wklie

Member
Joined 2013
W

wklie

Member
Joined 2013
Radian said:
The flash utility calls for a .hex file but I can't find it, not even with a ".hex"
search on my computer. That's weired. Does it not come with the FW update package?
Click to expand...

Depends on what package you're referring to. The link Xonar Essence One - Sound Cards and Digital-to-Analog Converters - ASUS shows four files under Windows XP - Firmware. Two are upgrade tools. One is MCU firmware. I think the USB firmware is what you need:
Essence One USB F/W Version:0111
fix bug:The compatibility problem with ASUS blue-ray(SPDIF).
Important: When updating firmware, please do not switch off power. And please plug in to USB 2.0 port.

Use a Windows XP PC to update the firmware.
 
H

Heaby

Member
Joined 2013
About a week ago I bought this item: 32 192 DAC CM6631 CS4398 USB to Coax Analog Headphone Output | eBay I've only had it for about a day but it's already been a bit of a hassle trying to get it to work. At first the linked drivers weren't the correct ones so after searching for the correct ones I discovered this thread and found a driver that works, namely CM6631 Emotiva XDA-2 Unified Windows USB Driver. After that it worked just fine, all the different resolutions were selectable all the way up to 24/192 (not 32 though. is that right?). In foobar however I could select 32bit in the asio control panel. Anyway, at first I had only my headphones connected and the device was identifying the connected equipment as headphones. I then figured I should connect my speakers with rca and did so and the device then correctly identified them as speakers. But after that, I can only choose 16/44 & 16/48, both in sound controlpanel and in foobar. Disconnecting the speakers and only using my headphones makes no difference and the device still says speakers are connected. Why has this happened? I find it hard to believe the unit could be faulty since it worked at first. Regarding firmware, this is what it says: USB\VID_0D8C&PID_0319&REV_0101&MI_00 Is it a firmware problem perhaps? Could I have damaged the unit when I connected my speakers? I connected them through a receiver which was in standby if that has any bearing. Any help is much appreciated.
 
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