Hi,
The 6631 show supported formats : encoded formats and sample rates. I haven't seen this with the 31A. The 31A uses a different driver and maybe there is more than one 31A driver too ?
Diyinhk CM6631 (not A) in nutsaduio firmware tool says VID 0D8C, PID 0309, FW2203. This device does i2s and spdif output at the same time. In Foobar, it has two output channels: SPDIFOut00_00 and SPDIFOut00_01. The driver version is 7.0.11.80 and hardware ids are
USB\VID_0D8C&PID_0309&REV_2203&MI_00
USB\VID_0D8C&PID_0309&MI_00
Is this what you wanted ?
cheers, Tom
To see the encoded formats and sample rates tab on CM6631A, the firmware 0108 PID 0314 needs to be used. Then DTS/AC3 passthrough can be supported.
Yes, thanks! So your board diyinhk board is CM6631 with Firmware 2203. Their ebay products are upgraded to CM6631A.
BTW, the diyinhk cm6631a have 101 firmware, and they seem to be able to use the same driver above, there's no supported formats control, the outputs are spkout, and hardware ids are
USB\VID_0D8C&PID_0319&REV_0101&MI_00
USB\VID_0D8C&PID_0319&MI_00
I'm not sure I'd describe the A as an upgrade; a change yes. But I haven't heard any difference in sound quality between diyinhk a and non-a and it seems it is a feature change ? Is this summary correct ?
non-a-2203 can do dts and simultaneous outputs, and 32bit, but no 176khz,
a-101 can do simultaneous, 32bit, and 176khz but no dts
a-108 can't do simultaneous or 32bit, but can do 176 and dts
??
Gotta hope they work out how to make a cm6631b that can do it all.
USB\VID_0D8C&PID_0319&REV_0101&MI_00
USB\VID_0D8C&PID_0319&MI_00
I'm not sure I'd describe the A as an upgrade; a change yes. But I haven't heard any difference in sound quality between diyinhk a and non-a and it seems it is a feature change ? Is this summary correct ?
non-a-2203 can do dts and simultaneous outputs, and 32bit, but no 176khz,
a-101 can do simultaneous, 32bit, and 176khz but no dts
a-108 can't do simultaneous or 32bit, but can do 176 and dts
??
Gotta hope they work out how to make a cm6631b that can do it all.
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My device uses these "1ppm" TCXO:
http://item.taobao.com/item.htm?spm=a1z10.3.w948178642.10.KJMpnJ&id=13830312889&
I have wondered why these oscillators seem cheaper than others with higher ppm. So ppm being "unimportant" is the answer...
PPM is important = higher grade crystals have lower ppm but people don't hear ppm. They hear phase noise, and it is basically jitter - so lower phase noise gives better definition. What can make a difference is how clean the power is for those 1ppm clocks. The card I bought on taobao doesn't sound as good as diyinhk ones - less definition - clocks might be inferior and the regulator is hugely inferior. So a power change is necessary..... but it's going to get isolated and then re-clocked with some flipflops so I hope it won't matter that much. I'm waiting on a group buy that has isolators/flipflops... eager to try that out.
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This seems correct.
Added ASIO information to your summary:
non-a-2203 can do dts and simultaneous outputs, and 32bit, ASIO, but no 176khz
a-101 can do simultaneous, 32bit, ASIO, and 176khz but no dts
a-108 can't do simultaneous or 32bit, but can do 176 and dts while ASIO is only for Speakers/Headphones out not for SPDIF (maybe a future driver can enable the ASIO support for SPDIF)
non-a also has firmware 2205 PID 0304 which cannot output to SPDIF via ASIO. People claims that it sounds worse than 2203, possibly due to lowering of I2S to 192fs (?) Source in Chinese: http://bbs.hifidiy.net/viewthread.php?tid=709432
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192fs ? I cannot follow that logic. fs is sampling frequency, and 192 represents sample freq to mclk ratio ? maybe they mean 192khz is the fs ? but lowering ??? For 44.1khz and a 45mhz clock, you get 1024fs. some datasheets for dac ic recommend 256 to 512fs and this is set by the oscillators, not firmware. and that device looks crap. So that thread is very much an unsupported claim. maybe they mean 32 bit sounds better than 24 bit ? I'd expect 32 bit to have the potential to sound better than 24 bit, but whether it did or not..... so different firmware could definitely sound different... but does it ? easiest way to check would be to run rmaa on spdif with a 32-bit test rig. I don't have this.
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Here's RMAA test results of various USB->SPDIF chips. Although the discussions are in Chinese, all the RMAA screenshots are in English and self-explanatory:
USB->SPDIFоƬ²»ÍêÈ«RMAA²âÊÔ¡£ÄÚº¬ÈÈÃŵÄCM6631²âÊÔ - ÒôÏìDIYÂÛ̳ - HIFIDIYÂÛ̳ - Powered by Discuz!
There is a follow up thread that talks about someone modified the CM6631 2205 firmware to correct the Intermodulation distortion anomaly, but I'm unable to find it for now - my google skills are failing me.
Hi,
One again.
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
One again.
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
I can't, and to be honest, even if I could, I wouldn't spend my time trawling through lines of code looking for differences. Sorry, you need someone far less busy and totally into coding. That's not me.
Here's RMAA test results of various USB->SPDIF chips. Although the discussions are in Chinese, all the RMAA screenshots are in English and self-explanatory:
USB->SPDIFоƬ²»ÍêÈ«RMAA²âÊÔ¡£ÄÚº¬ÈÈÃŵÄCM6631²âÊÔ - ÒôÏìDIYÂÛ̳ - HIFIDIYÂÛ̳ - Powered by Discuz!
There is a follow up thread that talks about someone modified the CM6631 2205 firmware to correct the Intermodulation distortion anomaly, but I'm unable to find it for now - my google skills are failing me.
Unfortunately his rig isn't up to the job. He's only able to test up to 24 bits, which could be 144dB but his test gear seems limited to 113dB, where everything hits a brick wall.
Even the taobao seller I got my cheapo card from claims he gets 120db from his into an EMU that can do 140dB, and it sounds worse than the diyinhk one.
It seems the bad imd of the cm6631 was because he was running a single 12mhz crystal and he's suggesting adding a 45 and 49 ? Where did you read about modding the firmware ?
If you want to know, then it really has to be tested on 32bit digital rig because the major difference between the firmwares is 24 and 32 bit operation.
jarek - is there a reason you need this ? is there a reason you can't do it yourself ? If I may be blunt, this is DIYaudio, not get-someone-else-to-do-it-audio. if you have a problem or something, then I'll try to help. but I wonder why you insist on asking others to do something it seems you already know how to do. Care to explain ?
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I ran it and got a really long output for my 0108 firmware. If you need it you can PM me your e-mail address.
Interestingly enough it reports a few sections of descriptor errors:
Endpoint Descriptor (Audio):
------------------------------
*** ERROR: Invalid descriptor length 0x07
Hex dump:
0x07 0x05 0x01 0x02 0x40 0x00 0x00
Endpoint Descriptor (Audio):
------------------------------
*** ERROR: Invalid descriptor length 0x07
Hex dump:
0x07 0x05 0x82 0x02 0x40 0x00 0x00
Found two other firmware for CM6631. Note the PID difference compared to the nutsaudio 2203.
CM6631 Firmware 2205 PID 0304
http://bbs.hifidiy.net/attachment.p...d928cb4f57dbe5d12a57f&t=1362670760&sid=lWbFc2
CM6631 Firmware 2206 PID 0304
http://bbs.hifidiy.net/attachment.p...e62cfdc08c2ed3f95d70d&t=1362670760&sid=lWbFc2
I cannot check these firmware, so upgrade at your own risk. These are the differences I've read but cannot confirm:
- 2205 and 2206 PID 0304 add 88.2kHz support missing from 2203
- 2203 PID 0309 does simultaneous I2S/SPDIF output, whereas 2205/2206 PID 0304 only outputs I2S but not SPDIF via ASIO (similar to CM6631A 0108 PID 0314?)
- Multiple reports state that 2203 gives better audio quality than 2205/2206.
- Note that only the two PID 03x9 firmwares for CM6631 and CM6631A are named as UsbDAC, the other PID 03x4 firmwares are not.
If anyone try out these firmware, please post your findings.
thanks wklie for your contribution
unfortunatelly there are so many combinations of firmware and drivers with this board that add or delete certain functionalities that I ordered an Amanero board that it's supposed to work up to 352 khz out of the box with no problems and lately they also added ASIO support as well and on Linux I see that it won't even need a driver
we'll see about a sound comparison in an A/B test where the rest of the audio chain remains unchanged, only a fast switch between I2S signals and the DAC
unfortunatelly there are so many combinations of firmware and drivers with this board that add or delete certain functionalities that I ordered an Amanero board that it's supposed to work up to 352 khz out of the box with no problems and lately they also added ASIO support as well and on Linux I see that it won't even need a driver
we'll see about a sound comparison in an A/B test where the rest of the audio chain remains unchanged, only a fast switch between I2S signals and the DAC
Are there any usb-asrc-i2s boards out there ? I'd love to get one that uses an fpga to buffer+upsample to 384khz/32bit.
I got this but the usb is 16 bit, so I'm gonna have to change the usb receiver.
USB/SPDIF TO SPDIF/I2S and ASRC | myl8test
wklie - the 2203 is 32 bit, the 2205 and 2206 are 24bit. I'd bet my last kidney the 32 bit firmware sounds better. Did you have fun trawling through the code to find nothing of use ? ;-) If you like that sort of thing, then run the card through the asio @24bit and 192khz (sox resampler is easy if you use foobar and have no hi-res files), and do the dump. then use the direct sound and force 16bit in foobar and 44.1khz and do the dump. then have fun comparing the two ;-) Do you know hex ? http://en.wikipedia.org/wiki/Hexadecimal
I got this but the usb is 16 bit, so I'm gonna have to change the usb receiver.
USB/SPDIF TO SPDIF/I2S and ASRC | myl8test
wklie - the 2203 is 32 bit, the 2205 and 2206 are 24bit. I'd bet my last kidney the 32 bit firmware sounds better. Did you have fun trawling through the code to find nothing of use ? ;-) If you like that sort of thing, then run the card through the asio @24bit and 192khz (sox resampler is easy if you use foobar and have no hi-res files), and do the dump. then use the direct sound and force 16bit in foobar and 44.1khz and do the dump. then have fun comparing the two ;-) Do you know hex ? http://en.wikipedia.org/wiki/Hexadecimal
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I can understand with upsampling or digital volume control 32bit would make a difference. However, if one plays raw 44.1kHz 16bit unchanged without upsampling and without digital volume, do you think the firmware being capable of 32bit makes a difference?
It would depend on the dac. But it can sound better and I'd bet it's the bit depth that is the reason people say one firmware sounds better than another. Then again, maybe the firmware changes the way the buffer/pll operate together, although I'd think this highly unlikely; it'd be too much work for the engineers to try to have two alternate systems under development within the same chip. So I expect the core operations remain unchanged and the bit depth changes because of an input/output selection, such as dts and four channel outputs, because that'd require more data bandwidth, this a reduced bit depth. However, I'm just speculating.
Hi Fellows,
Most of you have been using the 6631 or 6631A for a while I have been following this thread and I cannot pretend I understand all the techinical aspects related to these models.
If someone can recommend me a model to buy at Ebay I would appreciate it. I have my eye on this model:
eBay Australia: Buy new & used fashion, electronics & home d?r
what do you think?
Most of you have been using the 6631 or 6631A for a while I have been following this thread and I cannot pretend I understand all the techinical aspects related to these models.
If someone can recommend me a model to buy at Ebay I would appreciate it. I have my eye on this model:
eBay Australia: Buy new & used fashion, electronics & home d?r
what do you think?