CM6631 usb audio interface .... any good?

Good Evening..

after burning approx 40 hours) in the board over RCA analog out to my amp i want to give you my impression -(compared to my gustard A20H):

this board is sounding well after the burn in phase, its terible until 15 aren´t left.
the sound is not squeezy and long listening is possible.the DAC ES9023P has a 2V output, so its fine to go in some line in of an amp directly...fine !

the bass is ok but somethimes in low bass its pushing to hard, for me its sound like the tone have to go out without sense to the others. :p
mid and voices are fine and at the veyr end of the high i miss some coolness. so it is not stressy but at high hats its not really clear and the board is not give enough time to swing out.
The room is 1m meter on left and right side smaller and the deepness is not gooing far back....and sideway behind the speakers:(

never the less this board cost about 27 euros so it is a fine little sounding DAC. lets hear after 100hours or more.:cool:

test over tidal (44.1khZ) - jplay - laptop- usb cable- DAC

titel -interpret-album

chilled cream - blank& jones - relax edition 4
armband - steffano Bollani - Gleda
Beat - Tingvall Trio - Beat (at CM66631A its sound strange -like L&R are changed or out of phase...i triple check the connection..... but ....no idea what here happend....:confused:?

Madrigal - Marialy Pacheco - Introducing
Don´t let me be missunderstood - Lyambiko - Saffronia special edition
Celestial Echo - Malia & Boris blank - Convergence
Movín - Gregory Porter - Liquit Spirit

chris
 
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Is it possible to buy just the CM6631 chip without a board in 10 or less quantities? I don't see it listed on Digikey or Mouser.

I'm in the process of designing a new receiver board for my setup. Right now I use the PCM2706C for USB input, but it looks like the CM6631 would allow for SPDIF input without needing a separate chip. Looking at the SDK it seems that it can be programmed to route the SPDIF in to I2S out when USB in isn't active.
 
hi Guys

what is your proposal to mod this board:

1 caps, which one and what should i choose

2 Voltage regulator is AMS1117 3.3V regulator with AP2114? which case is the correct one?

3 optical to sharp GP1FAV31RK0F
optical is not existing in at my board and i do not use optical

4 is it possible to mod the es9023P with something?


thx
chris
 
An externally hosted image should be here but it was not working when we last tested it.


It's the same dimension as Amanero :)

The UAC class is selectable and it can support following sampling rates:

UAC 2.0:

An externally hosted image should be here but it was not working when we last tested it.


UAC 1.0:

An externally hosted image should be here but it was not working when we last tested it.


The last one is supported even on Windows XP without any additional drivers.
 
Here is my version CM6631A :)

Design based on small 4 layer pcb.
On the board we have voltage regulator ADM7150 x2,
Crystek Oscillators CCHD-957 45/49MHz and isolator NVE IL715

Firmware compiled from scratch using tdtsai's SDK.

Works like a charm on linux, W7 -W10

It can play PCM up to 768kHz (in downsample/2 mode) and DSD DoP DSD64 and DSD128.

Thank You tdtsai!

I have few pcbs for this project.
 

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Here is my version CM6631A :)



Design based on small 4 layer pcb.

On the board we have voltage regulator ADM7150 x2,

Crystek Oscillators CCHD-957 45/49MHz and isolator NVE IL715



Firmware compiled from scratch using tdtsai's SDK.



Works like a charm on linux, W7 -W10



It can play PCM up to 768kHz (in downsample/2 mode) and DSD DoP DSD64 and DSD128.



Thank You tdtsai!



I have few pcbs for this project.



Bought one of this board from China but it can only transport PCM not DoP in DSD, makes it no sense, would rather to use I2S directly for flac and dsd native.

What can be wrong? Firmware? Does anybody has experience on this with dop play?
 
The UAC class is selectable and it can support following sampling rates:

UAC 2.0:

7f69f781f68f433233360d3f99e8dbf6_1523615391.jpg


UAC 1.0:

9b4398ef6bf30bac95da85129c63bdc2_1523615391.jpg


The last one is supported even on Windows XP without any additional drivers.

This is good. The first time I saw such implementation. Hope other interface designers consider such feature. I was struggling with Amanero on FreeBSD because buggy UAC2.0 implementation. I was asked Amanero developer to add support for UAC1.0, just like this board. Don't know what is the current situation anyway.
 
Here is my version CM6631A :)

Design based on small 4 layer pcb.
On the board we have voltage regulator ADM7150 x2,
Crystek Oscillators CCHD-957 45/49MHz and isolator NVE IL715

Firmware compiled from scratch using tdtsai's SDK.

Works like a charm on linux, W7 -W10

It can play PCM up to 768kHz (in downsample/2 mode) and DSD DoP DSD64 and DSD128.

Thank You tdtsai!

I have few pcbs for this project.

Is this this your PCB+firmware design from scratch? In case you did only firmware, where did you get a completed board?
 
Bought one of this board from China but it can only transport PCM not DoP in DSD, makes it no sense, would rather to use I2S directly for flac and dsd native.

What can be wrong? Firmware? Does anybody has experience on this with dop play?

I use the CM6631A to send DSD-DoP to another IC for DoP to DSD decoding. The CM6631A transfers data bit-perfect, so DoP is preserved. What are you using as DoP decoder?

Pls note the CM-6631A cannot decode DoP as opposed to XMOS which can detect DoP and decode it to DSD interface.
 
This is good. The first time I saw such implementation. Hope other interface designers consider such feature. I was struggling with Amanero on FreeBSD because buggy UAC2.0 implementation. I was asked Amanero developer to add support for UAC1.0, just like this board. Don't know what is the current situation anyway.

My Amanero isn't fully compatible with UAC 2.0 either. I believe they did fix it in newest versions though.
 
I use the CM6631A to send DSD-DoP to another IC for DoP to DSD decoding. The CM6631A transfers data bit-perfect, so DoP is preserved. What are you using as DoP decoder?

Pls note the CM-6631A cannot decode DoP as opposed to XMOS which can detect DoP and decode it to DSD interface.


The DAC chip i used on this one is ES9018K2M which is DSD capable.


USB => CM6631-A => ES9018K2M via I2S


It sounds like I am missing something in between from your post? correct?
 
The DAC chip i used on this one is ES9018K2M which is DSD capable.
USB => CM6631-A => ES9018K2M via I2S
It sounds like I am missing something in between from your post? correct?

Look at the documentation and check if the DoP is supported by ES9018K2M, in my opinion not...
See the comparision ES9018K2M and ES9038pro.
 

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I thought a month ago, but it actually does.

Had a amernero to es9028q2m also own a xmos xu208 to es9038q2m by using the same pin layout, read an article and it says 9018k2m is capable too, give that a try by hooking the cable to Xmos surprislly is does work on DoP.

Have another set of 9038 in, will try that will cm6631 to confirm, or will email to ESS to get a for sure answer