PCM4104 PCB board what do I need to complete it for a working DAC?

[Trdat]

This board is for sale at Digikey fora about 250 Euros its a 4 channel DAC board. I would like to know if all that's left is a power supply and a case to make it a workable DAC? I don't know if this is an amatuer question but as I am in the quest for an affordable mutlichannel DAC I am curious on how this fairs and if its ready to go? It seems it has a descent review on stereophile which I take with a grain of salt. Technically is there more to do on it? If so can it be DIYed or given to someone who might be able to compile it to get it working as a working DAC?

 

[Kal Rubinson]

It seems it has a descent review on stereophile which I take with a grain of salt.

Can you provide a link? I do not recall this (except for a news report from 2004).

 

[Cosmik]

This board is for sale at Digikey fora about 250 Euros its a 4 channel DAC board. I would like to know if all that's left is a power supply and a case to make it a workable DAC? I don't know if this is an amatuer question but as I am in the quest for an affordable mutlichannel DAC I am curious on how this fairs and if its ready to go? It seems it has a descent review on stereophile which I take with a grain of salt. Technically is there more to do on it? If so can it be DIYed or given to someone who might be able to compile it to get it working as a working DAC?

There has got to be an easier way, surely..? I suggest that the problem with a DIY DAC would not be so much the sound quality, but what it does when the power goes on and off - you really want to know that it isn't going to put a huge thump out to your speakers (which I have experienced).

I use this 8-channel DAC, which seems well-behaved in that regard:
https://www.asus.com/Sound-Cards/Xonar_U7/

I often leave it running for days on a Linux PC without drama.

A lot cheaper than the evaluation board you are thinking of.

 

[Trdat]

Can you provide a link? I do not recall this (except for a news report from 2004).

Hey here is a link

https://www.digikey.com.au/product-...277.666437949.1569147610-807508433.1569147610

 

[Trdat]

There has got to be an easier way, surely..? I suggest that the problem with a DIY DAC would not be so much the sound quality, but what it does when the power goes on and off - you really want to know that it isn't going to put a huge thump out to your speakers (which I have experienced).

I use this 8-channel DAC, which seems well-behaved in that regard:
https://www.asus.com/Sound-Cards/Xonar_U7/

Ah okay, so your saying its possible but by having digital crossovers if I have buzzes, thumps or anything of the sort it could possibly damage the speakers as there is any safety mechanism such as a passive crossover. Point taken, if I have understood correctly. But when you say easier way perhaps its not so easy for the amatuer DIYist?

ASUS Xonar looks good, your saying it has 8 channels but only 2 RCA at the back, I need at least 4 to power 3 or 4 different power amps? How would I go about that?

Also, its cheap and I know price is never an indication of quality but can it match a standard 200 300 dollar DAC why I ask is cause I don't want to downgrade from my NAD356 MDC DAC module?

 

[Trdat]

Can you provide a link? I do not recall this (except for a news report from 2004).

You meant this link.... And your correct its not a review its a news report...

https://www.stereophile.com/news/041904ti/index.html

 

[Kal Rubinson]

Hey here is a link
https://www.digikey.com.au/product-...277.666437949.1569147610-807508433.1569147610

Not what I asked you for. You said:

It seems it has a descent review on stereophile which I take with a grain of salt.

Is there a Stereophile review and link?

 

[somebodyelse]

According to the docs it's an 8 channel board using a pair of 4 channel DACs. While it has an spdif and toslink connector, these can only be used for stereo with left and right being sent to odd and even outputs respectively. To use it for multi-channel output you'll need to feed it from a TDM capable I2S output, say an XMOS, DSP or a board like the Beaglebone Black. You'll also need al least a +/-12V power supply. There's an all-channel mute function on a pin which may prevent thumps on power on/off.

 

[Trdat]

Somebodyelse,

Really appreciate your reply you sent me into the right direction in terms of what I needed to know. So if I go down this route, adding the power supply and the I2S output can it be a descent multichannel DAC? I know its old, but i might get away with under 500 Euros if its descent enough.

Also, when you say "these can only be used for stereo with left and right being sent to odd and even outputs respectively. I am a little confused, even initially I was confused on how do i connect a SPDIF or Toslink to either RCA or a balanced input? I presume I need a converter which will add to the cost. IF the power amp has spdif that greats but most have balanced inputs with preamps having a SPDIF input.

Lastly would I need a preamp with this or it can go straight into the power amp?

 

[Trdat]

Not what I asked you for. You said:

Is there a Stereophile review and link?

You meant this link.... And your correct its not a review its a news report... I posted above immediately when I realised its not what you wanted, you must of missed it.

Karl, do you remember if they were any good? Or any advice if I should move down this route or not?

https://www.stereophile.com/news/041904ti/index.html

Regards

 

[Krunok]

There has got to be an easier way, surely..? I suggest that the problem with a DIY DAC would not be so much the sound quality, but what it does when the power goes on and off - you really want to know that it isn't going to put a huge thump out to your speakers (which I have experienced).

I use this 8-channel DAC, which seems well-behaved in that regard:
https://www.asus.com/Sound-Cards/Xonar_U7/

I often leave it running for days on a Linux PC without drama.

A lot cheaper than the evaluation board you are thinking of.

Interesting.. I saw it showed very decent performance when Amir tested it.

How do those 8 channels work? Does it output 4 times stereo?

 

[Cosmik]

How do those 8 channels work? Does it output 4 times stereo?

They're independent, and in Linux (and I presume any other OS) you write the values to the channels you are using as a single 'frame' - not something the user generally needs to know about, but if you are writing your own software that's how the samples across channels are synchronised. So it can be configured as 4 times stereo if that is what the application needs.

 

[Krunok]

They're independent, and in Linux (and I presume any other OS) you write the values to the channels you are using as a single 'frame' - not something the user generally needs to know about, but if you are writing your own software that's how the samples across channels are synchronised. So it can be configured as 4 times stereo if that is what the application needs.

Thank you. From the info on this page I assume volume can be controlled via alsamixer?

 

[Cosmik]

Thank you. From the info on this page I assume volume can be controlled via alsamixer?

You're welcome. Yes, the channels appear each with their own slider, plus master volume (I think)

 

[somebodyelse]

Really appreciate your reply you sent me into the right direction in terms of what I needed to know. So if I go down this route, adding the power supply and the I2S output can it be a descent multichannel DAC? I know its old, but i might get away with under 500 Euros if its descent enough.

The user guide says it can achieve datasheet specs for the PCM4104 with the opamps it's using, so check the datasheet to see if you think that's good enough. Unless you're doing it this way for the fun/challenge of DIYing there are probably better options. If you're not already at least somewhat familiar with I2C, I2S, TDM and software development you'll be doing a lot of learning along the way.

Also, when you say "these can only be used for stereo with left and right being sent to odd and even outputs respectively. I am a little confused, even initially I was confused on how do i connect a SPDIF or Toslink to either RCA or a balanced input? I presume I need a converter which will add to the cost. IF the power amp has spdif that greats but most have balanced inputs with preamps having a SPDIF input.

The board has SPDIF and Toslink inputs, but they can only be used to input a stereo signal. For multichannel you need to use the I2S, and depending on the multichannel format you may have to decode it before sending it to the board. The details are in the user guide linked from the DigiKey product page.

Lastly would I need a preamp with this or it can go straight into the power amp?

It depends on how you make it. The DAC may have volume control available (I haven't checked), in which case you'd need to drive that over I2C. Otherwise you can do volume adjustment in your XMOS, DSP, Beaglebone or whatever before sending the data to the board.

 

[Krunok]

You're welcome. Yes, the channels appear each with their own slider, plus master volume (I think)

Does master volume control affect all channels?

AFAIK Volumio uses only master volume control..

 

[Kal Rubinson]

You meant this link.... And your correct its not a review its a news report... I posted above immediately when I realised its not what you wanted, you must of missed it.

No, I did see that but it ain't a review.

Karl Kal, do you remember if they were any good? Or any advice if I should move down this route or not?

I have no connection with that news report and I suspect that no one at Stereophile heard it. Just a 15-year-old news report based on press releases, imho. Why the sudden interest?

 

[Cosmik]

Does master volume control affect all channels?

AFAIK Volumio uses only master volume control..

My mistake. Just having a look at it, there are separate sliders for:
PCM Front
PCM Rear
PCM Side
PCM Centre
PCM Woofer

I don't see a master volume.

So volume control-wise it's a mixture of stereo and single channels - sorry if I misled you. An application could, however, implement a master volume by, presumably, changing the gain of them all simultaneously. And, being Linux no doubt it's possible to do anything if you know the right files to modify.

With my system, I leave all the channels set on 100% and I implement my own gain factors on each channel in software.

 

[Krunok]

My mistake. Just having a look at it, there are separate sliders for:
PCM Front
PCM Rear
PCM Side
PCM Centre
PCM Woofer

I don't see a master volume.

So volume control-wise it's a mixture of stereo and single channels - sorry if I misled you. An application could, however, implement a master volume by, presumably, changing the gain of them all simultaneously. And, being Linux no doubt it's possible to do anything if you know the right files to modify.

With my system, I leave all the channels set on 100% and I implement my own gain factors on each channel in software.

Eh, pity.. That means volume control won't work with Volumio. Anyway, thank you!

 

[Krunok]

My mistake. Just having a look at it, there are separate sliders for:
PCM Front
PCM Rear
PCM Side
PCM Centre
PCM Woofer

I don't see a master volume.

So volume control-wise it's a mixture of stereo and single channels - sorry if I misled you. An application could, however, implement a master volume by, presumably, changing the gain of them all simultaneously. And, being Linux no doubt it's possible to do anything if you know the right files to modify.

With my system, I leave all the channels set on 100% and I implement my own gain factors on each channel in software.

Btw, I would expect master volume to work in any scenario. What is your guess as to why master volume control is not shown? Does it mean driver doesn't support that function or something else?