Soundcards

Just out of curiosity has anyone ever built a DIY computer soundcard? Newer ones really don't have much on them, mostly it just revolves around one chip. So it must be doable, and if it is someone must of done it...

I've found some plans for something for the National LM5449, although it's chinese and doesn't seem to be geared towards DIY...
 
Oh, I see. Well, I can always try. My idea so far is that the AC97 way would probably be the easiest to accomplish, and for the analog component the LM4549 looks alright (fairly new, and I like national). Have any ideas for the digital component of the AC97 architecture?

As for PCI, I know it's rather cumbersome (sp?), so I was actually thinking of AMR. I haven't checked into the AMR specs yet, but it must be better then PCI... And since the linux AC97 drivers are open source, if I don't adhere to the standards, it shouldn't be hard to write a custom driver.

The soundcard is all I'm missing now for my complete DIY stereo system...
 
use USB

You could always use a USB interface instead of PCI.

Micronas and Phillips make USB Audio IC's. The Micronas includes built-in A/D and D/A, as well as a headphone amp, though I suppose you would probably want to use I2S to interface with a higher-quality DAC.

Of course, this would all have to go in an external box with it's own power supply, but that would eliminate all that RF inside a PC case.

There's probably a lot more to it as well, I just started looking at this idea a couple weeks ago, and haven't spent a lot of time on it yet.
 
AMR is actually a design spec and was never meant to actually be used :) just like CMR it is 100% dependant on the host CPU so expect the machine to run like mud if you use it.

Now USB on the other hand would be doable but unless you want to write you own WDM driver you'd have to build it to be compatable with a solution that is already available.....
 
Thanks, I found the micronas one but not the philips before. Looks interesting, though I don't know if it'd be easier to implement then a PCI version... Philips has a whole range of them I see, while micronas had it all in one package so to say...

Also did you take a look at the UDA1335 and UDA1325 (although the UDA1335 seems to be discontinued)?
 
Well, I'm up to a challenge, after all I have contacts with people who build soundcards for a living (ever hear of mediatrix?), so I could always get help. I agree that the micronas chip would be the way to go, but I can't find a place to purchase micronas chips in single units. I've been looking for a place to purchase a micronas MAS3507D and a DAC3550A without any luck for a little while now...

Also, I was looking at the micronas UAC355xB, haven't looked at the UAC3552A yet...
 
Well, this idea is something I'd like to eventually do, I'll probably talk to a professional on it this summer. But for now if I wanted better soundcard sound I was thinking of just modding my current soundcard. For the situation it's being used the soundcard has to be a SB16. But I noticed that it used a TDA1517P which is a 6W per channel 2-channel class-b amplifier. Now, I don't want my sound to be amplified since it's going to my pre-amp right after the soundcard. This amplifier is for non-active computer speakers, correct? So removing it and bypassing it should work out fine, correct again?
 
AudioFreak said:
also you'll find that the quality of the sound output from a sound card is inherently limited by high frequency noise present inside a computer.... the answer? you use the sound card to output a balanced digital signal then you do the processing outside the computer case.

Indeed. There are a few other options Creative Labs have come up with you guys might be interested:

- SB Extigy - external USB sound, nice looking and presumably as good quality as the Audigy.

- SB Live/Audigy S/PDIF coaxial output. Platinum eX version has the Audigy Drive in a format that can be connected externally via 2m cable. You can also buy a 3rd party adapter that will provide optical output for as little as $20

- SB Live Drive / Audigy Drive Optical output. They're expensive for what they are, though.

- Wrapping your sound card in insulated metal foil. It works fairly well, I've done it.
 
JoeBob, I just had an idea. Check this out:

If you are really interested in a PCI based solution, there is an alternative that can get you there without all of the pain and suffering of a custom PCI layout. See if you can get a hold of a PCI prototyping board. I can't think of any sources offhand that I know has them, but some of the programmable vendors like Altera and Xilinx may be a good start. Or, you could just do a search on Google for "pci prototyping board" and see what you get.

Ideally, you can find one with a dedicated PCI to xxx interface chip already there, to which you can attach the audio controller of your choice. You will have to figure out a way to add the DACs, since I think it would be quite hard to find a board with ones already designed in.

I'd be interested to see what you can find.