Help? good & cheap SPDIF out for PC

[net-david]

Help? good & cheap SPDIF out for PC

Hello all,

I have been reading this forum with great interest, and hope you can help me.

I am looking for a good and cheap SPDIF out for my PC to drive an external DAC. I don't really want to buy a $500 pro sound card just to get a quality SPDIF output. I am currently using the SPDIF out on my Asus P4C800 mobo, it uses the AD1985 chip. Is this good enough? Would a pulse transformer or some other signal conditioning help? What about the posibility of using the PCM2902 just for the digital out?

Just for reference, I am using a Channel Islands Audio VDA-1 DAC (DIR1701/PCM1716/OPA2134) to a Jolida JD 1501 amp to Monitor Audio Silver S1 speakers and REL Q150E sub.

Thanks,
David

 

[jwb]

The S/PDIF output on the AD1985 comes directly from the AC '97 interface. Unlike the output on Creative Labs' products, it is not resampled. I think it should be fine for your purpose.

By the way, I have the same motherboard. Did you know that ASUS have physically wired the Surround/Headphone output to the line out jack, and the Line Out output to the line in jack? Very weird. I had to modify the ALSA driver for Linux to make it work backwards.

 

[net-david]

Thanks!

Thanks for the reply JWB. I was hoping it was good enough, I like the "cleanness" of having everything on the motherboard, not having to use an add in card.

I have not run into the problem you described re: the jack wiring, I have never tried the analog I/O, always just used the SPDIF. Thanks for the heads up, I wonder if this is isolated to Linux, I am enslaved to Bill G. (WinXP Pro)

By the way, I have been looking at your DAC schematics, I am interested in making a stand alone CS8420 SRC.

David

 

[jwb]

Yeah I like having things on the mainboard as well. The P4P800 allowed me to throw out my NIC, sounds and FireWire PCI cards.

The AD1985 is just weird. The high-power amp is on the surround output, so you practically have to use it as the main output. The problem is just that the attenuator for that output announces itself as "Surround". So if you internally route the main DAC to the headphone amp, and this goes through the Surround mixer, and is wired to the Line Out jack, the situation is thouroughly confusing



Cheers.

 

[lenz]

hallolenz@web.de

@net-david
I can send you a diy-instruction to build an external soundcard
needing on the USB-slot.
Or an instruction for a very small and cheap direct USB-Audio-DAC.It`s so good,that you can forget your present external DAC.

Lenz

 

[bigparsnip]

Hi, I would be interestd in knowing about the direct USB DAC. Would you be able to send me the information, and are there drivers available to amke it work in widows?

 

[net-david]

USB-SPDIF

Lenz,

I would like to see your designs.

I have been looking at the PCM2702 for USB to audio and the PCM2902 for just the SPDIF out, but these just do 16/48. I have not been able to find a USB to 24/96 SPDIF chip except for a little info from C-Media on the CM-101S. There must be others out there since m-audio makes the Sonica and the Sonica Theater, Audiotrak makes the OPTOPlay, etc.


Thanks,
David