Head-Fi.org › Forums › Misc.-Category Forums › DIY (Do-It-Yourself) Discussions › USB to TOSLINK/SPDIF converter
New Posts  All Forums:Forum Nav:

USB to TOSLINK/SPDIF converter

post #1 of 11
Thread Starter 
Problem statement - how to deliver bit-perfect KS/ASIO from Compaq 6910p notebook to Entech Number Cruncher DAC.

1) My notebook doesn't have digital out, only USB, and I'm not even sure if I can transfer non-oversampled, bit-perfect redbook thru it ...but that's step one

2)How to apply the least amount of conversion to that redbook so to feed ENC DAC thru TOSLink (optical or coax). The DAC doesn't want to swallow anything above 20 (i.e. 16) bit and 44.1KHz, and so balks at the typical 48KHz output from most "el cheapo" digital outs

I really don't want to give up on the DAC as I like it very much (it's modded , no caps, low DC offset etc.) I'm willing to accept another DYI DAC as long as there are no capacitors on the signal path (pls don't try to convince me on that).

Your advice is much appreciated.

Thanks!
post #2 of 11
The gamma1 dac ( The γ1 Modular Miniature DAC ) can be configured as a usb->spdif converter. On the software side, I use Foobar2k with the ASIO plugin to get bit perfect audio and I'm pretty sure you can change settings with either foobar or ASIO to get 16bit 44.1khz output.
post #3 of 11
post #4 of 11
Thread Starter 
Thanks guys, but considering I'm not interested in anything above redbook fidelity is there "a plain and simple" solution along the lines of buffer-clock-decoder/encoder which can be DIY'ed for a day and cost less than a $100.

I guess I'm asking for too much ...
post #5 of 11
The gamma1 as USB to SPDIF build meets your requirements exactly.

An example build is here
post #6 of 11
Also, twisted pear has a USB reciever: The USB DAC/Receiver

You can buy it premade or buy the board and parts and same a fair bit of money.
post #7 of 11
Perhaps it would be better to buy a uDAC than to shed out money for a converter.
post #8 of 11
turtle beach micro advantage. usb to opto/spdif dongle for $35 or so.

then into your dac.

easy as pie
post #9 of 11
Thread Starter 
Nope, TBAAM won't work. That's what I have now - it can't keep redbook pristine, it resamples to 48KHz. I went through a lot of pains to get my DAC bias in check without having any caps in the signal path, and I want to keep the DAC, but it won't process 48KHz

I'll get one of the $25 dongles off eBoy and see how bad these are. I still have to convince my ears that USB->SPDIF conversion makes any difference ... as long as the signal is not venturing through DACs, ADCs and whatnot that is.
post #10 of 11
Quote:
Originally Posted by Xakepa View Post
Nope, TBAAM won't work. That's what I have now - it can't keep redbook pristine, it resamples to 48KHz.
sorry, but that's not correct. I have one and I've proven it does 44.1 output just fine. I have a device that displays (directly) the bitrate and it clearly comes out as 44.1 on my cd's and mp3's. if you get 48k, its your software and not the dongle, I'm sure of that.

here's the dongle, taken apart:



(mine.)

its the cmedia chipset, clearly. and that is known to be bit-perfect.



Quote:
I went through a lot of pains to get my DAC bias in check without having any caps in the signal path, and I want to keep the DAC, but it won't process 48KHz
I could comment on the 'caps' issue but I won't. lets stick to digital for now

I would suggest booting a live linux cd and doing a test with that. it should see the dongle just fine (cmedia chipset) and if you have a home theater 'avr' receiver it should also show bitrate on its display, somehow, if you send spdif to it. try playing a cd or .wav or .flac file using the linux live cd (just copy a .wav sample to a usb thumb drive for a test). you'll see it come out as 44.1. in fact, you'd have to do extra work to have it come out *resampled* at 48k if you are using linux
post #11 of 11
Thread Starter 
Problem solved, and the credits go to Linuxworks. Thanks a lot. Head-Fi works.

I'm not sure what was I doing wrong, but the DAC somehow wasn't locking to the TBAAM. Following your post I tried that again and wow it worked!

Windows XP, FB KS to TBAAM @ 16-bit, no DSPs - and the DAC locked right out
New Posts  All Forums:Forum Nav:
  Return Home
Head-Fi.org › Forums › Misc.-Category Forums › DIY (Do-It-Yourself) Discussions › USB to TOSLINK/SPDIF converter