[Skan]

So I just got this amp, was labeled as a DAC... from what I was reading I thought a DAC always had a usb port so it was able to hook up to your computer.  The back of this amp has a coaxial cable optical, R and L..  Is there any way to hook this up to my computer with a cable and not buy another DAC?
 
 

 
Ok, so I've done some looking on internet and I have narrowed it down to two possibilities
 
http://cgi.ebay.com/NG-OPTICAL-USB-SPDIF-Optical-Audio-Converter-/280581954912?pt=LH_DefaultDomain_0&hash=item4153fcdd60
 
and http://cgi.ebay.com/NEW-USB-SPDIF-OPTICAL-HI-FI-Adapter-/120576182185?pt=LH_DefaultDomain_0&hash=item1c12e687a9
 
any suggestions on which would be better?

 

[Avro_Arrow]

While I have no experience with either one of the adapters you mentioned, both look
like they should work. Remember too the USB can only output at 16 bit/ 44.1kHz.
Remember for next time, not all DACs have coax/optical/usb inputs. Check to
see which ones are supported.
Not all computers only have USB out, mine has Coax out...you might want to
look for this in your next computer or sound card.

 

[Observer]

Quote:

Remember too the USB can only output at 16 bit/ 44.1kHz.

Avro_Arrow
Are you sure about this?  As a newb myself, doing reading (on head-fil) and learning on other sites, it appears USB can support UP to 24/192k for USB 2.0 (Class 2).  Furthermore, the "low end" side USB 1.x (Class 1) appears to support UP to 24/96k.
 
Source: http://thewelltemperedcomputer.com/KB/USB.html
 
For the OP:
The need to go "higher" than 24/96k is quite a hotly debated topic.  For this, I have been closely observing the thread which Dan Lavry has been generous enough to weigh in, and his whitepapers, albeit can be a bit technical, but if you have a technical background, it makes a lot of sense.  As a VERY simplistic summary of the thread (based upon my opinion only) is that pushing past 24/96k is the point of diminishing returns, and results in a non-audible gain, at the expense of much more processing requirement and storage requirement, which directly contribute to additional financial cost.  Again, I emphasize, this is MY OPINION only, as I'm not interested in turning this thread into a debate.
 
 

 

[FallenAngel]

DAC : Digital to Analog Converter... there are multiple digital formats, such as USB Audio 1.1, S/PDIF, AES/EBU and I2S to name a few.
 
USB 1.1 is rated for 12mbps, more than enough bandwidth to carry stereo 24/96 content, you just need drivers that handle it.  As most computers now use USB 2.0 at 480mbps, you can easily transfer multiple 24/192 channels, depending on drivers of course.
 
As for those 2 USB to S/PDIF converters, I haven't used either one, so I can't say.  I did use the first one but with a coax output, and it did it's job as expected.

 

[Avro_Arrow]

The information I could find from the USB DAC data sheets was the they support up to 16 bits at 48k in PCM format.
In MPEG format I found that USB support much higher rates, at least 24/192 but could not find what the standard
for PCM was. Other information I found from several DAC manufactures talked about "upsampling" the USB data
 to 24/196 which means to me that is started out at a lower rate.
 
Maybe someone more familiar with USB audio standards can chime in and point us to the right answer...
 
Quote:

Avro_Arrow
Are you sure about this?  As a newb myself, doing reading (on head-fil) and learning on other sites, it appears USB can support UP to 24/192k for USB 2.0 (Class 2).  Furthermore, the "low end" side USB 1.x (Class 1) appears to support UP to 24/96k.
 
Source: http://thewelltemperedcomputer.com/KB/USB.html
 
For the OP:
The need to go "higher" than 24/96k is quite a hotly debated topic.  For this, I have been closely observing the thread which Dan Lavry has been generous enough to weigh in, and his whitepapers, albeit can be a bit technical, but if you have a technical background, it makes a lot of sense.  As a VERY simplistic summary of the thread (based upon my opinion only) is that pushing past 24/96k is the point of diminishing returns, and results in a non-audible gain, at the expense of much more processing requirement and storage requirement, which directly contribute to additional financial cost.  Again, I emphasize, this is MY OPINION only, as I'm not interested in turning this thread into a debate.
 
 

 

[Avro_Arrow]

I read the article mention above and it seams I am both right and wrong.
It's not the standards that limit USB to lower rates, it that the chip most
often used is the limiting factor.
So my warning still stands...unless the converter uses something other than
the PCM2906 to convert the USB to SP/DIF then it is limited to 16/48.

 

[Avro_Arrow]

PCM270x also offer SP/DIF out at the same rates as PCM2906...