[mshan]

Also, how good is the coaxial digital output on an absolute level vs. other sound cards and stand along high end CD players and transports?

 

[Iron_Dreamer]

I doubt that it is, because it uses RCA, whereas AFAIK true 75-ohm requires BNC.

 

[Wodgy]

Stereophile's measurements of the Digi96/8 PAD indicated that the coaxial out of that card was inferior to its optical out. It's probably best to use optical with that card.

(For galvanic isolation, it's probably best to use optical with most sound cards, but this is definitely true with the Digi96/8 PAD.)

 

[mshan]

I think I read somewhere that from a noise level the optical out was better than the coaxial.

However, I have a Scott Nixon Chibi Saru, which only has a coaxial digital output. Scott said he can put in an optical input, but that it would be inferior to the coaxial one already in there.

My Meridian 508.24 CD player has a similar, cheap appearing RCA coaxial digital output. Is true 75 Ohm spec needed for the output from your digital source, or just for the cable connect "transport" to amp?

 

[Wodgy]

Quote:

Originally Posted by mshan Scott said he can put in an optical input, but that it would be inferior to the coaxial one already in there.

That's what the general audiophile consensus is. The reasoning is that optical connections tend to have slightly higher jitter. However, that reasoning is based on a standalone transport with a clean ground. It is not so evidently true with a computer transport, when you have the switching noise of upwards of two trillion transistors to contend with on the ground. In that case, the galvanic isolation that optical provides can be helpful. This is why Stereophile's measurements showed that the coaxial output on the RME was noisier (that's digital noise, not SNR) than the optical out.

Optical is not necessarily better with computer transports, but neither is it necessarily worse, especially with glass optical. The Chibi Sauru is not all that vulnerable to jitter anyway, since it is a non-oversampling design.

Quote:

My Meridian 508.24 CD player has a similar, cheap appearing RCA coaxial digital output. Is true 75 Ohm spec needed for the output from your digital source, or just for the cable connect "transport" to amp?

For lowest jitter, a true 75 ohm connection is necessary. Many people say that in reality, RCA coaxial digital outputs are rarely true 75 ohm connections. Still, you do what you can with what you have. At least be sure to use a 75 ohm digital cable for the connection, or one that tries as much as possible to be. Some people recommend using a digital cable at least 1.5m long.

 

[mshan]

Scott Nixon told me that the Chibi Saru was more resistant to jitter than oversampling designs, but that it was also very sensitive to transport and digital cable.

Any idea why?

Also, what does the polluted ground of a computer sound card transport translate into? Increased hiss (which I can listen past) vs. other digital nasties (that may not be as easy to listen past?)?