which components affect SQ most?

[RockinOut]

Quote:

Originally Posted by davy374 I was trying to get information on the quality of various digital sources. It seems like USB-I2S-DAC is the top of the line, with a debate on the merits of USB-SPDIF-DAC vs. straight SPDIF-DAC. Thanks for your help.

Yes I think that is the main issue with USB from what I've read at www.empiricalaudio.com. Good info there on I2S: Unfortunately too much moohlah for me and not flexible enough.

Another good search you can do is optical vs. USB input to DAC.

There are many threads on this.

Biggest issue with internal vs. external DAC and optical vs. USB seems to be noise.

Another option for you if you're not already familiar with it is Airport Express's optical input to DAC.

Search for IronDreamer 's posts on DAC's too he has a lot of info on different digital output methods. I've not too familiar with it, but it's there if you're interested.

Cheers.

 

[RockinOut]

One more thing regarding software, with Mac OSX, Itunes is bit-perfect unlike Window XP and the kmixer issues. You won't have to worry about setting up ASIO.

Using optical out from a Mac laptop or computer is really nice and convenient. Again don't know how it compares to other digital sources.

I really like USB with iBook or with optical via AirPort Express though. (I need to keep saying this to myself before I make an impuse MacBook Pro w/ optical out purchase, just to end up returning it due to the weird noises it makes that people are complaining about.)

Go Mac OSX.

 

[Chri5peed]

So, no one answered, is a digital-out on a good quality soundcard better than one on the onboard audio?

My sig is not what I'm using yet, the MicroDAC will be mine in 2-4 weeks!

So when it does come, I'm going to use the Optical from my Juli@ to feed my DAC, then amp it...
Is this the best way of doing it? Am I correct in assuming optical-out is a really pure, bitperfect signal? And if it is does that eradicate any need to use ASIO?

 

[thomaspf]

Quote:

Originally Posted by davy374 The difference is when those 1's and 0's come, as far as I can tell. It is the problem of jitter. I am aware of the problem, but not aware of how to fix it (i.e. which components affect SQ).

Jitter only matters in the DA converter. There are three basic strategies.

1. Master clock in the DAC. These DACs have a clock output and you need to synchronize the source to the DAC. An example would be the Universal Audio DAC with a Lynx Studio II with word clock input. Source must support word clock input.

2. Low jitter source. This works well with DACs that basically pass the jitter on the input through to the converter. Modern DACs all use receiver chips with at least one level of PLL but older design might benefit from a high quality source. An example would be an I2S output into an perpetual technology DAC. You need a low jitter source.


3. Remove jitter in the DAC. There are two basic model here. Additional synchronous reclocking or asynchronous resampling. Asynchronous resampling changes the bits in the process. Both solutions give you more or less independence from the source.

Examples would be any source with a Benchmark DAC1 (asynchronous resampler) or a Lavry DA10 (synchronous reclocking)


Cheers

Thomas