Where does the DAC go?

The digital output on any device, whether it is a CD player, DVD player or computer audio device like the Roku is all the same. It is usually Toslink optical or S/PDIF coaxial or both. This is a single cable that multiplexes the left and right channels in digital format onto one cable. The DAC takes this as input and generates left and right analog signals, two cables. This is generally fed to a preamp, integrated amp or "receiver". Sometimes the preamp is in the DAC, so it can drive amplifiers directly.

It is best to avoid use of digital volume control. This will reduce resolution and detail. Use analog volume instead with a preamp or passive transformer linestage like the Music First. Also avoid resistive passive linestages. They can give more detail, but dynamics usually suffer.

Steve N.
Empirical Audio

System: Cary Audio Design SLI-80 cranked up to F1 specs (and more) by/at the factory running Genalex Gold Lion KT88s, NOS Tung Sols and RCAs for preamps, AP Virgo IIIs, all custom solid silver ICs and speaker cables, Tice power conditioner; analog end is VPI Signature Scoutmaster and Benz Glider S lo output, Phonomena phone pre, couple of Shunyata power cords in there somewhere...

What streams? Like, MP3, AAC, WMA?

I kinda knew going in that this ROKU may be a little bit, um, underwhelming vis-a-vis the rest of the rig, but for $100 i figured it would be a start

A system like yours would certainly benefit from a better DAC than the Roku, IMHO.

I think you might be asking what file convention to rip your files in, which is certainly a good question. The answer is highly debatable, but I tend to prefer the lossless options which include WAV (I'd avoid this for type for the lack of metadata support - trust me on this one), AIFF, Apple Lossless, FLAC. I believe the three you suggested are all compressed file types (someone correct me if I'm wrong). You should also be selective about the software you use to rip those files (I'd avoid itunes and go with something like MAX for Macintosh, and there are many choices for PC like EAC or MediaMonkey - not much experience with PC's myself)

I thought the ROKU was marketed primarily to stream video, and did not have as well implemented an audio/digital section as something like the Squeezebox Touch. The latter has pretty decent jitter specs on the digital out. I'm not familiar enough with the ROKU to really comment beyond speculation so I'll leave it to others.

Oh, if you are just using it to listen to low-res internet radio streams then my comments do not really apply. I don't know how much you'd gain by a better DAC in that case as I have no direct experience to share. I don't listen to Internet radio enough to have an opinion one way or the other.

Exactly. Low bit-rate streaming has limited resolution and you may not get any improvement for your DAC investment.

Set everything up and use it for a while. Then, get hold of a good DAC that has a 30day return and try it. decide for yourself.

Kal