I have always had my computer sound coming from the built in monitor speakers. New monitor with no speakers so now I need a set of speakers. Since I have a spare pair of bookshelves I'm thinking of just hooking a 2 ch amp to my sound card and using the bookshelves. Does anyone know of a very reasonable 2 channel home amp that accepts optical input? And does this set up make sense over just buying computer speakers?
You don't need a separate DAC. I had the Xonar D1 before upgrading to the Xonar Essence ST/STX series. The D1 has excellent SQ that will produce good analog output. I found it to be as good as the DAC output in low entry level AV receivers when I did A/B switching between the analog from the D1 and the optical. There are enough good reviews online of the D1 and DX (the PCI version) to confirm this.
Meanwhile, since you didn't mention budget, here's a more expensive amp. Emotiva makes a nice 50 watt amplifier. Use TAKE10 as a discount code for 10% off (see the ad on their home page).