upgrade DAC/Amp for Peachtree Decco65?

What speakers are you using, and what's the room like?

I'm a Peachtree user - I have both the Grand Integrated X-1 in one system, and a Dac-itX in another (with the same 923 DAC chip that you have) - so I know what they sound like. If you're looking for more detail, or transparency, etc. I'm inclined to look at your speakers & room before trying to upgrade the amp & dac in the same price range.

I'm a big fan of the Grant Integrated X-1, it allowed me to build a really sweet system with very few components...computer to Grand X-1 to speakers, nothing else needed. It has tons of power, I like the Sabre dac, and the X-1 is built like an army tank. Best of all, Peachtree's USB implementation in the X-1 is really well done - I get nice sound out of the USB connection.

My room is a lot like yours, very small, 10x11, so we're dealing with similar challenges.

Your ELS3 are fine speakers from what I've read, though I've never had the pleasure to listen to them. Honestly, in a room as small as yours the real obstacle is speaker placement and taming reflections. Not that you shouldn't strive for whatever transparency you hope to get, but chasing it via an amp upgrade in your price range may not yield worthwhile results. Do you love your speakers? If not, I can imagine finding something on the used market for $500-800 that may prove an upgrade. My personal strategy has always been to focus on the speakers first - make sure you love those before looking at anything else.

It's hard to make recommendations because I have never heard those EPOS speakers so I don't know, with my own ears, what they do well and what they lack.

There's been a lot of positive talk about new speakers from Elac, the Debut line, designed by Andrew Jones. They'll be in your price range, and there seems to be a lot of excitement about them. I think they're due later this year - definitely worth some homework.