You can add a Sub (not a bad idea with DSP3100's).
You can add Analog Sources.
You can experiment with more channels (Trifield)
Upsampling.
MRC (99.9% rooms can use MRC).
You can add more Sources than just 2.

Sorry, it's just a knee jerk reaction to me for any audio system. He can certainly add it later. He already has a preamp that handles more than 2 sources and supports analog sources. And he will be losing that. A Digital Preamp replaces that and then some.

- Fiddler (IMHO)

If you think listening to music is fun, try learning an instrument.
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