Bel Canto DAC3 without preamp

You're not losing at all, IMHO, but doing this. I am doing the same with Bel Canto DAC3 into Bel Canto REF1000 MkII monoblocks. I lost absolutely nothing (except additional gain, if it was ever required) from when I used to have a Bel Canto PRe2 in my system which was an excellent, dead neutral sounding preamp. You'll notice that at pretty much all the shows over the last couple of years that the Bel Canto room always has the DAC3 going directly into monoblocks rather than using their PRe3 in the chain. John Stronczer feels this is sonically their best solution if you aren't using an analogue source.

I was running a dac3 into a s300 for a while and didn't really have any complaints, very neutral overall, tight bass. Then I got a Jolida 502brc, and in comparison, the dac3 to s300 sounded very flat and lifeless, and not as open,or detailed, but it may sound great in your system? Take the preamp out of the chain, if you think it sounds great, leave it out.

First I think if you put a pre into your system it needs to be a good one. I put a Aesthetix's calypso pre into my system which I thought improved the music. It became more natural and full sounding more like live music. If I did lose any detail i did not notice it. Try it and see what you think. I would suggest trying some tube pre's. There is lot's of previous discussion on this topic.