Nuforce STA200

I encourage you to leave everything on, 24 / 7, with music playing through the system. It will take, ime, a few hundred hours, for them ( the preamp, too ), for things to gel ( lean bass, as an example ). They should be better, in sq, over the Rotels, in every area, but with a new preamp, you might not attribute all of these changes to the amps themselves.......And yes, they are very quiet....Anyone who experienced them to be noisy, was experiencing the high gain of them, amplifying noise earlier on, in the signal chain. Thank you for the feedback.....Enjoy ! MrD.

Has anyone used this amp with JBL Studio 530 speakers (86 dB, 6 ohms) ?

Ooh, I'd like to know this as well.  I love the 530s

I bought a STA200 and have about 5 hours of listening into it. Using on 86db/6ohm speakers and coming from a well respected chip amp. First thing I noticed was the impact this amp has at higher volumes.Very dynamic and lively -  it is meant to be played loud!  However, highs are a bit strident / grainy and bass/mid-bass is a little too exaggerated and loose (on my speakers).  I have a feeling the 60hz-200hz range is somehow accentuated on this amp.  These faults are easily overlooked when the volume turns up and you start "feeling" the music. It's dynamics & speed are addictive.  I wonder how much improvement could be had with a 2nd unit in a vertical bi-amp set-up...my rational self thinks it may not be worth it for a 10% subjective improvement in performance.  I will continue to listen for improvement as the amp breaks in.

A couple hundred hours for break in. Leave it on, continuously, with music playing through it, if possible. The question of vertical bi-amp....I feel it is significant, but this goes with many dual amps I have had experience with. As far as a purchase, making any percentage of improvement, well, this is all part of our industry. It is a great amp, at the selling price, for many systems, and not the best, for others. System matching is still very important.