Panerai,
We have to note a point with Dupac's comments, the Bryston 4B3 does he mean the SST3 series, is a very different amplifier than the newer cubed series.
Personally after being a Bryston dealer for a few years we found the Bryston amplifiers when paired with a tube preamp was the magic ticket.
Personaly we would agree that the Pass should be an even better sounding amplifier than the Byston which still sound a bit cooler to our ears than some of the other really great solid state amplifiers.
We would also strongly recommend that you also consider a Coda .8 which is a steal for the money, power rating is 150 watts with the first 18 being Pure Class A. The Coda was compared to a set of the way more expensive Pass X60.8 and found to compete very favorably with them.
Coda is from Doug Dale who was the senior engineer of Threshold with Nelson Pass. Pass left to form Pass Labs, Dale left and founded Coda.
Coda is not as well known but has a cult following for their remakable sound quality and price which tends to be lower than Pass for a very comparable amplifier.
The new .8 series uses a massive 4k transformer coupled with a brand new output device this amplifier is rather remarkable, fast, smooth, and powerful.
One of the world's best amplifiers and very affordable.
As per power 20 or 30 watts will be more than enough with even an inefficient loudspeaker, you are close to the speaker and don't play that loud
Good luck on your search.
Dave and Troy
Audio Doctor NJ