More Power is always good?

Keep in mind that the speakers totally dictate the needed power and type of amp for good synergy. First the room size and volume level you like to listen to have to be taken into acocunt. With the grand piano's , 30 tube watts(correct impedance of course) would be fine- bass quality has many factors involved for high quality but overall power is the least of those factors. Damping factor, room acoustics, room placement and on and on. Never buy into more power is better. Most lower power amps from the same company sound better (don't believe that-check out wavelength audio). Try to stay as low as you can with quality being more important than quantity. Current is the important factor as far as actual power is concerned. The current abality is far more important than the watts rating. More efficient speakers with smooth impedances require much less power than low efficient and wide impedance speakers. So there is no telling what amp to go with if you are changing speakers- no way to tell till you get them.

Mahandave is right.

Watts that are composed of higher amperage are stronger watts.

Efficency of speaker dictates how loud it will get with a given number of watts.

Speaker placement/room dimensions will dictate (more so than most other factors) how tight or accurate the bass response will be.

Find a pair of speakers that are capable of doing what you want them to do in your room. Build the rest of the system around them. Audition at home before you buy.

Good luck!

Bass quality can easily be compromised due to lack of power. This is where a low powered amp will show clipping first. It's best to have an amp that has enough power that it nearly never or never clips. I've seen a number of times where what you describe was no more than a lack of power. At normal listening levels you only use a couple watts or so but when a strong bass line comes in that's when your amp can go into clipping and it's easily audible. The power draw during these periods can need 100 times the power of your average listening needs from your amp. I use a 300wpc amp in my 12x17 room with 90db sensitive speakers and feels it's adequate. With A 100wpc amp I'd be clipping for sure.

When you double the output power you only gain 3db which is a bit more than noticeable. So you'd probably want to go to at least 100wpc if you're struggling with 30.

Almost all the time a good SS amp will have better bass than a tube amp. The damping factor of tube amps is typically very low in comparison and it's quite audible.

if that were the case people would not spend $30,000 for 3 watt amps...