low power tube amp

You need to be more specific naming the amp and speakers if you want an answer to your question that is meaningful.

i am looking at a few speakers
one is sopra 2 (rec power handling 40-300w)

Amp is built locally, class A SET, KT88, 20wpc or so

thanks

Hi klee123,
The potential problem would be driving the lower power amplifier into the range of clipping which could damage the tweeter. So it depends on how loud you listen and how hard you’re pushing amplifier.

Jperry raises pertinent questions, as there’s such variation among audio components. Two amplifiers rated at the same 20 watts can in reality be virtually night and day different as to their performance. The quality of their design, implementation, transformers and power supply could place them at polar ends of a spectrum. This is not exaggeration to simply make a point. Other than the same power rating (watts)there may be no other common ground.

If possible I’d listen to the pairing and judge based on what you hear. Depending on your listening volume and music genre you may be using just a few watts the vast majority of the time. Power is an important consideration but so is the overall  quality of the amplifier.
Charles