Yes, it doesn't need as much as many people think. Of course, having a powerful amp increases your dynamic headroom (a very good thing).
The current needs would vary depending on how loud you're planning to play, and what sort of material you listen to. An amp's electrical capability is not just measured by its power rating, so it's hard to set a threshold power spec for suitability.
in addition
amplifer design comes into play here as well
wattage (watts) of the amplifer is one thing, how they are derived to get to that number is another
and we go back to electronics 101 : power (watts) = voltage (volts) x current (amps)
in as much as 100w of amp power can be permuted into several (voltage x current) configurations.
and they all sound different mind you.
Amplifiers that are more voltage over current (more volts than amps) makes the amp sound bright = great treble but at the expense of 'thinner' bass
then there are amps that are more current than voltage (more amps than volts) which makes the amp sound dark - lots of bass at the expense of thinner treble
of course the ideal is a balance between dark and bright characteristics but one factor here is:
1. who is listening?
and
2. who determines what is 'balanced'?
sound engineers 'listen' to their amplifier prototype/design extensively before an amplifier model is mass produced and/or they rehash/recycle an old design (refresh it with new parts) and incorporate it into the new model (which is often the case)
the typical japanese sound is 'clarity' - superb mids and highs, with a 'hint' of bass
the typical american sound is 'in your face' - bass and treble aplenty, so-so mids
the typical european sound is 'controlled' - open midrange, controlled bass and treble
then there are brands (inclusive of DIY) that subscribe to any one of these characteristics.
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one way out of this mess = audition with your existing gear and use your ears before you buy.
tip: take your time in auditioning. it is a tedious process I know but its worth the effort.