Per Alan Shaw:
Harbeth speakers will work with any normal grade, audiophile or regular grade amplifier that is performing within its original specification. They will work better with a really good amp, but they will work well with even a modest hi-fi receiver-amplifier. Remember - amplifiers like people age, if it breaks-down it could damage the speakers.
Harbeths present an easy electrical load to their driving amplifiers. They are deliberately designed to be so. There are tens of thousands of Harbeth speakers in use around the world and we do not have enough knowledge or staff to handle inevitable questions such as 'will Harbeths work with XYZ amplifier?'. So, we have always made absolutely certain at the design stage that Harbeths will work will any credible amplifier. You do not need to ask this question, because the answer is, if the amp is working properly, that yes, it will work with your Harbeths. More on amplifier selection here.
This question (or as I say, non-question) about speaker-amp matching does arise from time to time. I try to explain our position; here again is a summary.
Harbeth speakers do not need big amplifiers. Generally speaking, 25W per channel is a sensible minimum across the range. That will get you going but 25W won't produce the maximum loudness that a Harbeth is capable of: for that you'll need a bigger amp. If you play soft, late at night or you don't want to annoy your neighbours then a few watts will be enough power. What if you have a really powerful amplifier? A bigger amp, like a bigger car engine, will give you a power reserve which you may or may not ever need depending on your music listening habits. Obviously, if your children take control of your hi-fi then a more powerful amplifier could/may/will do more damage just as a powerful car driven too fast can/may/will. In brief: use whatever power you have responsibly.
Harbeth speakers will work with any type of amp: solid state (transistor, MOSFET) amps, digital amps or tube (valve) amps.
