I bought some old speakers (JVC S-55) with a "power handling capacity" of 40w RMS, but it also says 80w Music. Does anyone have an idea of what that could mean, and which one do av have take into concideration when buying an amp?
The 80W music is the much hated PMPO rating (Peak Music Power Output) and the other measurement is RMS (Root Mean Square) The PMPO is meant to be the maximum 'music power' of the speaker, which is rubbish, as the speaker would not last very long if it were run on that. It is also a marketing con, as the higher the figure you put on a speaker, the more attractive it becomes. RMS, is the true voltage power rating of the speaker in real terms. Much like an electric heater would have printed on it. Always go on the lower one of the two to get your speaker rating (RMS)
Unfortunately for you, vendors don't advertise these things for you to make an informed decision.
Fortunately though, from people who's done this for a long time, this doesn't need to be that precise. ANY amp that is rated 50-100w per channel would be fine. That this means what any rating over 100w no good? of course not, just don't turn it up all the way, which in a home environment, I assume, nobody does "turn it up all the way." Don't over-think this.
The 80W music is the much hated PMPO rating (Peak Music Power Output) and the other measurement is RMS (Root Mean Square) The PMPO is meant to be the maximum 'music power' of the speaker, which is rubbish, as the speaker would not last very long if it were run on that. It is also a marketing con, as the higher the figure you put on a speaker, the more attractive it becomes. RMS, is the true voltage power rating of the speaker in real terms. Much like an electric heater would have printed on it. Always go on the lower one of the two to get your speaker rating (RMS)