Deleted member 48726
Exactly. Most people are somehow convinced that they don't need much power but that is only true in a desktop near field setup and with "girl & guitar" music.Others have provided links. Here is my standard answer:
For many years I have used 17 dB peak-to-average power based on an old AES article I can no longer find. Anecdotally various audio fora report 20 dB or more for movies. IME most people use much less average power than they think, but require more peak power. An online calculator can help you estimate your average power; note 80 dB is very loud to me (YMMV). Here is one:
Most people think of volume in dB and most modern AVR/AVP/etc. units list dB on the volume knob. Power in dB goes as 10log10(Power_ratio) so the change in power is 10^(dB/10). Here are some reference numbers in dB and power:
1 dB is barely noticeable and requires 1.26x the power
3 dB is what most people hear as "a little louder" and requires 2x the power
6 dB is significantly louder and requires 4x the power
10 dB sounds twice as loud and requires 10x the power
17 dB is the headroom for music and requires 50x the average power
20 dB for movies requires 100x the power
If you listen at around 1 W average, then you need 50~100 W to avoid clipping on most source material. You can figure out your estimated average power from the calculator knowing your speaker's sensitivity and distance from them. Note music may be more compressed and thus require less headroom, and the loudest sounds in movies tend to be things like gun shots and explosions where a little clipping is likely unnoticeable.
HTH - Don
I bet my left testicle (already got two kids, no big loss) that many people with speakers in room are actually clipping their amps regularly without noticing.
Seems the calculator checks out and I have just about the power I need to go deaf or burn coils. Whatever happens first.