In article .com,
wrote:
I have an 80 wpc amp and am thinking of replacing my speakers.

The critical questions here would be:

1) What is the reason for wanting to replace your current speakers?

2) Can you get the sound levels you require with your current speakers, and
what is their nominal sensitivity?

If they play loud enough for you, then other speakers with similar
sensitivity and power handling should be fine. If they won't go loud
enough, then you may need either higher sensitivity, or/and more power.
Note, though that a change of 3dB won't sound like very much. You'd
probably need 10dB or more to make a dramatic difference.

I had read that sensitivity is often compromised in higher end speakers
because higher end amps are often high wpc so can still drive them.

Sensitivity tends to be involved in the trade-off between physical size and
bass extension. Although an expensive design might have a nasty input
impedance on the assumption that an expensive amp can handle this, there is
the risk that the owner won't do as expected. :-)

Although this sounds plausable I've also read that valve amps are ofter
low wpc. Besides dont amps prefer less work so they have more power in
reserve for fast transients?

An amplifier will have a given ability to drive continuous levels, and a
given level to provide peaks. They have no 'preferences' as such. Most
music in my experience has peak/mean ratios of 10dB or more, which means
the continuous parts won't drop the peak level available much if the amp
has a decent PSU. (If it doesn't, don't buy it. :-) ) This said, given the
compression and clipping on some pop CDs. However if pop CDs are your main
music, then this might be a problem which could occur, but may not matter
much given the clipping already on the CD. :-/

The usual amplifier ratings will be for continuous use, and the chances are
that the peak levels will only be a couple of dB greater, which in
listening terms isn't very much. If 80Wpc isn't enough for you, then you'd
probably have to move to the order of 200Wpc or more to make a marked
difference. (Unless your amp has problems with something like current
limiting.)

FWIW In my experience in the UK most people with 'powerful' amps only
actually use them to output modest power levels. Although this will depend
on your taste in music and the size of your listening room. :-)

Slainte,

Jim

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