Minimum amplifier power question

[Honda Z50M]

As per title some speakers state a minimum amplifier power of say 50W for example what does this actually mean?

For instance if I used a 25W amp on such a speeker what issues would I come across?

Regards
Tom

[nigelwright7557]

I have never seen a minimum power for a speaker.
Its usually the maximum rated power they state.

Putting a 25W amp on a 50W speaker is not a problem.
It obviously wont be as loud as a 50w amp on a 50w speaker.

My preference is for my speakers to easily take the power from my amplifier without any chance of frying them.

[chris661]

I'd ignore any "minimum amplifier power requirement". Most of the time, you'll run at less than a watt, assuming the speakers are reasonably efficient.

You won't run into any problems running 25w a side, unless, of course, you clip the amplifier.

Which speakers are you looking at?

[Honda Z50M]

I have a modified Cambridge A1 amp and am lookong at a pair of B&W DM2000's, was just reading info from B&W which states minimum amplifier power 50W.

Tom

[Charles Darwin]

Minimum amp power recommendations are usually there to avoid the amp clipping in normal(ish) listening conditions.
Personally I like to use amps capable of twice the output of the maximum(!) amp power recommended by the speaker manufacturer.
The Tannoys I use are capable of taking 125w and Tannoy recommended amps between 125 and 300w in the tech manual.
Bear in mind that if you listen at 90dBspl average that there will be peaks of 102dBspl or even more (depending on the music you listen to) and the amp should be capable of producing the required power cleanly.
Most tweeters die due to to small an amp that is clipping during loud passages.

[nigelwright7557]

Originally Posted by Charles Darwin

Minimum amp power recommendations are usually there to avoid the amp clipping in normal(ish) listening conditions.

That probably works ok in the home.

In a disco or band situation the guys will always want it louder so they will turn up the amp to full throttle. So a high power amp on lesser powered speakers will fry every time.

I worked for an audio company for a while and i was permanently kept busy replacing fried speakers and tweeters.

[Charles Darwin]

A company I worked for rented part of their warehouse to a PA hire company.
They used amps capable of twice the power of what the drivers would take. That was very reliable but then their gigs were large enough that none of the musicians would ever get close to an amp rack or would even want to.
Can't trust DJs though as they tend to overdrive their little mixers and once the waveform is clipped it is just a matter of time before the tweeter fries.

[Honda Z50M]

Originally Posted by Charles Darwin

Minimum amp power recommendations are usually there to avoid the amp clipping in normal(ish) listening conditions.
Personally I like to use amps capable of twice the output of the maximum(!) amp power recommended by the speaker manufacturer.
The Tannoys I use are capable of taking 125w and Tannoy recommended amps between 125 and 300w in the tech manual.
Bear in mind that if you listen at 90dBspl average that there will be peaks of 102dBspl or even more (depending on the music you listen to) and the amp should be capable of producing the required power cleanly.
Most tweeters die due to to small an amp that is clipping during loud passages.

What is "Clipping" the DM2000's have built in protection circuit that limits maximum power regardless of input power.

[Mooly]

Have a read here and the link in the post below it,
MJR-7 Mosfet Amplifier of M. Renardson

[Honda Z50M]

Just looked up clipping on Wiki, when load noises get cut ogg as amp reaches the limit and until the point where load and low noises are same volume as they are all at same cut of point.

BJUT that said I won't be rattleing the windows, at moment I very rarely use the amp near 25%, normally about 10-15%.

Tom