loudspeaker power handling and output capability question

[jdm56]

This is something I've always been a bit fuzzy on (among other things):

Consider a loudspeaker. Any loudspeaker will do, but just for example, and since these are the Klipsch forums, let's say a Klipsch RB-10. This speaker is rated to handle 50 watts continuous or 200 watts peak. The sensitivity is spec'd as 90 dB. Now assuming a 50 W amp, this would give a maximum output of about 107 dB continuous. But since a speaker like this is likely to be used with a powered sub, relieving it of having to reproduce any low bass, won't it's power handling ability and output capability go up as well? I'm assuming it would, but y'all know what can happen if one assumes too much.

If my assumption is correct, I think it would be nice if speaker makers offered two sets of power handling specs. One that would apply when driven full-range, and another for when the speaker is bandwidth limited due to the use of a sub.

Zat make sense?

[TBrennan]

" But since a speaker like this is likely to be used with a powered sub, relieving it of having to reproduce any low bass, won't it's power handling ability and output capability go up as well? I'm assuming it would, but y'all know what can happen if one assumes too much."

Power handling would probably go up but output might not. Note that because of compression driver output doesn't actually go up as a straight +3db for every doubling of input power. Many drivers at high power are simply acting as heat-sinks, accepting input power but giving no increase in output.

So my answer is maybe.

[jdm56]

I'll buy an honest "maybe".[]

So then, assuming no power compression, the power handling and output capability would go up. Of course at some power level, the tweeter is gonna fry. [6]

[D-MAN]

It is true that most of the power in the frequency spectrum being amplified is contained in the lower frequency portion of the spectrum. The higher one goes in frequency, the less power is needed for a given SPL (within the limits of the drivers) relatively speaking.

Reducing or preventing the output of the low frequencies from being produced by the speaker in question will lessen the power used (i.e., dissapated as heat).

So I believe the answer is YES, you will have more available power to apply to the speakers within the limits of the amplifier as that power will be distributed across the "remaining" frequency spectrum. Essentially, the amplifier is free to amplify the remaining frequency spectrum with its entire output capability.

DM

[Petrol]

so, if I'm reading you right (D-Man) while the little speakers are catching a break by not having to try to reproduce the lows, it sounds as if the amp is the one getting the most relief for it's workload....

[Hardhead]

It really depends on what the weak link in the speaker is, power-wise. It's true that the bass sucks up most of the power that a speaker uses, but IF either the tweeter or mid-range is already operating at or near its power limits without a sub, adding a sub and allowing more power to get to the tweeter and mid-range may blow either or both of them. It's worth finding out their individual limits and how close to those limits they normally operate before you give them more power.