multi amplification and different sensitivity drivers : drawbacks ?

[mbon]

Is there any drawbacks to use drivers that have very different sensitivity in a three way active loudspeakers...?

Sample :

trebble : compression driver B&C DE25 108dB/w/m
medium : SEAS-W22EX001 87 dB/w/m
bass : Beyma 15LX60 98 dB/w/m

trebble unit require less than 1 watt to work loud
medium unit require 60 watts to reach the same trebble SPL
bass will require also 60 watts due to the needed equalization (will work sealed)

Is this a good idea to use high sensitivity trebble unit (i've heard DE25 is great, crystal clear, detailed, smooth & dynamic) ????????????????

are the first 0.5 watts of amplifier good enough ?
I've read that it was not a good idea to use different amplifier in a multi active loudspeaker design, is it true ? Why ?

[Bill Fitzpatrick]

Originally posted by mbon

I've read that it was not a good idea to use different amplifier in a multi active loudspeaker design, is it true ? Why ?

It's a good thing according to those who say even excellent amplifiers sound different. You can choose an amp that excels in bass for the woofers, etc. Even Nelson pass admits that one (or more?) of his amps has an edge in the low end.

One scenario might be; a flea powered class a for a high efficiency tweeter, a class a/b mosfet for the bass and, perhaps, a tube amp for the mids.

[mbon]

Originally posted by Bill Fitzpatrick


It's a good thing according to those who say even excellent amplifiers sound different. You can choose an amp that excels in bass for the woofers, etc. Even Nelson pass admits that one (or more?) of his amps has an edge in the low end.

One scenario might be; a flea powered class a for a high efficiency tweeter, a class a/b mosfet for the bass and, perhaps, a tube amp for the mids.

Yes but what about amplifier gain ? When pushing up the volume, every amplifier must follow with the same balance !
Is it always true ?

[Bill Fitzpatrick]

The gain problem can be solved in the electronic crossover or with pots at the amp input.

[BillFitzmaurice]

In fact, using separate amplifiers with electronic crossover is the only logical way to use drivers with sensitivities so different; otherwise you'd have to resistive pad not only the tweeter but the woofer also, which is never a good idea.