way to increase driver sensativity.

[mp006ltk]

I have a pair of woofers that are 90db each so in parralell they should wind up being 93 db
I have a tweeter that is 93 db
and I have a midwoofer that is 88. are there any ways to use the crossover to increase the sensativity of the midwoofer to match rather then bringing down the tweeter and woofers to match?
Can I increase the driver overlap? make the bandpass sloped more steep?

Thanks in advance

[rcavictim]

You could horn load that midwoofer. Doing so will make you unhappy with the rest of the system and lead you on a fun and challenging path that can end up with you being in audio heaven.

[454Casull]

If you tri-amp, you can set the volume on the midwoofer amp higher than for the other two amps. I wouldn't recommend it, though.

[mp006ltk]

in this case I can't do either of the above, but they were good advice and apreciated. I am cloning a watt puppy to an extent I haven't yet seen from others who have done it. When done it will be hard to tell them apart. I know that wilson can order special drivers or modify them themseves, but I'm hoping that short of removing the voice coil and rewinding it to my needs that there is an easier way. I have substituted the tdx tweeter with teh td5 and the dynaudio woofers with peerless hds series units. I have welded flanges on to the truncated baskets to make them appear to be the dynaudio drivers. All mi woodwork is absolutely precision, and my drawing was done from measureing an actual watt puppy. I allready have a better pair of speakers, but I'm doing this to prove a point to someone who was swearign up and down that dave wilson is the wonderfull wizard of oz and his designs couldn't even come close to being duplicated. So far I am pretty close to the materials used, and the techniques employed. I also have access to a spraybooth to do the final finishing and I am encasing the speakers in an epoxy based finish to even out and seal the cabinet prior to painting. The only thing that will remain when I'm done is this darn crossover. I truly hate building crossovers. MY last pair took 3 months to find the correct crossover, and I'm still not completely thrilled. When I'm done i have another friend who wants to buy them. Even the real one's really arn't my cup of tea. Thanks

[GuyPanico]

My newbie method would be to use an equalizer.

[sreten]

Hi,

Checkout : http://www.deadwaxcafe.com/vzone/david/david.htm

/ Sreten.

[Salas]

Two 90 dB woofers add up to 96dB in parallel. In practice you gonna get 95 accounting Rcoil loss assuming that the stated sensitivity is accurate. I would use them in series to get 90 dB @ 16 Ohm but with half travel and much less distortion. In this scheme of things the mid will be alright since it gets boosted by the sidebands. The tweeter you can cut down with resistors. Any way it is going to lose 1 - 1.5 dB when it sees a cap in its signal path.

[sasha]

From my experience, even if you have drivers with same sensitivity
it ends up sounding too bright. So first build the speakers,
use active crossover (if possible) to find right cross-point and even more important to mach levels and than You might find that mids are just OK and tweeter will be probably too loud.
Good luck.

[rcavictim]

Originally posted by salas
Two 90 dB woofers add up to 96dB in parallel. In practice you gonna get 95 accounting Rcoil loss assuming that the stated sensitivity is accurate. I would use them in series to get 90 dB @ 16 Ohm but with half travel and much less distortion. In this scheme of things the mid will be alright since it gets boosted by the sidebands. The tweeter you can cut down with resistors. Any way it is going to lose 1 - 1.5 dB when it sees a cap in its signal path.

Two identical woofers in parallel give 3 dB sensitivity increase but with a SS amp will approach a 6 dB boost in SPL because they make the amp deliver 3 dB more power, hence your 6 dB. This can be confusing to some and does not work in a tube amp or transformer coupled SS amp situation.

I have had trouble placing 8 ohm woofers in series because if you look at the impedance curves most woofers see a large rise in Z in the bass frequencies (peak of rise at their Fs) where you are using them. You could end up with 30-50 or more ohms Z at bass frequencies rather than the expected 16 ohms. The electrically derived damping gets shot to heck in the same way.

[Salas]

RCA Victim: Real points. I agree. Talking nominal impedances and not reflex sadle we always expect much more than nominal Z near Fb.
Still with an ss amp he is going to hit 95 and depending in his room modes and diffraction he may burn many dBs for BS comp. or not. So its a matter of trial on error if parallel or series is gonna work best. With tubes 16 Ohm sounds good also.