1-3/8” x 18 TPI Compression Drivers ?

[MisterDK]

Wondering if many of you have played with different 1-3/8” x 18 TPI compression drivers. I see that parts-express has a good selection of them and I’m curious to know how Ti diaphragms sound compared to say, a polyimide or phenolic.. Also, if a horn speaker is played at lower volume than it was designed for, can a smaller diaphragm work as well as a large one or will the expected frequency range just be higher as a result?

In case you’re curious as to why I’m asking, it’s because I dragged a pair of old Peavey SP-1 Series III PA speakers into my living room (!) and want to find compression drivers better suited for indoor use (but my living room is fairly large). I want to find some that sound smoother than the original Peavey 22a, which, while they are working well, do seem a bit.. potent. Any recommendations for something smooth and subtle - and affordable - in a 1-3/8” x 18 TPI mount?

 

[Tooker]

Have you made any progress on this? I have been playing with some Peavey SP-5ti's because they have 100db/w efficiency and a low crossover for pro gear of 1200hz. They can make a 300b SET with a powered sub sound like a powerhouse in a home setting. The treble is a bit "larger than life" and I think taming it would make them easier to listen to.

 

[BillWojo]

It's typical for horn loaded speakers to have attenuation built in the crossovers for the horn compression drivers to tame them.
Altec horn loaded speakers have woofers in the 99 db range yet the compression drivers may be around 106 db or higher range. In that case, without attenuating the compression drivers they would over power the woofers.
You need to find a way to attenuate the compression driver.

BillWojo

 

[MisterDK]

Have you made any progress on this? I have been playing with some Peavey SP-5ti's because they have 100db/w efficiency and a low crossover for pro gear of 1200hz. They can make a 300b SET with a powered sub sound like a powerhouse in a home setting. The treble is a bit "larger than life" and I think taming it would make them easier to listen to.

Still haven’t tried changing mine out and haven’t done enough research into it. The original Peavey 22A drivers really don’t sound too bad; they seem to be getting a little smoother. Still want to re-cap the crossovers in these SP-1 MkIII cabinets. Though they sound crisp and clear with decent bass, the upper range horns do seem overpowering. After I go through the crossovers I’ll look further into better (smoother?) compression drivers.