phl 3450/3451 lower midrange response and crossover

[thadman]

I've been doing some research and the PHL 3451 seems like an excellent driver suitable as a lower midrange. Other than some vague information, PHL doesn't provide much data concerning these drivers beyond thiele small parameters. I'd like to use them between 150 and 600hz mated to the ATC super dome.

#1 does anybody have FR graphs, distortion/csd graphs for these drivers? I'm very interested in FR graphs because these drivers are listed as high efficiency (100dB)...but at what frequency?

#2 How would these drivers handle a 150hz crossover (I'm going active, 24dB seems likely but 48dB is a possibility)? Could they still play with the utmost authority and fidelity at high SPLs, I'm not looking for any signs of strain. I'm not willing to cross any higher than 150hz.

#3 How much usable xmax do these drivers have. It's listed at 2.5mm, but how much of that is 99% strength?

#4 Where can I purchase these drivers?

#5 How do these drivers compare to the likes of 18sounds midbass/midrange offerings (10NdA520, 12NdA520)

 

[Nelson Pass]

#2 How would these drivers handle a 150hz crossover (I'm going active, 24dB seems likely but 48dB is a possibility)? Could they still play with the utmost authority and fidelity at high SPLs, I'm not looking for any signs of strain. I'm not willing to cross any higher than 150hz.

Hell, I cross them at 60 Hz with a single-pole and they don't
burp.

 

[Cloth Ears]

Re: Re: phl 3450/3451 lower midrange response and crossover

Hell, I cross them at 60 Hz with a single-pole and they don't
burp.

Ahhh! The Rushmore. I always wondered if they were the 3450. I never thought that they would go as low as that, but I might have to change my crossover a bit now.

Thanks, Nelson!

 

[thadman]

At 150hz, won't we effectively be operating in 1/8th space if placed in a corner? Thats an extra 18dB vs full space.

377cm^2 (.375mm linear excursion) should achieve 92dB at 150hz

92dB operating in 1/8th space=
20(10^(92/20))=796214.34

796214.3411(8)=6369714.73

20log(6369714.73/20)=~110dB

 

[Cloth Ears]

Hi thadman,

From the literature on Nelson's Rushmore:
Within “Rushmore” there is sufficient Single-ended “Class A” amplification to routinely achieve 120 dB peaks with negligible acoustic distortion.

This includes a 3450 high-passed at 60Hz. So, if you can believe Nelson (and many do) then crossing at 150Hz should provide no problems...

 

[thadman]

It has a 90(+/-18)hz free air resonance, and you're operating it down to 60hz. I'm not questioning your experience, just wondering if we're talking about the same driver.

 

[Magnetar]

I had the 3451 - using it below 200 cycles is just plain nuts.