Barzilay with Altec horns? project advice

Hello there,

I am a long time lurker and this is my first post. I just got a pair of Barzilay cabs and want to fill them up with goodies. I plan on refinishing the cabs and then pull some parts from a couple of my four PA speakers. I have the following parts to play with: 2 X JBL D130F, 2 X K130, 4 X Altec 802-8G. The cab seems to be set up for a 075 Bullet, but it is probably better to let a mid horn handle the mids instead of the 15", correct? I appreciate any advice you can give me.

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I have decided to go three way with D130F, 2405 slot tweeters and an Altec 511B 802-g combo. Can anyone help me design a X-over?

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Originally Posted by MrZdur

I have decided to go three way with D130F, 2405 slot tweeters and an Altec 511B 802-g combo. Can anyone help me design a X-over?

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Not sure why you picked that combo, unless its just what you have right now.

Wasn't the D130F a wide-range musical instrument driver, and not a conventional woofer?

Building a hybrid design like that is a lot more DIY ... its not in my skillset or I'd offer help.

But in the couple years I've been visiting this site, what I have noticed is that when folks want to DIY and are not themselves crossover engineers, what a lot of people do is use an existing speaker design for guidelines. That way they just use the same drivers as a common 3 way speaker design used, then its just a matter of building a fresh copy of the original design but using better capacitors and such in the process.

Just a thought ...

AFAIK the D130f is just a high power version of the original D130. The C51 JBL Apollo used a D130 and a bullet tweeter (among other configurations). In this design the D130 went all the way up to 2500 Hz, where the bullet tweeter took over. I don't think it would be too wacky for the d130F to go up to 500Hz, where the 511B mid horn kicks in and then to have the slot tweeter play the upper registers. The efficiencies should match well.

Quote:

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Originally Posted by MrZdur

I don't think it would be too wacky for the d130F to go up to 500Hz, where the 511B mid horn kicks in and then to have the slot tweeter play the upper registers. The efficiencies should match well.

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I cannot speak for the D130F, but I can say I wouldn't take a 511B/802-g combo down to 500 Hz. Further, If I did take it below say 700 or 800 Hz, I'd use a steep crossover like 24db. This is based on my time trying 511B with 802-8D and an electronic crossover to try different combinations "on the fly". yes I know Altec did it. Perhaps that is part of the reason I don't care for some of the Altec combinations.. In my mind, not very many horns and 2" compression drivers sound good down to 500 Hz. Further, as far as I know, no 1" CD does. The 511B horn can sound quite good with the right driver. FWIW, the best I ever heard them sound was with LE-85 drivers crossed at 700 Hz 24db L-R and it was damped to stop some ring and foam was utilized to minimize diffraction.

There is a significant difference between a driver (woofer or CD) being able to cover a frequency range and a driver sounding good doing that range.

Look around. You'll find boatloads of information of horn/driver combinations and suggestions.

Thanks cosmos, that is just the king of info that I am looking for. I do have an electronic crossover and can play around until I find the sweet spot; that is a great idea. Time to start digging before I order x-over components.

here is a cross over used on a three way with the Altec horn and JBL woofer and tweeter,,

don't know the exact crossover points and Lpads are used in the horn and tweeter,,

you can also get some idea of various crossovers at:

http://www.diyaudioandvideo.com/Calculator/APCXOver/

Derry

That is exactly what I am looking for!