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New or vintage crossover for A5 VOTT

I have a pair of 805 horns and 288 drivers. I need to find some 825/828 locally (or build some) and get some 515 drivers. My plan has been to build some Hiraga xovers to use with that setup.

And like Tom posted, they have the values listed for both 8 ohm and 16 ohm loads.
 
Selmerdave said:
The Hiraga crossover would seem to be a no-brainer here...
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It wouldn't be hard to build. I am going to look into this. I've seen it, but since it was older I didn't give it a lot of thought.

While I was perusing the sites and manufacturers I came across This DBX PA2 clone, This Venu360 clone, and this Ashley. A guy on one of the AVS sites said he purchased the PA2 clone and is quite pleased with it. It had DBX logos underneath the Sinbosen stickers.
 
The Hiraga is an older design, but it’s still only about half the age of the speakers. Haha

Also if it’s a good design, who cares how old it is? The Markwarts 604 xover has been around for a little while as well. And it’s still the best 604 xover IMO
 
While sourcing the components for the Hiraga crossover, I think I'll use the polypropylene/oil filled can capacitors although the resin filled capacitors are cheaper. Having some trouble finding a 6.6mH inductor. Would I need to cut down an inductor with more inductance? My HF drivers are 20 ohm and not 24 ohm. Would close enough be good since my HF driver does not match his? I'm thinking of adding an L-pad or autoformer for HF attenuation.

I'm still going to search for a deal on a DSP in the meantime.
 
I use motor run caps for my horn speaker xovers. GE and Genteq are the brands I normally use. There are other good ones as well.
 
MissionX said:
While sourcing the components for the Hiraga crossover, I think I'll use the polypropylene/oil filled can capacitors although the resin filled capacitors are cheaper. Having some trouble finding a 6.6mH inductor. Would I need to cut down an inductor with more inductance? My HF drivers are 20 ohm and not 24 ohm. Would close enough be good since my HF driver does not match his? I'm thinking of adding an L-pad or autoformer for HF attenuation.

I'm still going to search for a deal on a DSP in the meantime.
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If you have a meter it's easy to wind off a higher inductor to the exact desired value.
 
MissionX said:
My HF drivers are 20 ohm and not 24 ohm.
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Measure them, ideally before you start ordering components based on assumption.

Consider that Altec may have changed the convention by which they measured the HF impedance rather than changing the actual impedance of the driver. Consider it, because they did.

Hint: tuning an active system whether analog or DSP is not any more arduous than properly designing and building a good passive network.

Tuning a passive network can have a significant cost in additional components and labor/time.

Tuning an active system is done largely in real time, on the fly.
 
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bowtie427ss said:
Knowing the measured impedance @ the desired XO frequency is nearly requisite.

Do we know that the 288B's have the original diaphragms in them?
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How do you measure impedance without special equipment?

One of them is original.288B(1).jpg 288B(2).jpg
 
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MissionX said:
One of them is original.
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They need to match, preferably with correct diaphragms. The current replacement diaphragm is a 12 dollar titanium waste of time and effort.

I wouldn't overlook making a call to Bill at GPA to have a dialog about what you have, and how you might proceed from here.

On the other hand, if you're happy with how those drivers sound currently, just buy a pair of off the shelf crossovers and be done.
 
Maybe sell the one original diaphragm to help fund a new pair of GPA diaphragms. I think these have to be slightly modded to fit the new style diaphragms right?
 
Nowadays it’s so much easier to test drivers at home though. With DATS and REW. I’m sure there are other programs as well.
 
elitopus said:
Maybe sell the one original diaphragm to help fund a new pair of GPA diaphragms. I think these have to be slightly modded to fit the new style diaphragms right?
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I'm still sourcing an OE diaphragm and will probably end up buying a complete driver and robbing it. I've often thought about the GPA diaphragms, but don't really want my drivers modified. If they are just changing it to spade terminals, anyone can do it. I'd like to know more about it. I contacted GPA about 15 years ago about reconing a pair of 515s I had, and as I recall, he wasn't to responsive to my requests so I ended up going elsewhere.The one speaker sounds pretty decent and the other one is in need of a crossover, that's why I started the thread.
 
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