Need help designing Modula MT + Bass Bin

[atx_hometheater]

Hi folks,

What sort of changes need to be made to the Modula MT crossover to use it in a three-way with the JBL LE14A woofer?

I don't expect perfection, but if someone could help me get into the ballpark, I would appreciate it. Even if it means using an L-Pad.

I've attached the only t/s #'s I could find for the JBL LE14A woofer. It will be in a 60L enclosure tuned to 30hz. The Module MT will sit on top of this unit.

Any help with the crossover would be appreciated.
I cannot afford an outboard processor & amp setup to run the LE14A's separately. So it needs to be a three-way crossover.




Here is the normal Modula MT crossover by Jon Marsh:

[JonMarsh]

I'm just flying back from the East coast, and will give the some thought. Problem may be sensitivity match up. Also. A good passive crossover might cost as much as a cheap or used plate amp- will toss out some ideas to consider

[atx_hometheater]

Hi Jon,

Thanks for the input!
I do have all the components for the standard crossover. Hopefully this is as easy as just adding a few extra components.

I'm on a home remodel budget, so there is no cash leftover for amp and active crossover, unfortunately.

[Face]

Hi Jon,

Thanks for the input!
I do have all the components for the standard crossover. Hopefully this is as easy as just adding a few extra components.

I'm on a home remodel budget, so there is no cash leftover for amp and active crossover, unfortunately.

Most plate amps have a built in crossover. Your best bet is to build the TM sealed and follow Jon's advice.

[engr_dave]

Most plate amps have a built in crossover

All of the plate amps I have looked at have a low-pass. None of them have high pass (the RCA "out" jacks are pass-thru). I suppose this is OK if you are matching the natural rolloff of the Modula... but I hate to see all that amplifier power wasted, and modulation distortion created, by running the Modula's full range.

[atx_hometheater]

Maybe I'm using the wrong term when I say "bass bin"?
I'm looking for more of a stereo three way. A popular crossover point between a woofer & midrange seems to be 500hz, though I'm not stuck on that number.

The JBL LE14A is phenomenal up through 500hz and even 900hz.

Jon Marsh has an incredible reputation throughout cyberworld. I will certainly follow his recommendations, provided it falls within my meager budget. In this case, being less than $100 to spend on any crossover bits that need to be added to the crossover parts I already have for the Modula MT setup.

If the LE14A doesn't work, then I would consider selling it. They seem to fetch on eBay between $100-$250/pair depending on condition. I could use the funds to purchase a different woofer. Though I really like the LE14A's.

My goal is a musical full-range speaker capable of reference levels.