Posted by Adrian Mack [ 203.190.196.12 ] on January 16, 2004 at 03:22:13:

In Reply to: foam horns and heavy drivers posted by Joel Tatelman on January 15, 2004 at 18:19:11:

Hi Joel

I'm glad that you picked up those 2380 horns that we talked about over the email. They really are a lot better suited to your application than the 2382's.

If your using the Pi Crossover (which I initially suggested), then that'll augment the high frequencies and makes a UHF tweeter not required. You can use a UHF tweeter if you leave out the compensation circuit on the compression driver, but I'd rather not do it this way. Crossover points this high shifts crossover nulls closer towards the on axis position, and the extra crossover point itself introduces further means for nulls, especially when its this high. I think in a setup like yours, a UHF tweeter just isn't needed for good performance.

I'm not sure of which JBL models use the 2235 in particular, but you shouldn't be worried about its performance. Like Wayne said, it's a great driver. As for copying baffle spacing/port dimensions etc - there isn't any need for that. I made a couple of suggestions for the 2235 woofer in one of my emails to you a while ago, and also some reccomended port sizes for both low and high power applications. You'll get all the help you need regarding the rest of the setup - baffle spacing, crossovers, etc from people on this forum, and with the parts your using, you'll definitly end up with a very nice sounding system.

I'd probably use a brace for a heavy compression driver too. It should hold itself up, but the 'mere thought of snaping or damaging the horn flare, especially when moving the cabinet around, is horrifying. I've used a brace for the compression driver to rest on in my 3-way towers to avoid damage to the horn flare.

Adrian

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