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tnc
01-28-2007, 08:59 PM
Can someone please educate me on this L-pad calculator thing:

According to this website:

http://www.carstereo.com/help2/Articles.cfm?id=18 (http://www.carstereo.com/help2/Articles.cfm?id=18)

My horn/tweeter JBL 2416 (4 ohm) driver is 109db efficient and my woofer G135A-8 (8 ohm) is 102db efficient. If I want to match the level of woofer and horn/tweeter, do I enter 7db in the "Enter Desired Attenuation" box.

It will be a simple 1st order crossover design. I am a newbie and need some help - please, pretty please.....

Zilch
01-28-2007, 10:20 PM
Yes, basically.

2416H-1 is nominally an 8-Ohm driver.

What is G135A-8?

Also, what horn are you contemplating?

Are these drivers in some JBL product together?

tnc
01-28-2007, 10:44 PM
These are from JBL G-734 cabinets that I got from a local thrift store. G135A-8 is a 15" woofer, horns are JBL 2371. You can view the specs here:

http://www.jblproservice.com/pdf/G-Series/G-734.pdf

Zilch
01-28-2007, 11:15 PM
O.K., you're asking in other threads whether they're suitable for home use.

Is there something you don't like about the way they sound for that purpose?

I'd start with a variable 8-Ohm L-Pad, and once my circuit was working, use equivalent fixed resistors from my final setting.

The 3.2 Ohms DC resistance on the tech sheet is not the impedance.

That's a 90° x 40° horn, but not a well regarded one, 2371.

I've worked with 2416H-1 on different horns. There's a more recent horn of similar dispersion pattern that'll sound better, and only costs $10. Buy a pair of those to try and compare. #338800-001

I assume you're going to repackage the system in new cabinets, because the dimensions of this horn are different.

That MAY also get you better bass out of the woofer.

The system was designed for sound reinforcement and musical instrument use. Think nasty loud.... ;)

http://www.jblpro.com/pub/obsolete/G-Series.pdf

tnc
01-28-2007, 11:25 PM
"O.K., you're asking in other threads whether they're suitable for home use.Is there something you don't like about the way they sound for that purpose?" I feel like they can sound lot better than they should be, maybe different crossovers or low frequency drivers.

338800-001 - Which horns are these and where can I buy them. Thanks.

Zilch
01-28-2007, 11:37 PM
338800-001 - Which horns are these and where can I buy them.JBL Pro Parts online.

http://audioheritage.org/vbulletin/showthread.php?p=132587#post132587

Pics of 'em are plastered all over that thread....


I feel like they can sound lot better than they should be, maybe different crossovers or low frequency drivers.Do you see that this is a slippery slope?

You're going to change horns, different crossover, maybe different woofer, different cabinets ... you're left with 2416H-1s, and you'll be considering alternatives for those, too.

All that's fine, IF you're into experimenting and learning. JBL very likely made them sound about the best they could sound using that combination of drivers in that size box.

I don't think you're going to get a lot of mileage outta just switching to 6 dB crossover slopes and lowering the frequency, but it'll be fun trying.... :thmbsup:

tnc
01-29-2007, 12:49 AM
Zilch,

I've searched long and hard but could not locate those horns anywhere. They must be out of production. Thanks for your help.

Zilch
01-29-2007, 12:57 AM
No, no. They're used in a bunch of current products. You just order them through JBL Pro Parts:

http://www.jblproservice.com/parts.html

Here's the horn list. $9.90 each:

http://www.jblproservice.com/pdf/Horn%20List/Horn%20Parts%20List.pdf

tnc
01-29-2007, 01:12 AM
I got you - will get them tomorrow - I guess I can't lose for $10 a shot and use them for future projects. Also I will take you advise and just leave the set the way they are. I guess JBL mate these G135 and 2416 together for a reason. Many thanks for the advise and recommendation.