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GrooveControl
06-10-2012, 06:44 PM
Hi all, great site. I've been reading for months.

It's been over thirty years since i first built a pair of 4560 bass horns with the matching 12" mid cabinets. In the 70s and 80s I used them for DJing and band PA use. After a 20yr absence from the hobby, I have started building speakers again. I've built several pairs over the past few years, but Not JBL, and nothing one person could not pick up.

Every nightclub I've ever worked in has had JBL. I miss that sound and have developed a serious itch that needs scratching. So i started collecting the components, 2035hpl, 2245j, 2380a and 2405 tweets. The woofers were in mint condition at a good price. How could I say no?

Now i'm designing the cabinets. My plan is to go passive xo at 800hz and 8khz.

What do you think of the cabinet designs at the link below? I'm open to any comments, crossover suggestions etc. I hope to start the cabinets in July. I'll post pics as I go.

Thanks.

https://lh6.googleusercontent.com/-w3t1Z6sYGSU/T9U4Ej4i8HI/AAAAAAAAAGM/zrZL2DDdYIo/s640/42332986.JPG

GrooveControl
06-11-2012, 09:11 AM
Here's the picture I couldn't post last night.
55970

Ruediger
06-11-2012, 10:00 AM
Align the drivers vertically in a line, and place them at a side of the cabinet, not symmetrically in the middle. See the 4430, and imagine a tweeter added on top.

Ruediger

4343
06-11-2012, 01:58 PM
Align the drivers vertically in a line, and place them at a side of the cabinet, not symmetrically in the middle. See the 4430, and imagine a tweeter added on top. Ruediger

Yes, like the first design, but with the tweeter above the mid horn like the second one.

Sort of like this hacked version of your design, only closer together.;)

Nowadays, putting the horn as close to the woofer as possible is preferred for coherent crossover, and radiusing the outer edges of the box can help with diffraction. Think about rear mounting the woofer to put the voice coils closer to a common plane, I like the old front horns because they help with that too. Hmm, I have those same components almost, laying about, but I do like them separate for moving about...

GrooveControl
06-12-2012, 07:07 AM
I still can't decide if I want the tweeter in or out of the cabinet. I guess I sold too many of the Radio Shack super tweeters back then.

Keeping the tweeter out reduces the bulk of the box, but I'll need to build an attractive bracket.

Can anyone recommend of a good xo for the 2035hpl and 2445J?

55981

Mike F
06-12-2012, 08:29 PM
A 2405 is just too pretty to be hidden away in a box

4343
06-12-2012, 10:56 PM
...

Can anyone recommend of a good xo for the 2035hpl and 2445J?

3110A is what you want, for 8 ohm LF and 16 ohm HF with "HF Boost":

http://www.jblproservice.com/pdf/Network Schematics/3110A Network.pdf

There is also a discussion today on winding the tapped inductor:

http://www.audioheritage.org/vbulletin/showthread.php?33057-Alternative-to-tapped-inductor-in-3110a-or-3115a&p=334485&viewfull=1#post334485

GrooveControl
06-14-2012, 10:38 AM
I think I'm done with the enclosure design. Here are the dimensions in case anyone is interested.

I have a bathroom reno to finish first. I hope to start in July or Aug. I'll posts pics as I progress.

Thanks for the input.

56042

Sundown
06-14-2012, 11:11 AM
I think I'm done with the enclosure design. Here are the dimensions in case anyone is interested.

I have a bathroom reno to finish first. I hope to start in July or Aug. I'll posts pics as I progress.

Thanks for the input.

56042

Nice! What program did you use to design the cab?

Mike F
06-14-2012, 11:54 AM
Align the drivers vertically in a line, and place them at a side of the cabinet, not symmetrically in the middle. See the 4430, and imagine a tweeter added on top.

Ruediger

What is the advantage to that design?

grumpy
06-14-2012, 12:03 PM
... because then, diffraction/reflection effects that depend on driver to sidewall distances
don't add up as well (notches/peaks due to these effects aren't as deep/peaky).

If those effects are there, putting drivers in the center will cause the effects
to be coherent and additive.

If the cabinet/driver design is such that those type of effects have been minimized,
the issue is less of a concern.

GrooveControl
06-14-2012, 01:40 PM
Nice! What program did you use to design the cab?

Thanks, Microsoft Visio