E140 in D140 need Specs for Box design

[jkolze]

I have a JBL D140 that I had reconed at a JBL dealer in 1995. They put in a E140 kit. I'm now building a 4.5 cu ft box for bass guitar and would like to know the proper dimensions for the ports. However, I don't know if I should use the E140 specs, as the magnet is different on the D140 and the E140. Any suggestions?

Does anyone know what the dimension of the ports should be? I'm guessing I'll need two 3" ports, but don't know how deep. I can get the software and figure this out, but I don't know if I should use the D140 or E140 parameters

I'll be running this setup with a late 60's Showman amp, and I also plan to use it with electric guitar.

[rgwalker]

I have a JBL D140 that I had reconed at a JBL dealer in 1995. They put in a E140 kit. I'm now building a 4.5 cu ft box for bass guitar and would like to know the proper dimensions for the ports. However, I don't know if I should use the E140 specs, as the magnet is different on the D140 and the E140. Any suggestions?

Does anyone know what the dimension of the ports should be? I'm guessing I'll need two 3" ports, but don't know how deep. I can get the software and figure this out, but I don't know if I should use the D140 or E140 parameters

I'll be running this setup with a late 60's Showman amp, and I also plan to use it with electric guitar.

D140s in Showman cabinets have no ports. - Bob Walker

[jcrobso]

With the E140 cone you should use the info in this PDF.
You could just use a 4.5 cu ft sealed box or use the Thiele-Small parameters for your port size.;)

[rgwalker]

With the E140 cone you should use the info in this PDF.
You could just use a 4.5 cu ft sealed box or use the Thiele-Small parameters for your port size.;)

Thank you. I'll check it out.

Bob W

[Loren42]

The best thing to do is measure the driver's T/S response. You can do this yourself (I suggest getting Vance Dickason's The Loudspeaker Design Cookbook).

Vance outlines the process for getting all of the T/S parameters you need and then you can use software to design the box.

It's not hard, but does take some time to do all the steps. However, the end result will settle your question for you because you have the actual driver parameters for your hybrid driver.