D130 Generational Differences? Or identical?

[Johnny_Law]

Hate to cross-post with AudioHeritage - but seems like more folks are active here.

I've got two D130s that are destined for use in my 030-loaded C40 cabinets.

They both measure around ~6.5ohms DCR and appear pretty much identical other than the binding posts and labels.

I wanted to check in here to make sure they are functionally identical and can be run as R / L?

Also, I'd love to know if I can change out the binding posts on the earlier one, as they are basically just posts without any kind of clamping for the wires.

Thanks in advance for any help here!

Newer one:





Older one:

 

[toddalin]

Appears to be a bit of difference in the curvature of the magnetic structure, but probably does not affect the sound. Just look at the difference between the professional series and consumer series structures, which is more dramatic.

With one being considerably older than the other, I would try to find two of the same generation. At the very least, I would have both magnets recharged, because AlNiCo loose strength with time, so the older one would be expected to be a bit weaker.

 

[Johnny_Law]

Thanks! I wonder if I can measure the flux density at home - or maybe by proxy, if I can measure sensitivity of each somehow with home equipment.

The cones / dust caps do look identical - from the front you can't tell them apart (other than the difference in the wear on the Al dust caps).

 

[toddalin]

Thanks! I wonder if I can measure the flux density at home - or maybe by proxy, if I can measure sensitivity of each somehow with home equipment.

The cones / dust caps do look identical - from the front you can't tell them apart (other than the difference in the wear on the Al dust caps).

Yes, you can use Woofer Tester 2 (or equivelent) to check the various T/S parameters and determine the BL, which (with all else being equal) is in direct relation to the strength of the magnet.

We did this on one of three 2205s after I had them "shot" and the BL was still a bit low. I had them re-shot (no charge) and it came up a bit above spec.

 

[Johnny_Law]

Yes, you can use Woofer Tester 2 (or equivelent) to check the various T/S parameters and determine the BL, which (with all else being equal) is in direct relation to the strength of the magnet.

We did this on one of three 2205s after I had them "shot" and the BL was still a bit low. I had them re-shot (no charge) and it came up a bit above spec.

Looks like a cool program - wonder if there's any freeware out there that can check BL.

 

[Johnny_Law]

So Bao at Speaker Repair Pros confirmed that the D130s are functionally identical. I'll be bringing them down to him for magnetization as soon as I set up an appointment.

 

[toddalin]

Bao does good work and has probably done more JBL D130s than about anyone, except the old factory workers.