Curious question about JBL 2446/2445

[ac2]

Not sure if it makes sense....

but I have a 2445 and two 2446's and was wondering if I put a 2446 diaphragm in the 2445 will that make it a 2446? It appears from looking at them the only difference is the VC.

[ivica]

Not sure if it makes sense....

but I have a 2445 and two 2446's and was wondering if I put a 2446 diaphragm in the 2445 will that make it a 2446? It appears from looking at them the only difference is the VC.

Hi ac2,

Looking from the 'outside' 2445 and 2446 are ALMOST the same, but there are some important differences:
-2445 uses Ti diaphragm without the 'ribs' while on 2446 it is 'ribbed' diaphragm (these ribs enhance diaphragm stiffness)
-2446 has different phase plug relative to the 2445 (sometime 2446 phase plug is called "coherent" phase plug)

Due to the mentioned differences, 2446 has more stability round 10kHz, but over say 12~13kHz diaphragm oscillation become very large, while on the 2445 such diaphragm oscillation is less pronounced but starts almost after 10kHz, so the driver can be used almost up to 16kHz.
My experience with 2445 has shown deep narrow notch in the FR response near 10kHz.

I think that 2446 core can be used with 2445 diaphragm, and that would give the best compromise if no UHF driver is present.

regards
ivica