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View Full Version : adding 2470 driver to an 030



joetriley
03-28-2010, 08:47 AM
I have a home built 030 (?) I made in the 60's, a d130 15" with an 075 and a 2400 crossover. I thought I would add a driver and bought a pair of 2470s. They have no volumn compared to the original 030. They are 16 ohms, and I think my old set up is 8 ohm. Did I just buy something that is incompatable, or can this be fixed? Which crossover would I need? Are the drivers just blown? :banghead:I know most people on this site have a way better knowledge of electronics, but if you could help a dummy, I would be very grateful. Thanks, Joe at joetriley@hotmail.com

BMWCCA
03-28-2010, 08:56 AM
Did you just put them in place of the original 075s using the original N2400 crossover? What horn are you using with them? I don't think the impedance is the issue. Your 030 system is supposedly 16-ohm already. But you need a more proper crossover to even begin to try to integrate the 2470 into your existing system.

Mr. Widget
03-28-2010, 09:25 AM
I have a home built 030 (?) I made in the 60's, a d130 15" with an 075 and a 2400 crossover. I thought I would add a driver and bought a pair of 2470s. They have no volumn compared to the original 030. They are 16 ohms, and I think my old set up is 8 ohm. Did I just buy something that is incompatable, or can this be fixed?No, but you do need to know what you are doing... pulling parts randomly out of the air is a tough way end up with spectacular results.

The impedance mismatch is not an issue at all. It is quite common to use 16 ohm compression drivers with 8 ohm woofers. Then there is the fact that JBL was a bit loose in their impedance designations back then anyway. There are many, many threads discussing that topic.

Back to your issue... to make those components work as a well balanced system, you really should have a custom crossover network. Short of hiring someone to do it for you or finding a generous soul to help you, you could get by with a pair of N1200s (3120) and N7000s (3105). The numbers in parentheses are the identical networks from JBL Pro.

You will also need an appropriate horn. Which horn to use is largely a matter of personal taste as well as application requirements.


Widget