B-460 subwoofer noise problem

I have an exact cabinet copy of the JBL B-460. I set it up in my home theater with a re-coned 2445. I drive it with an Adcom 555 in bridged mode. When a DD movie puts out high volume to it it will put out an awful rumble. The cone appears to move clearly. I tried a 2440 and had no problems. I'm guessing that perhaps I have an electrical feedback problem? I was thinking of an 8-50 ohm damping resistor in parallel? Perhaps a problem at resonant frequency and might need a series resister,cap,coil in series tuned to the frequency? Any ideas or suggestions gentlemen?

Yeah, I'd probably try moving things around a bit. I think it is a bit strange that you had no problems with the 2240... it doesn't present quite as nice a load to the amplifier in that box as the 2245 does. In any case the GFA-555 is easily up to driving the B460. Have you run a frequency sweep on the 2245? Do it in free air and then in the box. 10 volts in from 20 Hz to 1200 Hz.

Anybody have any ideal what a B460 and the BX63 together would go for in good condition?

The last one a friend bought on Ebay was about $800. Shipping from Tennessee to Pennsylvania was expensive but the seller did a killer job of crating and it was mint. Prior to that another friend bought one for around $700. It was also in good shape. I think that one made the journey from Texas to San Diego unscathed. Funny how we have managed to get two giant speakers shipped without problems and we have managed to reduce five sets of Aquarius 4s to sawdust with with imbecile packing and shipping.

I Have viewed the ebay listings for the past 3 years and unless i missed them i can only remember seeing one offered and it did not make the reserve so it did not sell. I think the top bid was around $800.00http://audioheritage.csdco.com/vbull...ies/bouncy.gif

Saw a Nice one (with Bx63a) on Ebay go for $1226.51 in August of 2002
Mrbluster