The 500/1 has enough settings to be able to easily negate the bass. For starters you have a small switch that will do an easy job of cutting the sensitivity to the input source (the low/high input voltage switch - set it to "HIGH" and it will be less sensitive, producing lower volume). Then you also have your input sensitivity (aka gain). You can also adjust your low pass filter frequency to limit what goes to the subs as well as turn down the bass boost.

If you have your amp set up completely on the low side, you can probably stop those subs from making even the slightest rumble. You've got one of the most versatile amps around.

On the JL site, go to the docs section, find a page that uses subs as close in properties to the ones you have and set the amp up to the recommended defaults. Then go from there. First thing to do would be to adjust the sens switch and rotary to your liking.

Bruno