Setup

Head Unit
Alpine CDA-9807

Amps -
JBL px600.2
Alpine mrp-f240

Speakers-

Alpine spx-137r component
Alpine spr-174a 6 3/4 2-way

Sub -
Alpine swr-1241d


Had this system for about a year before getting the mrp-f240 and it works fine. I tuned the mrp to my head unit and it ran flawlessly, no distortion at max volume. However, now my sub sounds awful. Very echo-ey and raspy, little boom and punch like it had beforehand. I have a feeling this is a simple solution, anything I can do?

 

what are your gains and freq set at on your amp?

 

2 channel amp or 4, bridged?

 

px600.2 is 4 channel, and its bridged with 1 sub

 

why do you have a 4ch amp running a sub? How is it bridged?? Are ch1 and ch2 bridged?? 3 and 4??

 

you will be under 1 ohm bridging that

 

Well that sub is a dual 4 so it could only be a 2 or 8 ohm load. I am assuming that its a 2 ohm load. In that case there seems to be a few problems.

1. Is that the px600.2 is actually a 2 channel on jbls site. Are you sure its not the px300.4 or something?

2. Is that the px600.2 doenst look like its rated down to 2 ohms so that could be part of the protblem. Also is this just a recent problem?

Have you used the px600.2 before and it sounded fine? The reason I ask is that it looks like it has the dbo circuit and one guy found out that it will cut the low end no matter where it is set and there is no way to defeat it. Maybe try adjusting that to see if it helps. If not maybe you can borrow another amp and try it on the sub? Where are your crossovers set at?