i just got an alpine 9851, 4 channel f240 amp and polk momo 6500s installed. after like a week, the right speaker distorts (cracking sound from bass) whenever i turn the volume up or bass anywhere over +1 on the equalizer. the left one is fine.
the amp is bridged and runs 100w to each while the speakers can handle 125w. i turned the "bass" gain on the amp all the way and it just cracks harder. is the speaker blown? i played around with the bbe settings a few times at high volumes and am worried this caused the speaker to blow after like a week of use? thanks

 

Sounds like the speaker is blown (Jon might be able to tell you for sure).

Subs usually go from distortion. Turning the volume up to high and causing the amp to "clip" will cause it pretty quick, sometimes. When this happens a malformed waveform is sent through the sub and it can't reproduce it right.

Might be you have a bad speaker, could also be that it was tuned wrong. Did you install it all yourself or did you have it installed?

 

Hmm, I've got the exact same speaker w/ the exact same amp. The momo's seem to handle the power fine, but i've got a couple big subs so i've filtered out any real low bass going to them.

It does sounds like the speaker might be damaged. Any chance you had the gains set too high, or the filters set wrong? My gains are set pretty conservatively and it seems like i've got plenty of headroom w/ those speakers.

 

Sounds to me like the tuning was way off and then you turned it up and it popped the speaker. I would say your going to have to test the speakers on a different set up(bench test) and see if infact its blown. You very well could have blown the speaker though.

Did you tune it yourself or did a shop?

 

With that amp, channel 3 & 4 (which I assume you have your right side hooked up to) has a bass booster, and channel 1 & 2 doesn't. When you hooked up the amp did you make sure that bass booster was all the way turned off?? Where did you have your gains??? Did you have the filter set to off??

 

the gains were set pretty high and the bass gain for channels 3 and 4 were set about half way. i had a local shop install them.
and can someone explain the filters to me. can i set the filters so that the right speaker does not try to produce much bass. thanks

 

I dont know if you can filter the bass off JUST the left speaker....you can cross it over (if it has a HPF) at or above the low threshold of the speakers. You set the HPF to the frequency at which nothing below will hit the speaker (I have my x-over set at 80htz, as the sub picks up stuff below that).

john

 

You should have both of the gain settings at or below the halfway setting (that is the case with my kappa perfect component set, that amp has some power). The bass boost should be all the way to the left (off) and both the filters should be set to off...

Also, if the shop had the bass boost set to half way, I doubt they knew what they were doing. That setting is to be used if you are using channel 3 & 4 for a sub and 1 & 2 for some components, not if you are bridging the amp to just run components. So you might want to check that they have it hooked up right also. Did they run rca splitters?? By that I mean is there an rca going into all 4 rca inputs (channels 1-4)? When you fade the head unit to the left and to the right does it work like it should???

 

actually, listening to it again, i think its just that the door rattles. for some reason the door rattling sounds like the speaker cracking, but the sound comes the strongest about a foot to the right of the speaker. anyway to make the rattling stop?

 

Sound dampening material, like Dynamat Line the door with it...