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I have two 8" speakers mounted on Advanblack 8" lids. The speakers are Rockville RM84Pro's rated at 300W. They are connected to the sub channel of a JLAudio HD900/5 Amp via a DDAudio DSI-2 DSP. The sub channel of the amp puts out 500 Watts, so I figure each speaker is getting 250 Watts more or less. The Rockville's are crossed at 100 (hp) and 6K (low pass). Equalization is flat, and gain is down to 42 (from a possible 60) although I did have it at 50 at one point . As you can see I blew one of the 8" speakers . Thing is I'm not sure why. Seems like amp power was within spec for the speaker, crossovers set pretty conservatively, and even now with the gain turned down - the other speaker will sound like it's hitting too hard, more like a crack than a thump - like there's too much travel. Is it just that the gains were too high? Do you guys seal the back of the speaker somehow or just use the saddlebag as the enclosure? I had a pair of Mmats 801's in there previously and I took them out in favor of the Rockford's as I thought I might be pushing them too hard. I'm thinking of possibly taking the 8" off the sub channel and either getting an amp with more channels, or potentially wiring them in with the tour pack speakers (Polk MM602's) but the frequency response of the Polks is way different than the 8" speakers. Thanks for any insight you can offer!
As one of the biggest rockville fan boys out there, I'm kind of surprised it blew like that. However it could just be the glue broke down. That set aside, I think all your numbers seem fine to me. I ran them in my lids for a while and had 0 issues. I didn't have them sealed off, just ran them in the lids with the bag as an enclosure. It's possible they're getting too much air / power. I'd maybe try bumping the crossover up a bit to 125. Also, did you meter the amp with a voltmeter or just by ear? I've always heard JL amps are underrated, so maybe you were pushing too much go go juice to them.
That seems to be the debate. The Rockville do sound good for the money, the question is longevity. If those are the frequencies you are after, another good economical speaker in 8" would be the Faital 8fe200.
Thanks for the input! I did end up bumping up the crossover to 120 and lowering the gain a little. The remaining speaker seems to be doing much better . I'll be throwing the original MMats back in so we'll see how it goes. On the plus side - the Rockville's are pretty reasonably priced so if I decide to go back to them it won't be too tough a pill to swallow .
Thanks for the input! I did end up bumping up the crossover to 120 and lowering the gain a little. The remaining speaker seems to be doing much better . I'll be throwing the original MMats back in so we'll see how it goes. On the plus side - the Rockville's are pretty reasonably priced so if I decide to go back to them it won't be too tough a pill to swallow .
If you throw Mmats back in, you'll probably need to lower gain a bit more. 150 watts is a good place to be with them. If you're around there, you can lower the crossover down to around 100
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8" speaker question...
. Thing is I'm not sure why. Seems like amp power was within spec for the speaker, crossovers set pretty conservatively, and even now with the gain turned down - the other speaker will sound like it's hitting too hard, more like a crack than a thump - like there's too much travel. Is it just that the gains were too high? Do you guys seal the back of the speaker somehow or just use the saddlebag as the enclosure? I had a pair of Mmats 801's in there previously and I took them out in favor of the Rockford's as I thought I might be pushing them too hard. I'm thinking of possibly taking the 8" off the sub channel and either getting an amp with more channels, or potentially wiring them in with the tour pack speakers (Polk MM602's) but the frequency response of the Polks is way different than the 8" speakers. Thanks for any insight you can offer!
. I'll be throwing the original MMats back in so we'll see how it goes. On the plus side - the Rockville's are pretty reasonably priced so if I decide to go back to them it won't be too tough a pill to swallow 
