Low output from sub? >>>

[SeekingVidblain]

Hi there, this is my first time here, and it looks like a cool place to be //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

I was hoping someone could shed some light on this issue. I have an Alpine 7998 to a Sony 4-channel driving 4 Boston 5x8's, and a Rockford Punch 100z, bridged, and into an RF Series 1 10" sub in one of Rockford's own enclosures. The sub is facing the rear and in the trunk. The amps are connected via 4ga from the battery to a block and then 8ga from there to each. The grounds are also 4ga to 8ga, and the 4 is connected to the rear seat mount bolt. The Bostons are crossed from 80Hz and up, and the sub is crossed from 80Hz down. The crossover is built in to the deck. Everything operates fine with the exception of the sub.

The output seems quite a bit lower than it should, in my experience, and boosting the sub output on the deck only slightly improves this. I have tried different box positions around the trunk, and the best seems to be facing the rear.

I know this type of problem could have many causes, but I'm fast running out of ideas. Anyone?

Thanks!

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[GrnEydDvl 10+ year member]

Where do you have the gains set on your sub amp? Did you set them by ear or did you use a more objective method?

I assume the speaker is in a recommended factory enclosure and it has no leaks?

How do you have the sub wired? Series / parallel? Have you checked its impedence with a DMM?

Welcome to the forum.

 

[SeekingVidblain]

I guess I left out a few details, hehe.

The amp is operating bridged, and the gains are centered. The sub was purchased already enclosed and is new, so I can only assume the volume is leak-free. The sub is a single voice coil model, and is indicated as a 4-ohm model. I have not physically checked the impedance as of yet. (My job keeps intruding! ;-) )

 

[mannyb18b]

Well it is just a budget 10" Rockford woofer...sealed I suppose. Maybe your just expecting to much?

 

[SeekingVidblain]

Well, that is entirely possible. My taste far exceeds the pocketbook, as usual.

The enclosure is ported, and is some space-shippy RF design to ease airflow. I have built many myself in the past, but this was a lazy job, to be sure.

Thanks for helping, and I'll keep tweaking on it.

 

[acold7dusta 10+ year member]

what is your filter setting on the amp? (hpf, off, or lpf)

 

[SeekingVidblain]

The filter on the amp is defeated. The deck is filtering at 80Hz lp.