What's Wrong Here?

[Kevlar 10+ year member]

Tonight I finally finished building my sub box for my 12" FI Q. Last week I had already installed my Hifonics BXi1606D amp, and run all of the wires for it, so tonight I put the sub in the car, and went about to set the gains...

Well, I put in my 60 Hz test tone, set my HU (Alpine CDA-9887) volume at the max level I would ever set it at (above which I get distortion), turned off the internal amp, and went back to the trunk to set the gains (the level/gain had always been set to the lowest level before this). Well, I hooked up my multimeter, and only got ~.2 V AC at minimum gain. Turning it up some yielded only a few tenths higher... wtf is going on here? I know I hooked everything up right (it's not -that- hard), I set the subwoofer to on on the headunit... is there anything I'm forgetting? Is it possible that I somehow severed one of the RCA cables when i fished it through under my carpet (using a coat hangar)? I'm going to either find another RCA cable tomorrow and try that, or at least check the continuity of my current cables (brand new KnuKonceptz cable). Or does it sound like the amp is FUBAR? I bought it used from a member of the forum (not naming names yet), who claimed it only had a few hours of light use before. Any insight? I want to get my sub working //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif

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[Rictamilk 10+ year member]

Try putting the gain at 3/4, those amps are cool like that.

 

[Kevlar 10+ year member]

I did. I turned it up to ~3/4 and only got ~.5 V AC.

 

[Kevlar 10+ year member]

Ok, update...

With the 'bass knob' thing at full, HU volume @ 20, and the gain at ~3/4, I get ~5 V AC... The max I can get is ~22. Something still isnt right here.

 

[regal8r 5,000+ posts]

turn subw setting up all the way to 15. do not mistake this with the bass setting which should be at 0. if that doesnt help, unplug the rca's and test ac voltage (sleeve to middle prong, in case youre unsure) when volume is turned up to loudest listening volume...the ouput voltage should be at least 2VAC...try that on both rca cables. if that isnt the case, maybe you hooked the sub amp rcas to either the front or rear rca channels instead of the subwoofer? also, if you are using the bass knob that came with the amp, trash it..its no good

 

[Pimpdaddyq 10+ year member]

I dunno if it sounds crazy, but try running new wires outside your car, or not hidden, to see if its a wire maybe.. instead of running all new ones and having the same issue..

Good luck.

 

[Kevlar 10+ year member]

There is no "subwoofer setting" - at least, not that I could find? It was just on or off for the subwoofer. Is there something else?