Trouble with subwoofer install, suggestions?

[jawn101]

I don't know if anyone will have any answers for me, but here's what's going on:

DMC-CA sub box. JL XD300 amp. JVC head unit with subwoofer outputs (RCA cables).

Power and remote turn-on to the JL amp are hooked up properly and the amp powers up when the stereo is turned on (and off/off), no problem there.

Problem is that there's no audio out of the sub. I've checked that the RCA output cables are hooked to the correct jacks on the head unit and the amplifier. The subwoofer output on the head unit is enabled.

The troubleshooting guide for the amp says to slap an AC voltmeter on the input wires, and then again on the output wires. Pretty obvious stuff, except it says to be looking for about 5V steady and my voltmeters only go down to the 200V AC range. They show the same 000.1 volt to 000.0 volt fluctuation whether the leads are on one of the wires or not.

I tried to open up the DMC-CA sub box to make sure the terminals were actually connected inside, but after I removed the screws and the panels weren't obviously loose I didn't pry any further. Didn't want to risk messing up the finish or damaging the enclosure.

I don't have any other equipment to hook up and test with - no spare amps, speakers, head units, etc. Anyone have any ideas?

[Tillsy]

I don't have any other equipment to hook up and test with - no spare amps, speakers, head units, etc. Anyone have any ideas?

Is that sub passive or active?

[jawn101]

Is that sub passive or active?

The sub itself is passive, but I installed a dedicated amp to drive it. The amp comes on but there's nothing going on at the speaker end.

[Tillsy]

The sub itself is passive, but I installed a dedicated amp to drive it. The amp comes on but there's nothing going on at the speaker end.

To test that amp is doing its job all you need is an audio-out feed - doesn't have to be a LFE specific feed as your amp is going to make the subby pump out (crappy) audio regardless. You mentioned not having head units, stereos, etc to test with - but don't forget even your Blu-ray player, DVD player, or settop box will all have audio outs on them so just plug one of those in so you can narrow down whether your problem is here or elsewhere.

[jawn101]

To test that amp is doing its job all you need is an audio-out feed - doesn't have to be a LFE specific feed as your amp is going to make the subby pump out (crappy) audio regardless. You mentioned not having head units, stereos, etc to test with - but don't forget even your Blu-ray player, DVD player, or settop box will all have audio outs on them so just plug one of those in so you can narrow down whether your problem is here or elsewhere.

Wow, that is a great idea. Should have thought of that! I will do so right away. I think I have one of those cables that lets you hook your ipod to RCA jacks laying around, that would be perfect.