I installed 2 12" RF HX2's into a 1.4cubic foot per chamber box on Friday. I am running them with a Crunch DS-4002 which does 400x2 at 4 ohms, with 4 gauge wire.
My subs are wired in series and then parallel bridged to the amp.

I am using the factory CD player in my '97 Nissan Pathfinder. When I installed the speaker-level to line-level converter, I cut the left/right +/i and soldered the wires with the stripe to each channel's +. I'm not 100% sure i got the wiring correct because I wasn't able to find any information on the car's head unit.

I have the converter's "gains" turned all the way up, and I have the amp's gain turned all the way up. I have the punch bass +12db, and the crossover around 80hz.

The subs hit pretty hard, but I feel they should be playing a _lot_ louder. Its as if the input voltage comming from the converter isn't high enough. I have the bass set at 0 on my head unit and even here it distorts my door speakers a little. I can increase the bass slightly by turning up the bass knob, but it distorts my door speakers horribly.

What can I do to correct the "loss-of-bass", and what do you think the problem is? A guy from the local shop told me they should be playing louder. I'm open for all suggestions!

As an aside, an RF amp will take speaker level inputs directly to the RCAs. Just put RCA jacks right on the speaker wires and forget the convertor.

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Blow your mind - PORT your box!

First off, I would get ahold of the spec sheet for that amp, and see what the minimum input voltage spec is(that is what is required when gain is set to max). Then, using a volt meter set to AC volts, check the rca's at the amp (while playing a test tone, I usually use 50 hz) and see if you are exceeding that rating. If you are then voltage isn't very likely your problem. If you don't have enough voltage, then check to see if the Line-level adaptor is adjustable, and if it is turn it up some and recheck.

Next, and the most possible problem, I would check for phase problems with your wiring(since you said you didn't know if you had the +/- right). The easiest way to check this, is with the system playing at a moderate volume, disconnect one of the rca inputs from the amp. If the volume goes down you are ok, if the volume goes up, you have one of the channels on the line-level backwards(in which case you can just switch one of them around and all will be well)

If these two problems aren't causing your delimma, I would try to get my hands on a deck to try in there with the same setup, and see if the sound gets better.

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Nathan Munson
Eastern Audio

team NOISY TOYS

Say there was a Nissan factory amp somewhere in the car, then would the head unit output thats passed thru the converter make the signal in the RCA's even lower? (than un-amplified signal passed to the car's amp)

I guess I should ask someone that works for Nissan..

Does the converter take the high signal and reduce it to a certain voltage no matter what the voltage was to start out with, or does it make any signal it gets lower?

I am wondering what hooking the RCA's right into the right +/-, left +/- on the head unit would do. I don't want to fry the input section of my amp by having the input voltage too high. I'll see if I can get my hands on a voltmeter of some type.

I hope that wasn't too hard to follow