YaMomma

Your talking about two different setups, the GS has a single 10inch sub in the rear deck along with mid-range woofers in the doors. From the brief search I did online the RX has mid-range woofers in the doors and no dedicated sub.

I would not use this setup with your application because if you start adding extra power to those woofers you will blow them. Your best route is to leave the existing speakers alone and add a 10 or 12 inch sub with an external amp. Since you don't have a trunk a 200 RMS amp with a decent sub will sound great. If you want to **** your neighbors off jump up to at 1000 RMS amp with 12's or 15's.

Most of what he did will still apply because you have to get a signal to the amp.

Don't worry about that because you shouldn't mess with those woofers.

Regardless of which route you take you must get a signal to the amp. Your nicer amps have a high level input. What this means is that you can splice into a speaker line which is already amplified by the ML amp and connect that wire directly into the high level input of the amp. The benefit is you don't need any additional equipment and don't have to run a remote turn on line. When the amp sees a signal it will turn its self on and off based on sound coming thru the speakers.

If you don't have a high level input then you need a LOC. The LOC will have positive and negative connections for a right and left signal and provide RCA outputs for the amp. You will however have to run a remote turn on line and some RCA cables.

I wouldn't stress to much about the frequency's, its one of those things where you start low and make adjustments according to what sounds good to you. It's more important in the GS because of the dedicated free air sub but you don't have that in the RX.

It doesn't matter if you go high level or LOC you need a signal for the amp. The easiest way is to splice into the speakers at the rear of the car. Don't cut anything, go to radio shack and get a splicing kit that will allow you to tap into the speaker line without cutting the wire. Although you could get away with only splicing one speaker I would do the left and the right rear speaker.

I assure you a single sub in a sealed box will make all the difference in the world!

DrexLex

Thanks. It looks like YoMamma has taken good care of your questions.

The amplifier has a gain control on the chassis, and then there's the remote gain control which I wanted up front for tweaking. I wanted both controls to sit nominally just under half of their rotation range. At those settings I found there was still a lot of gain from the speaker inputs to the speaker outputs. I was not looking for a lot of gain, just some headroom and the bass EQ. After tracing out the input stage I could see that rather than changing resistor values inside the amp I could just apply a short to the line inputs and that shifted the speaker-level input signal divider just enough.

I measured it and the 40 Hz EQ was actually 36 Hz. No real consequence.

I set the control to give me a 5 dB lift at the peak (36 Hz), which was enough to do what I needed to counteract the native bloated bass sound. This was determined by trial and error until I got the bass to sound as I wanted.

designo

iTrader: (6)

Thanks for detailed pics, very helpful.

nadz23

I've already ordered a JBL GTO-751EZ Mono 750Watt RMS. Perhaps I'll go the 12/15 route

Relevant Specs:
mono subwoofer amplifier
500 watts RMS x 1 at 4 ohms (750 watts RMS x 1 at 2 ohms)
frequency response: 10-280 Hz
variable low-pass filter (40-280 Hz, 12 dB/octave)
variable bass boost (0-12 dB at 45 Hz)
Simple Setup System with test tone CD for perfect gain setting
optional wired remote level controller available soon
preamp and speaker-level inputs (speaker wire-to-RCA adapters included)
switchable automatic signal-sensing turns on amp without need for remote lead
fuse rating: 40A x 2
8-gauge power and ground leads recommended wiring and hardware not included with amplifier


Will post back here as this progresses.

GenghiS300

This is awesome DrexLex, thank you for the informative post. I will have to try this out. But can you help explain to me what the RCA phono plugs are? So with these you will not need a set of RCA wires going anywhere correct? It it to just basically short it out to not need it? I never seen this before, thank you in advance.

GenghiS300

And I am looking at this Kicker ZX300.1 to power it, do you think that will work alright?

DrexLex

Yes, it will work fine.

The 300.1 does not have separate high level input terminals. All signals enter through the phono (RCA) jacks, and you set the switch to the high level position.

Once you have the system running, adjust the amp's chassis gain control as needed to match the system to the remote volume.

GenghiS300

So basically a phono jack is 2 rca connector jacks that will be connected via a wire that I will solder to make them connect each other?

GenghiS300

Thank you again.

DrexLex

A phono jack is usually a line level, 2-conductor audio connection. A phono plug is the ubiquitous connector as below.



The center is the "pin" and the longer arm usually grasps the outer shield (ground). In these amps the "ground" input is not actually tied to chassis, otherwise it will upset a bridge amp (which is what we have in our ML amps).

You are driving this from a subwoofer signal so only need to drive one of the two inputs -- leave the other open. Best to consult the manual for details for your specific amp. Do exactly as they say.

I guess Kicker changed things over time but used the same model number for 4 different models. I have the older series that has the separate HI level input, and looks like this:


The newer one uses the phono input for both cases:


See the amp pix full size at this website.

GenghiS300

Thank you DrexLex, you have been very informative. I will try this maybe this weekend.

L's TLS

iTrader: (1)

I know I am reviving an old thread, but I was curious if this would make the bass from the ML sub any cleaner? Its got plenty of thump but I'd like to clean up and tighten the bass in the vehicle. I'd prefer this method over adding another sub, but worst case scenario I'll add a JL audio 8" w7 or something.

Any help is appreciated.

DrexLex

If I understand your intent of "clean up and tighten," then I'd say yes. That was exactly the result of the mod I did.

And if you decide that you want to run a different sub, you'll need a new power amp anyway, so this mod gets you there with nothing going to waste.

L's TLS

iTrader: (1)

Awesome. I was hoping you were still around. That's exactly what I want, thanks for feedback!

Tantrix

so just to clarify, you are adding a separate amp for the ML subwoofer, which leaves the ML amp to just power the rest of the ML speakers in the car cabin right ?

does anyone know what size the ML subwoofer is ? is it a single subwoofer set up ? I'm more concerned with the ML subwoofer deteriorating at the rubber surrounds.

I used to have a 2001 LS430 and the surrounds on the cheap subwoofer were the first thing to deteriorate.