JVC KS-AX3002 Amplifier Installation

[Lokiel]

Installation Slideshow:

http://s490.photobucket.com/albums/rr26 ... =slideshow

Details:

I wanted to install an amplifier to get the most out of my JL Audio ZR650-CSi door speakers. Since I intend to get a roll bar installed, and the rear speakers in an SE are virtually useless anyway, I decided to go for a 2-channel amplifier.

I didn't want to lose any bootspace so needed an amp that I could mount in the driver's side tunnel, next to the fuel tank. The JVC KS-AX3002 amplifier looked like it would fit, here are its specs:

* Max. Power Output of 370W
* Continuous Power Output (RMS): 65W x 2 at 4 ohms, 90W x 2 at 2 ohms, 130W x 1 at 4 ohms bridged
* 2- or 1-Channel Operation
* Class-AB Circuit
* PWM Regulated MOS-FET Power Supply
* Frequency Response: 5Hz - 50000Hz (0, -3dB)
* S/N: 76dBA
* THD: Less than 0.04% at 1kHz
* HPF (150Hz, -12dB/oct)
* LPF (80Hz, -12dB/oct)
* Variable Input Level Control (0.3 - 6V)
* Gold-Plated Input Terminals (Power)
* Gold-Plated RCA Jacks
* Speaker Input Connector
* Protection Circuitry (Thernmal/Short Circuit/Overload/DC Offset)
* Anti-Pop Circuit
* LED Indicator
* Width 13.1 in
* Depth 8.3 in
* Height 2 in

I also bought an amplifier wiring kit but decided to use a shorter RCA cable that I had since I only needed a 2.5m cable and the kit's RCA cable was 6m.

I intended to mount the amplifier longways but with the wiring installed, it was not going to fit without stressing the connections. Luckily for me, it was possible to mount it sideways but was going to be a tight fit.

There is an OEM hose and brace that prevented the amplifer sitting flat so I got aroud this by using 2 MDF mounting boards and cutting a corner "notch" out of the lower board to prevent crimping the OEM hose and clear the OEM brace.

There are three nuts on the driver's side chassis - I needed to cut a notch in the MDF mounting boards for the front notch to allow them to fit. This notch has the benefit of keeping the amplifier from sliding back and forward too.

I glued a rubber mat on the bottom MDF board to absorb vibration and help prevent it from sliding.

The amplifier is now wedged in tightly and the amplifier does not contact the chassis at all.

The door speaker wiring was a bit of a hack since the NB uses a harness to connect the door speakers rather than just passing the speaker wires through a door loom. Some guys simply wire their speakers to the existing harness at the Head Unit but I didn't want to go from 16 gauge wire to whatever the lower-specced OEM wiring is and it's hard enough as it is fitting my Pioneer FH-P80BT in as it is. I didn't want to drill new holes into the chassis so passed the wires through a gap in the door stop and they fit between the door trim. I made sure that the speaker wire was not crimped when the door was closed and that it remains contained behind the door waterproofing rubber.

The speaker wire was routed under the trim behind the driver and passenger side respectively and under the door trim. The passenger's side has a plastic hose that was "empty" so I threaded the wire through it. The driver's side has a wiring loom that I thought I'd use. After cutting the tape along it to fit the speaker wire into it, I found it almost impossible to insert the speaker wire along its full length so removed it, retaped the loom, and wired the speaker cable underneath it.

After the install, I fired up the stereo and got NOTHING!!!

I immediately googled amplifier install problems and figured that it MUST be a grounding issue so pulled everything apart and tested all fuses and wiring. NADA!

Next I hooked up a portable radio to the amplifier and everything worked perfectly?

I reconnected the Head Unit and tried to see if there was a menu setting to force it to use the RCA output instead of the harness output but found nothing. The manual didn't mention anything about this either.

I then figured that there must be a hardware switch on the head unit to force it use RCA output so pulled it out and found nothing! The manual didn't mention anything about this either.

Since the Head Unit was out, I hooked the portable radio up to the RCA connectors and heard NOTHING!

I then hooked the amplifier wiring kit's RCA cable up to the Head Unit and amplifier and everything worked perfectly!

It was that damn, F*****G RCA "lying around" cable that was problem, which is probably why it was spare in the first place!

I bought an overpriced 3m RCA cable from "Hardly Normal" since they were the only ones I could find who sold RCA cables approximately 2.5M long, and fitted it.

So was it all worth it?

HELL YEAH!

The output of my 6.5" crossovers really blew me away when I first heard them in the car. The car really pumps now and there's no need for a subwoofer since the doors really thump now with medium volume levels. I took the car on a trip to Mt Nebo and Mt Glorious on Saturday, then some highway driving, all with the top down, and the sound was fantastic where previously it would have gotten drowned out.

[Old Dude]

Good job Lokiel,
Glad your happy with the finished product, was it expensive?
cheers
Dale

[Lokiel]

The Pioneer Pioneer FH-P80BT Head Unit was about $600 (see viewtopic.php?f=55&t=38070 for details and slideshow of installation) - I think it looks great without being gaudy and almost looks OEM.
The JL Audio ZR650CSI 6" component speakers were $800 (I want great speakers and these were recommended on this forum somewhere),
The JVC KS-AX3002 Amplifier was $150 ons special from Repco at Xmas time.
The amplifier wiring kit was $45 on special from Repco at Xmas time.

So yes, it was expensive but it sounds fantastic and there's no need for an amplifier. Now, even with the top down on the freeway , the music doesn't get drowned out.

It's all quite stealthy too and doesn't take up any available bootspace so I'm quite happy on all fronts.

[Jeo]

Very clean install

You may run into problems regarding ventilation with it completely covered up like that. However I leave a giant kit bag directly on top of my amp almost all of the time and haven't had any concerns, just something I've been told to watch out for.

[Lokiel]

There is quite a bit of clearance above the amp itself and there is about a 3 cm gap between the top of the boot trim and the top of the boot so any hot air will flood out into the boot.

The amp itself runs quite cool compared to amps I've had in the past so I don't think that there will be any heating issues.

I was worried about heat initially and didn't want to mount it in the boot because I didn't like the idea of a long trip with bags siting on top of the amp.

[Wuey]

Saved for future reference, and thanks for sharing Lokiel. Great pics and instruction!

[Lokiel]

Here's some other "stuff" you may want to bookmark for future reference:

My Head Unit install:
viewtopic.php?f=55&t=38070

Here's a good thread on the Nautilus/Stebel Air Horn if you decide to upgrade your OEM Chihuahua horn:
viewtopic.php?f=55&t=30505
(my contribution is on page 6, including photobucket gallery link)

[Wuey]

Thanks again Lokiel. I like the idea of the cubby tray under the Sony single-din unit which is similar to my NA setup although the Pioneer double-din unit looks much more neater, like a factory job.

[djkinney]

HELLO!

I just did this same install on an NC, BUT when it was done, the woofers in the door just mumble and shuffle and gurgle. Something is seriously wrong. What could it be? Did it just "work" with you once you got it going, or did you have to play with the gain on the amp?

Thanks,

DJ

[Lokiel]

I had several issues with my installation so tried a lot of different things - it didn't "just work". I suspect your problem requires something more than fiddling with the amp's gain controls.

Have you connected the Head Unit's "remote" wire to the amplifier? If not, the amp will not function.

Have you tried connecting an iPod/portable radio to the amplifier and trying that? You'll need a line-out (for iPod/radio) to RCA (for amplifier) connector to do this. This was how I knew that the RCA cable I was using originally was stuffed since the portable radio worked fine with the amp and car speakers so it had to be the RCA cable or the Head Unit. Using the wiring kit's original RCA cable worked so I knew it was the RCA cable.

Grounding is a common issue with amplifiers. Is it possible you've pinched a wire or one of the connectors is unintentionally grounded to the chassis?

You should approach this problem on a component basis.

Start at one end, either the Head Unit or a speaker, test that works on its own by directly connecting an output or input source(eg. Head Unit+portable speaker or iPod+Car Speaker.

If it does, move down the component chain and include it in the test (eg. Head Unit+RCA cable+portable speaker or iPod+Amp Speaker Wire + Car Speaker).

Next try Head Unit+RCA cable+amplifier+portable speaker etc.

That's the most logical approach to the problem.

[djkinney]

Thanks for your reply. All of that's been done already. I have sound from the speakers. The system works. It's just the woofers in the doors that are sounding "blown out".

A guy from Critchfield suggested that I am overpowering the stock speakers.

He said that at 65 watts per channel it might be a whole lot more than the stock speakers can take.

Are you using stock speakers?

DJ

[Lokiel]

No, I'm using JL Audio ZR650CSI 6" component speakers which can take a lot of power (see http://www.ryda.com.au/JL-Audio-ZR650CS ... 650csi.htm) and were recommended here on these forums.

If you're using OEM speakers or low-end speakers, I don't doubt what Crutchfield is saying. One of the reasons I picked this amp was that it matched my speakers quite well.

[Jeo]

Tell the guy from Crutchfield to stop spreading internet rumours. The rms wattage to a speaker can not overpower it, only the idiot attached to the volume knob can. How you damage speakers is by pushing them so far that they physically hit the back of the driver and start 'clipping'. The amount of power an amplifier can supply has nothing to do with that.

[Shambler]

Hi there,
I'm looking to do this to my NB, but I'm unable to find this amplifier in Australia. Are you aware of any other amps that would fit into this space?

Thanks,
Sam

[Lokiel]

Hi there,
I'm looking to do this to my NB, but I'm unable to find this amplifier in Australia. Are you aware of any other amps that would fit into this space?

Thanks,
Sam

I believe Repco still stock these.

See Ryda also: http://www.ryda.com.au/JVC-KS-AX3002-2- ... ax3002.htm