CoreY2K1

i'm about to install a V12 amp in my GS4 and was just curious to know if anyone has used the rear wall of the trunk, directly behind the rear seats, to mount their amps...

this seems like a good location to maximize trunk space. anyone do this with success? how did you secure the unit? thanks...

Overtaxed

I have. But I didn't do the installation myself, and I wasn't around when they mounted the amp.

http://www.greendale.se/lexus/sound/sound-trunk.JPG
http://www.greendale.se/lexus/sound/sound-boxamp.JPG

Don't know if it's any help, but this is how it looks behind the back seat:
http://www.greendale.se/lexus/sound/sound-rearseat.JPG

GSAristo

I was able to mount 2 amps in that space, and then another two on that raised area just below. I made an amp rack, using 2 pieces of 1/2inch MDF, some L brackets, wood screws and some trunk liner carpet. Then I attached the amp rack to the car, via some long screws going through the stock trunk trim to a couple of holes in the diagonal metal braces just between the trunk trim and the rear seat. After you remove the rear seat, look under the black rubber panel (as seen in the left side of Overtaxed's 3rd picture). Attached are pics of the rack and the amps mounted on it.

CoreY2K1

thanks guys. well, it looks like it will work for what i want to do...

regarding the sub, i was planning on creating a sealed box for a single 10" and then mounting it so that it is suspended below the stock hole. then, carpet the box to match so it looks nice etc... any thoughts on that setup?

just trying to save as much trunk floor space as possible...

Overtaxed

About saving trunk space.

With my install (see above) I can just unplug the connector to the amp and lift out the box when I need the full trunk space (which is like once every other year).

tmilne

Allan...

Which sub is that? Did it fit the stock hole?

GSAristo

Tmilne,

That's a Focal 13 inch subwoofer. Due to it's size, it did not fit in the stock 10 inch hole. I had to make a baffle and bolted the sub to it, then I bolted the whole thing under the rear deck (using stock holes in the rear deck for the bolts). The baffle was made up of two pieces of 1 inch MDF, with Cascade Audio sound dampening sandwiched in between to keep the sub vibrations from being transferred to the rear deck. Even though the sub was not designed for a free-air configuration, it goes pretty low and is dynamic enough for various types of music. Though right now, I think I could use more power to it. ;-)

GSAristo

tmilne,

Here's a collage of pics (going clockwise) of the baffle, a test fit of the baffle to the rear deck (note the silver bolts), the sub mounted on the baffle, and the baffle and sub mounted to the rear deck.

Mean Gene

Allan - I was told by a Focal tech that their SPL subs R designed for use in ported applications - I was thinking of replacing my HX2's with a pair of the 13" woofers, at least until I found out the cost of them!!:eek: Additionally, he told me that I'd need more power than the Power 1100a2 would provide to make it worth the swap, plus they don't work well in sealed enclosures, or so he said. U can use any sub in any configuration but they work best in the enclosures ( or lack of ) that they are specifically designed for. Even saw a pic of Shaq's MB with that sub firing into a fiberglass bandpass enclosure!! Really like the looks of the multiple magnet design & hear that it works well for SPL. Any thoughts?

GSAristo

Hi Mean Gene,

Lack of power would be an issue. I have that problem right now, my Orion HCCA 225 bridged is rated at 100watts RMS. I'm feeding the amp 14.4 volts so I should be getting around 125watts at least, due to its unregulated power supply. Unfortunately, this is not enough power. I'm thinking of using a PPI PowerClass amp. My stereo shop guru recommends that I go with 2 PPI PowerClass amps (each has 4 channels x 100watts each (or 2channels bridged x 400 watts each)). He says that my sub will perform better, since the more powerfull amp will be able to control it better. Unfortunately, I'll have swap out my Orion Reds. :-(

As far as your Power 1100a2, yes I'd agree with the Tech, 275watts RMS into a 4ohm Focal sub is not enough. Both channels bridged though at 1100watts RMS would be adequate (hehehe), though that's at a 4ohm load. If Focal makes a dual voice coil sub, you could parallel the voice coils (provided they're 4ohms each - to make 2ohms) then run each sub off each amp channel - so then you get 550watts RMS to each sub! I'll have to check though if Focal makes such a sub.

In regards to the pricing, I know what you mean, Focal speakers are rather pricey. Luckily, I've got a hookup on Focal speakers (kind of like a sponsorship - since I take my car to shows and promote the shop). Send me a "PM" for the models you want and I'll get you some really good prices. I think that's the least I could do for you. BTW, thanks for all of your advice last year while I was putting my system together in my GS. You (and Percy) were a great help! I just wish you could see (and hear!) it now.

CoreY2K1

Allan,

Your 13" sub fires into the stock 10" hole, correct? I was curious to know if that set up caused any sound problems... I'm thinking of going with a 12" there, with a suspended, sealed box. It just occurred to me that firing a sub through a smaller hole might bring up some issues, although you seem pretty happy with your set up...

Mean Gene

Allan - I may hit ya up on those sub prices later. Just need to go to Focal's website & get some more specs on those 13" subs. Another idea concerning power would be to parallel two of the the 4 ohm SVC's & then run the amp bridged ( 1 ohm load!! ). I've run RF's in this impedance before & with no trouble as long as I kept good voltage to it ( may consider an Accuvolt ) & kept it cool. The last parameter is my current ( HA-HA!! concern as it gets mighty hot in the trunk of a black car here in Louisiana during the summer & I have had the 1100a2 S/D in thermal protection mode before when I was really jamming it! Gonna try to tap into the rear HVAC ducting if I can but not too sure about that possibility - talked to Percy & Brad about it last year & just blew it off as I'd decided to consider selling the GS & still may. Will contact U later for Focal pricing if I go that route & thanks for the offer!!

GSAristo

CoreY2K1, I too was concerned about that same issue. My friend had the same setup already in his GS, so I was lucky to be able to listen to it before I did it in my car. I think that if you make sure that the sub has enough clearance so that it does not hit the deck, then it should be fine. That's why I have a 2.5 inch baffle. One other thought is that with the various sub configurations that I've seen in the GS (be it free air, sealed, ported, or even bandpass), more often than not, they used the stock 10 inch hole to vent the sub frequencies to the passenger compartment.


Mean Gene, yes, please let me know if you need any Focal (or other car stereo) equipment. I can get other brands as well. I personally hope you don't sell your GS. If you do, the person who buys it will have really lucked out. Wow, your amp can handle a 1 ohm load bridged?! That's pretty impressive. I would highly recommend that you do go the Accuvolt route if you do. I'm using an Accuvolt FR-1500 in my system. My Orion amps love the rock solid voltage at 14.4 volts!