Installing an amp... No head unit can compete!

[Trueweb]

If you really want to do car audio right you install an amplifier. There is no head unit that I know of that can compete with any amplifier. A clean 20W amp will outperform a 50W head unit any day. Just compare them by weight. Most 20W amps weigh more than head units and they don’t have an LCD display, or motors to squeeze in around the amplifier parts.

I searched long and hard for an amplifier that would fit. You have to get something that is less than 7” across and 1-7/8” high. The longer you have to go the less tall it can be. So, a good maximum size is about 6” wide x 1-7/8” high x 10” long. I found the Lanzar OptiDrive 4X400D which is a 100Wx4 amplifier that performs quite well from what the reviews say. The specs aren’t bad and CEA2006 ratings are even higher than the manufacturer’s specs, which is a good thing. It also fits, which is an even better thing! Now that it’s installed I can tell you it has serious potential. It runs clean to full volume and you can hear the speaker bottoming out before there is any distortion from the amplifier. I need to find bigger/better speakers!

[Trueweb]

Following are some images of my “amateur” install and some notes regarding things I had to do to make it work.

Below you will see how I routed the power out of the trunk into the engine compartment through a grommet.


Next, I just followed the main harness to the firewall behind the driver seat.


This is just a shot pulled back so you can see both ends of the wire.


Here is where I came through the firewall. There is a grommet just behind the driver seat belt reel that they main harness comes through. To remove the plastic panel behind the seats you need to remove the back part of the console, the “cup holder” and the four screws and plugs below the rear glass (be careful they are plastic and can strip easily and don’t bend up the plugs pull them very gently). You will also need to remove the driver seat belt top loop from the roll bar. I don’t have a good image of that. Of course you also need to have both seats out of the car at this time. There are a couple good posts on how to do this. Once the screws and seat belt loop are out slowly pry the plastic out from the driver side be careful not to pull off the rubber trim glued to the body work. Once the drive side is loose the whole thing just slips out easy. Unplug the “dome” light and remove. One the panel is out you will have to contest with a large piece of foam. Carefully pry it from behind the driver seat belt mechanism being careful not to tear it, just go slowly. Once it’s out you can bend it out of the way and see the harness and grommet as they appear in the image below.


Here is another shot, pulled back a bit so you can see the final result with the power cable under the foam and carpet. I was actually able to use the same loops that carry the harness to route and hold my power cable under the rear deck.


Following are a few shots of getting the speaker wire and RCA’s from the head unit to the amplifier. You’ll notice I used duct tape and carefully taped all the wires as flat as possible against the inner rocker. The carpet is just held on by Velcro, if you don’t have the touring pack I have no idea how you’ll hide these wires…



Here is the real trick, getting the wires from the sill to the head unit. I spent a lot of time on my back under the dash looking at an impenetrable sheet of aluminum. If you wind the wires back toward the sill cover and tie them up to the main harness you can sneak in behind the blank plate above the coin holder on the passenger side. There is plenty of room back there and the plate is really easy to remove. Just two screws near the top back in the coin area. I don’t have any good pictures of the routing to the deck, but here goes… Once the plate is out you can look into the dash and see the right front speaker. You will see an angled aluminum bracket to the left of the speaker. Straighten out a coat hangar and bend it into a big curve. Feed it in just above that angled bracket (the head unit should be removed at this point, use the special tools in the box for this) and fish it into the head unit space. If you stick your hand in the head unit hole you will eventually feel the coat hanger as you twist it around. With one end of the coat hangar sticking out the blank plate area and the other sticking out the head unit space, you can tape one wire at a time to the end of the coat hangar and carefully pull them through. Repeat his for each wire. There is plenty of room behind the head unit to hide extra wires… Oh yeah, don’t forget the antenna when you hook things back up.

[Trueweb]

Here is the amp in place. It is held with two strips of Velcro that run pretty much the entire length of the amp, I pulled on it and twisted it, it’s not going anywhere. Especially once the seat is in place. You will notice I had to mount it a little higher than the rear deck. This is due to the length. Any lower and it’s too high to fit between the seat and the rear panel. Be careful to align it so it will fit between the “rails” molded into the seat.


A little closer with the wires cleaned up some.


Another angle, you can see how the side carpet hides the wires nicely.


Here is what you can see with the door open and the seat in place. A little black wire loom and this thing will just disappear.


With the door closed, it’s virtually gone!


From the driver side, with the seat all the way up. This is the best angle to see it from. If the seat is back (as though you just got out of the car) the amp is very hard to see. Another nice thing about this location is that with a little effort I can actually adjust the settings on the amp from behind the seat. A flashlight is needed as is a flexible arm. Again, some wire loom would make this thing just disappear.

[Trueweb]

Note: I just ordered a Sony XM-2040 Amp off eBay, this will fit even better (tiny little amp), but the Lanzar is rocking right now and I’m going to leave it for the time being. If you really want a completely hidden install I would recommend looking for a Sony XM-2040 (4x20W RMS) amp, very clean and 2-ohm stable. You could also use 2 XM-2020 amps (they are about the size of a deck of cards), these have the same specs as the XM-2040 but they are only 2-channels. If you don’t mind losing the fader you can run one XM-2020 at 2-ohms and run all your speakers at 35W RMS. I used to know a guy that competed in the ‘under 50 watt class’ with that exact setup and he cleaned up at every competition, of course not many people have less than 50W these days. Don’t purchase either of these amps if they don’t include the wiring harness.

Good luck!

[jeff8875]

Nice write up... good pictures too... I figure I will tell you since no one else has!

I have been playing with that aluminum too... looking to where I should run the wires... I ran them up through the middle and under the section where the e-brake is. I found a hole in the underside of the dash but I can't tell where it is going to.

Also how did you get the power wire in the the cabin... did you go from the cabin to engine compartment or engine compartment into the cabin... I am having trouble because of the aircleaner box being in the way and gave up till the morrow

Edit: Also I dont see your power turn on wire being run with your speaker and rca cables... did you run it to the cigarette lighter? That is what I was thinking but I have to test and see if it is alway on or not.
Last, how did you velcro it? did you cut away part of the carpet?

[MattG]

Beautiful work! Nicely done.

[Trueweb]

Thanks! I was wondering if anyone had even noticed

I routed the power wire from the trunk to the cabin. I started in the trunk and used a screw driver to lift the inside lip of the grommet. I was able to feed the wire through with the screw driver tip. I pulled all the excess wire through into the engine compartment except for a few feet including the fuse block on the power wire. Then, from the passenger compartment I punched a hole in the grommet behind the seat belt mechanism using a coat hangar (you have to punch the hole because the wire harness is taped to the grommet on the engine side so you can't feed through the inner seal of the grommet). I fed the coat hangar until I could feel it below the air box. I pulled enough coat hangar through to tape the power wire to the end of the coat hangar. I then pulled the coat hangar and the wire through the hole I made in the grommet. Then I pulled the power wire the rest of the way into the passenger compartment.

I grounded the system on the front left passenger seat bolt by feeding the ground cable through the square tube, it worked out really nicely. I'll try to get a picture.

The Rockford Fosgate RCA wires I purchased had a remote turn on wire molded in between the right and left channel leads. I just used the one they included. The blue wire you see in the picture is connected to the remote power lead in the RCA cables. I believe if you run your remote to the lighter it will always see power and the amp will always be on.

I ran two strips of velcro vertically on the amp (the long direction, 2 strips of about 7 or so inches worth) I only used the hook portion of the velcro. I'm using the carpet as the loop portion. In other words, I just stuck the amp to the carpet. As you can see from the pictures it holds quite nicely.

I am now working on a speaker box for the footwell. I'll post some pictures and thoughts soon.

[Trueweb]

Here are some details of how I ran the ground cable...

Through the rail in the back of the seat


And bolted under the bolt in the front of the seat


This made it very easy to keep in place while bolting down and the bolt under the front left of the passenger seat is probably the easiest one to get to.

[dbisbee]

Very nice documentation I am getting ready to take the plunge. I need to return the $375 of what I got talked into today at Stereo 1. Los Angeles has car stereo stores every block and I listened to this guy after being not impressed with three other stores. But after I got home with a handfull of capictors and some outdated Cerwin Vega speakers. I installed one side in the front and rear without the amp that I also bought and they sounded worse than the stock speakers. He said he will give me store credit and maybe I can purchase what I went there for which was some JL Audio speakers.

I got a Clarion Amp that I was going to try and install under the dash but I like what you did so much better that leaves the underside of the dash virgin for a subwoofer if somebody would get that one done.

I looked and could not find that Sony 2040 amp on eBay and Sony site. Anybody else got listings for Amps that will fit behind the Passenger seat?

Thanks for all the pictures and information,

[Trueweb]

Originally Posted by dbisbee

Very nice documentation I am getting ready to take the plunge. I need to return the $375 of what I got talked into today at Stereo 1. Los Angeles has car stereo stores every block and I listened to this guy after being not impressed with three other stores. But after I got home with a handfull of capictors and some outdated Cerwin Vega speakers. I installed one side in the front and rear without the amp that I also bought and they sounded worse than the stock speakers. He said he will give me store credit and maybe I can purchase what I went there for which was some JL Audio speakers.

I got a Clarion Amp that I was going to try and install under the dash but I like what you did so much better that leaves the underside of the dash virgin for a subwoofer if somebody would get that one done.

I looked and could not find that Sony 2040 amp on eBay and Sony site. Anybody else got listings for Amps that will fit behind the Passenger seat?

Thanks for all the pictures and information,

You've got to keep watching for those small Sony amps. The one I just bought is listed here... Sony Amp on Ebay (I was really fortunate). Here is a XM-2020 that is currently active, this would be a good buy if you don't care about fading front and rear. XM-2020 on ebay It even has all the harness.

I'm working on the subwoofer idea, check out the thread I just started related to getting a sub installed.

Good luck!

[jeff8875]

I think thats really cool how you grounded the amp....why didnt you just ground it to the rear of the seat?

[Trueweb]

Originally Posted by jeff8875

I think thats really cool how you grounded the amp....why didnt you just ground it to the rear of the seat?

I can barely get the bolts in the rear of the seat without trying to thread them through a ring connected to a wire. This way the wire is still hidden and it was really easy to get the bolt in place.

[Lotus F1]

Originally Posted by MyElise

I remember reading somewhere about a new type of amp that uses a different kind of output circuit that is low in heat and therefore doen't require a big heat sink?

Should be much smaller and lighter (and more expensive).

Anybody know about this?

Digital Amplifiers are what you are refering to. My Panasonic head unit has one of these digital amplifiers and it provides much more power then most conventional head unit amps

[Hollywood]

you could have run the wires up the center by the shifter and had any wires showing anywhere. i ran my up the middle and then over to the right side through the little hole under the dash like you.

[jeff8875]

Originally Posted by Hollywood

you could have run the wires up the center by the shifter and had any wires showing anywhere. i ran my up the middle and then over to the right side through the little hole under the dash like you.

This is what I just did... (break time so sweat can dry), man that space is small by the footwell... I am not a huge guy either... about 190, I was suprised at how much I could NOT fit.

[Trueweb]

Originally Posted by Hollywood

you could have run the wires up the center by the shifter and had any wires showing anywhere. i ran my up the middle and then over to the right side through the little hole under the dash like you.

True!

I could have also kept the wires hidden by just coming up through at the floor instead of routing them into the rear deck cover. I wasn't sure how the amp was going to be mounted at the time so I pulled a lot of excess and that method worked to keep it all in control.

I think you're pretty safe either way. I did notice that if you pull them through the center there is a chance you can see them through the holes in the forward aluminum structure. I didn't take the console apart so I don't know if there is a way to route underneath the harness or not.

[Hollywood]

there is alot of room in the tunnel. i ran some think wires under the stock wires that are in there. plenty of room.

[BMJM100]

Question, do you have any motor noise?? Nice job on running the cables. I see you wire tied together the speakers/RCA cables with the power battery cable. Noise can jump from battery cable to your signal cables either your RCA's or speakers wires.

One more helpful note, aluminum is note a good ground. Lotus uses a common ground that is not connected to the aluminum. They do however add grounding cables or braided lines to help ground them.

I'm not here to criticize, but to help my fellow Loti owners. There is a lot one can see from photos.

If you don't have motor noise then your all set.

Other than that it looks very well thought out and looks great!!

Bruce (18yrs at high end car electronics business will do this)
(Please don't take this the wrong way.)

[rob13572468]

one more thing to add...

anytime that you run wires in the engine compartment or even in the front exterior sections you should at be using flex loom to shield the wire from heat and chemicals (i.e. grease, oil, gasoline, etc.). its not absolutely necessary but you may want to do all the wires this way on the interior as well. also it wouldnt hurt to use the friction harness tape so that they look all nice like the stock harness. heres some shots from a client's elise that i am wiring right now to give you an idea of how all of the wiring will look.

[Trueweb]

No electric noise at all, taken the right way!

I did experience a hiss during fine tuning, but I discovered I had my input levels set too high for the pre-amps, the flick of a switch fixed that. My power wire runs to the back and the speaker wires run to the front so they are really only tied together for about 6".

You are 100% correct about the cable routing. Since I have never actually had a problem with this I tend to be a little lax about it. On the other hand I have struggled numerous times with grounding issues. In a lot of cars I've wired I get an electric whine when the head unit and amp are not grounded at the same point. I'm not getting this problem in the Elise currently.

I believe you are incorrect about grounding to aluminum. Wiring is typically made of copper or aluminum. You will also notice that the binding posts on most amps are made of aluminum. This is for a reason. Copper is more conductive than aluminum and aluminum is more conductive than steel. For this reason it's actually better to ground to the aluminum. Perhaps I'm missing something, I wouldn't mind being corrected.

One more thing, a question for you. My expertise is actually in computers. When running data cables you always want to run them as far away from power as possible and when you need to run near power the preferred method is to run perpendicular to the power cable. This keeps the wire as far out of the electric field around the power cable as possible. Does this same strategy hold true for audio?

Thanks for the comments. My goal in posting all the stuff I have is to help others, so anything that helps is appreciated.

Originally Posted by BMJM100

Question, do you have any motor noise?? Nice job on running the cables. I see you wire tied together the speakers/RCA cables with the power battery cable. Noise can jump from battery cable to your signal cables either your RCA's or speakers wires.

One more helpful note, aluminum is note a good ground. Lotus uses a common ground that is not connected to the aluminum. They do however add grounding cables or braided lines to help ground them.

I'm not here to criticize, but to help my fellow Loti owners. There is a lot one can see from photos.

If you don't have motor noise then your all set.

Other than that it looks very well thought out and looks great!!

Bruce (18yrs at high end car electronics business will do this)
(Please don't take this the wrong way.)