HOW TO: Install an external amp with BOSE HU (Pre-Amps)

Vord

Member
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99 Emerald Mica Miata LS
after a few people have asked for this, I decided to do a little how to.

Unfortunately, I don't have time to take out my glove compartment and all that s***, but I think there is already a how to on this. I will give as detailed a description when that stuff comes along. There is also wiring diagrams around, but I will post which colors I used for everything.

If anyone has any questions, then ask away!

Also, when taking apart anything please be gentle. I am not responsible if you break your trim pieces or anything like that.


Step 1: headunit removal+ Glove compartment

First thing we need to do is take out the trim piece above the glove compartment. It is held in with clips most of the way and then a clip that slides in side-ways. THe picture shows about where your hand should pull back to take it apart. If it is the first time, the trim piece can be a little stiff so don't worry too much if its hard to pull out. A bit of wiggling can help.

trim-piece.jpg



Next, we should take out the headunit. there are two screws to take out, circled here:

S73F0494-1.jpg



Once the screws are out, we need to remove the headunit. This can be a bit tricky. DOn't pull any of the plastics that are there, they can break and they are not that durable. Instead, as my picture shows, there is a metal piece behind the screw holes that you can use a finger (or two) to grab and wiggle and pull. A slight upward motion can help. Here is the picture:

S73F0493-1.jpg



Once the headunit is out, the harness can be removed and anything that may need to be done can be done. The reason we need to remove the Headunit is so that we can get access to the remote wire (which is used to turn on and off the amp). Specifically, it is the blue wire in the harness. I don't suggest you cut it, rather splice it. This can be tricky, but its nicer. I also suggest you solder it on there and get some electric tape or heatshrink for any exposed wiring. Here is a picture of my blue remote wire going to the amp and it is surrounded by electric tape.

Remotewire.jpg



Now we need to take out the glove compartment. Unfortunately, I am too busy to take mine out, but pretty much you need to take out the kick panel and side trim and the two screws shown here. After that its a bit of wiggling and pulling. I don't exactly remember if there is anything extra.

S73F0495-1.jpg



*****Step 2: The power wire and firewall

Pretty simple and self explanatory. Get yourself a proper gauge wire and fuse and all that simple s***. Then cut out a hole in the firewall (which can be found at the leftside of the car, when facing it from the front, it is behind the aluminum heat absorbtion stuff). Run that wire through the firewall and grab it from the inside. Here is my firewall picture:

S73F0500-1.jpg


Take the wire that is now coming from the firewall and the remote wire and run them under the trim pieces, this can get tricky if you are using large gauge wiring, but its all pretty simple.

Here is the beginning of mine:

S73F0496-1.jpg




******Step 3: The low-level input from the bose amp

Bose amp is kind of a b****, there is no leway on the wires and if you want to keep the same speakers it can be a b**** to solder them back together.
None the less, it is what I did.

Although you can use practically any color from the input set, I used the White W/ blue stripes and White w/ grey stripes. Just to be clear here, Its out of the BLUE harness. This is one for the small bose sub. If you take your seat and move it all the way to the back you will see the harness I am talking about.

Here is a picture of my black and white spliced wires. Sorry if the pictures are fuzy:

S73F0497-2.jpg



Now run those wires under the left side trim pieces and we are almost done.

******Step 4: where do the wires come out?


Hopefully the pictures are self-explantory, I ran them behind the trim pieces all the way, then stuck my hand in there or a long hooked clothes hanger and grabbed them.

Low-Level lines:

S73F0501-1.jpg



Power and Remote lines:

S73F0502-1.jpg



Thats about it. Sorry for the lack of detail, its just that Its a 2-3 hour job to take it out and put it back together and I am taking summer classes. If anyone has questions or suggestions, message me and I will respond.

Next Up: Pictures of the interior amber LEDS and a bit of LED research.
 
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which wire is the remote wire coming out of the head unit which i can tap into?
i dont see a blue wire, only a blue/yellow wire


Do you have the Bose headunit?

If you do, make sure you are looking at the right harness. One at the bottom right if you are looking at the top of the headunit when its in the dash.

If you still can't figure it out, take a picture of the harness you are using and I will see what i can do. I know I got a pinout of the HU somewere.

make sure you have the Bose HU
 
Ok, yea I have the Bose HU so i should see what you see. I plan finishing it up tomorrow or Wed. so i'll keep you posted. i really appreciate the information, how to guide, and quick responses as well. You've definitely made this install a much easier task.
 
Doesn't anyone make an adapter that plugs directly into it so that I don't have to splice wires? I haven't hacked a harness in a loooooooong time and don't want to start doing that crap again on this car...
 
Doesn't anyone make an adapter that plugs directly into it so that I don't have to splice wires? I haven't hacked a harness in a loooooooong time and don't want to start doing that crap again on this car...

excuse me if I have to chuckle a bit on this, but we are using a stock headunit. I don't think they are going to make a harness for 1 remote wire out of a Stock Item to sell to us. I don't even know how you would go about doing that without making a female-to-male end of our harness with an extra remote wire coming out.
 
**** me for not having the bose headunit. I am not sure how different it would be to do this amp install on the regular deck
 
**** me for not having the bose headunit. I am not sure how different it would be to do this amp install on the regular deck

Very. The regular has no pre-amp output. You will need to get a new headunit or actually go through the circuitry in the stock headunit and do it.


Other option would be to try and buy the GT bose HU and replace yours, but I don't know how well taht will work. unless you are planning to replace all your speakers at the same time.
 
so the low level wires are they going into a line converter to rca or are they just going to be rca ends sodered onto the ends and plugged into the amp?
 
excuse me if I have to chuckle a bit on this, but we are using a stock headunit. I don't think they are going to make a harness for 1 remote wire out of a Stock Item to sell to us. I don't even know how you would go about doing that without making a female-to-male end of our harness with an extra remote wire coming out.

My Silverado had an adapter made by PAC to plug directly into the low level harness of it's Bose stereo. I didn't have to cut any wires, not just the remote wire, the signal wires too. Aren't you having to tap into the signal wires somewhere??? That means cutting/splicing, which I'm not going to do.

Most Bose systems are still to high of power for the low level inputs on most amps with RCA inputs. You need to run through a converter or risk blowing up the input side of your amp/s.
 
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My Silverado had an adapter made by PAC to plug directly into the low level harness of it's Bose stereo. I didn't have to cut any wires, not just the remote wire, the signal wires too. Aren't you having to tap into the signal wires somewhere??? That means cutting/splicing, which I'm not going to do.

Most Bose systems are still to high of power for the low level inputs on most amps with RCA inputs. You need to run through a converter or risk blowing up the input side of your amp/s.


unless bose is running some ridiculously high low-level, i doubt it. most amps can accept a low level signal at 8v, which is plenty enough. if you have concerns, you can get a volt meter and check.

If you don't want to splice, then its up to you man. If there is a harness, I have never heard or found it, but that would be nice. As for the silverado, I am pretty sure there is alot more silverados than the speed 3 and therefor alot more demand for luxury items and clean setups.
 
Question: what kind of wire do you connect to the bose amp and how do you connect that to the RCA ends?

Thanks,

Paul
08.5 MS3 (true red); 1998 Panoz AIV
 
pretty much any low-level acceptable wire. anything from 18-12 gauge is fine. 16-14 is probably ideal.

You will need to create your own RCA end. If you go to Radio shack, they have them in pairs with instructions on how to connect them.
 
yeap, you will need 2 of them. one for the Left and one for the right.

so splice the two positives of the RCA to the positive on the amp and the 2 negatives to the negative on the amp.
 
I installed my aftermarket amp without going behind the head unit...the BOSE amp is right under the driver's seat & it is much easier running & hiding the wires from there...if anyone is interested I will post pics.
 
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