[boardboy330]

I have searched, over and over. I found several topics on this subject but I am still having issues. I found the pictures and diagrams. My problem is - the amp isn't where the picture shows. I know I have one, because sound is coming out of the speakers through a preout connection.

Here is one of the links to those threads:

http://www.benzworld.org/forums/w163-m-class/1454532-2000-ml320-bose-amp-2.html


The picture is upside down - but looking in that direction there is no amp. It wouldn't normally be an issue - but I want to tap in to the wires there. I bought a new amp to install in place to power the speakers.

I read in one thread there were multiple locations for the amp to be installed. Where were the other locations?


Also found - someone installed (half assed my I add) a lo-jack type system in the truck. It will be removed during this install.


EDIT: The reason I am getting in to this is I think two fold. I installed Boston Acoustic component speakers a few years ago. The sound quality is amazing, but the sound has always been lower than I wanted. When you turn the volume to max - it should be TOO loud to listen to. Turning it to max gets normal listening volume. I think it's a mismatch of impedance and lower than normal input voltage. The pioneer installed puts out a 2V signal instead of 4-6V others do. Either way, it's too quiet for me and I want to drive it with a different amp.

 

[gotca]

...
I read in one thread there were multiple locations for the amp to be installed. Where were the other locations?
...

I know mine is under the driver seat.

 

[boardboy330]

I know mine is under the driver seat.

Should have added that info too. I have a bose subwoofer under the driver's seat and nothing under the passenger seat.

 

[art_arev]

Should have added that info too. I have a bose subwoofer under the driver's seat and nothing under the passenger seat.

Boardboy Hi
The link you have sent were the picture is upside down has the amp , but if you read the post properly you will see that he has changed the original position of the amp. The sub is under passenger seat as you said. You have found it!!!!
The amp is NOT behind the pedal!. After removing the cover (on top of the pedals) on the drivers side, lie down on your back and look up. You will see felt and some materials etc. Move the right side of the felt out of the way. At the far right ( high behind the cup holder) you will see the fins of the AMP

 

[art_arev]

Check out the pdf's. Look for A2/13. Dont worry that one of the pdf's says fiber optic ...... the amp location is the same. A2/13

 

[boardboy330]

I will check that out, thanks. I figured it would end up requiring removing the driver's seat from the vehicle. I'm 6'3"...so I will get it out and lay up under there.

I will check that thread out again, I def missed the part about him moving it.

 

[art_arev]

It will be a bit tight for you, but I dont think you really need to remove the seat. Push the seat back . I am sure you will be able to fit your upper body under the dash, while your lower body can stay outside of the car (through the door):thumbsup::thumbsup:. It will be there dont worry, you will find it as described.

 

[boardboy330]

It will be a bit tight for you, but I dont think you really need to remove the seat. Push the seat back . I am sure you will be able to fit your upper body under the dash, while your lower body can stay outside of the car (through the door):thumbsup::thumbsup:. It will be there dont worry, you will find it as described.

I will give it a try. I have a 54" chest...so...I'm not exactly a small guy. I tried getting my arms up in there to feel around last night and even that was difficult.

Thanks again for the help. I will let you know if I find it.

 

[RJV]

In my RHD car the amp is on the far right of the right foot well, above the accelerator pedal at about the cup holder level. One needs to peel away some white fluffy insulation to reveal the amp bolted to the firewall.

I can only assume its in the mirror opposite location in a LHD car, so on the far left of the left foot well above the foot brake pedal at about cup holder level.

There's definitely no need to take the seat out, it is too much work for the small benefit it will provide. Once you have laid your eyes on the amp you will be able to remove it by feel. There is only one bolt holding it (either 8mm or 10mm head from memory) to the fire wall, and with this bolt removed it flips out of its bracket and you can pull it down to pedal height and unplug the connector.

If you squat down next to your open driver door facing the rear of the car, place your left shoulder/elbow on the door sill and then slide into the foot well so that your back is on the floor mat and your legs are still out of the car (feet on the ground), you can actually get quite comfortable and work up under the dashboard. I'm 6'2", but I don't have a 54 inch chest !


My Bose subwoofer is under the passenger seat (left side of RHD car). I've yet to see a Bose amp under the seat - I do wonder if some members get the subwoofer confused with the amp.

 

[43sqd]

RJV is correct. The sub woofer is under driver's seat (RHD), not the amplifier.

 

[boardboy330]

I tried doing it with the seat in...no go.

I removed the seat and found the amp. Removed it and pulled the wires down to the drivers side footwell.

Will leaving the amp disconnected, cause the AM/FM amp not to work? Any other issues leaving it disconnected?

 

[RJV]

I tried doing it with the seat in...no go.

I removed the seat and found the amp. Removed it and pulled the wires down to the drivers side footwell.

Will leaving the amp disconnected, cause the AM/FM amp not to work? Any other issues leaving it disconnected?

I don't think leaving the Bose amp disconnected will impact the AM/FM amp or create any other issues. See the attached wiring diagram.

There are 23 wires connected to the Bose amp :

- 8 audio inputs (4 pairs for left and right, front and rear)
- 12 audio outputs (as above, and 2 pairs for the subwoofer)
- 1 power supply (red)
- 1 ground (tan)
- 1 wire to the AM/FM antenna (orange)

However, for the last wire above note from the diagram that A5 on the head unit, A1 on the Bose amp and C1 on the AM/FM amp (bottom of diagram) are all interconnected together (all orange). Unplugging the connector from the Bose amp should not impact the AM/FM amp - A5 will still be connected to C1.

 

[boardboy330]

OK, while I do not understand your reasoning - I will go with it lol.

I am jumping the ingoing and outgoing lines to basically send the signal from the headunit straight through to the speakers. I sincerely hope this resolves my issues and I won't need to install another amp.

 

[RJV]

The reason I am getting in to this is I think two fold. I installed Boston Acoustic component speakers a few years ago. The sound quality is amazing, but the sound has always been lower than I wanted. When you turn the volume to max - it should be TOO loud to listen to. Turning it to max gets normal listening volume. I think it's a mismatch of impedance and lower than normal input voltage. The pioneer installed puts out a 2V signal instead of 4-6V others do. Either way, it's too quiet for me and I want to drive it with a different amp.

If you jumper the Bose amp inputs to the outputs (i.e. effectively bypassing the amp), then you will just end up with the 2V signal from your Pioneer head driving your Boston Acoustic speakers. I don't see that this will give you any higher volume output than before, unless :

(a) the Bose amp was faulty, or
(b) you change from a line out level on the head to a speaker out level ... assuming your head unit gives you a choice.

I had overlooked that you had swapped the MB head for a Pioneer head. My comments in my previous post still apply, unless in fitting the Pioneer head you disconnected the AM/FM amp .... which is probably unlikely as you haven't mentioned that you have any AM/FM signal issues.

 

[art_arev]

Boardboy Hi
There is something you were/are doing wrong. There is no way bypassing the Bose will increase your volume. Or your wiring was incorrect or internal settings of the pioneer ( high gain/low gain) was set to low..... The Bose amp inspite of the size is quite powerfull. Your head unit drives 20-22 watts RMS power. The Bose gives much,much more. Check things properly.

 

[boardboy330]

If you jumper the Bose amp inputs to the outputs (i.e. effectively bypassing the amp), then you will just end up with the 2V signal from your Pioneer head driving your Boston Acoustic speakers. I don't see that this will give you any higher volume output than before, unless :

(a) the Bose amp was faulty, or
(b) you change from a line out level on the head to a speaker out level ... assuming your head unit gives you a choice.

I had overlooked that you had swapped the MB head for a Pioneer head. My comments in my previous post still apply, unless in fitting the Pioneer head you disconnected the AM/FM amp .... which is probably unlikely as you haven't mentioned that you have any AM/FM signal issues.

I am of the impression a combination of 2V Preout instead of 4-6V and Ohms not matching up correctly is causing the lower volumes.

I fully intended to install the speaker level instead. I wired up RCAs on the ends last night so I could plug and play on my harness.

 

[boardboy330]

Boardboy Hi
There is something you were/are doing wrong. There is no way bypassing the Bose will increase your volume. Or your wiring was incorrect or internal settings of the pioneer ( high gain/low gain) was set to low..... The Bose amp inspite of the size is quite powerfull. Your head unit drives 20-22 watts RMS power. The Bose gives much,much more. Check things properly.

Not sure what to say. My old Pioneer had the same issue and I swapped it for this new one. Not only have I had the issue, but others have shown the same problem. No other audio issues.

This is a step in resolving the problem. I want to jump the lines to check and see the output. If it's louder - it's a problem with the amp. I have two other amps I can use - but they are quite large.

 

[art_arev]

I am using a JVC head with 2v preouts into the bose amp and a sub amp with 12"sub. Its crazy loud and clean. I wont be able to open up the volume half way. I am using Bose speakers. You have changed the speakers to 4 ohm. The amp is 2ohm. But still you must have plenty volume. Changing the speakers from 2ohm to 4 ohm doesnt mean you will lose the volume by half. If your wiring is correct then maybe your amp is a bit "sick".

 

[art_arev]

Any feedback?

 

[boardboy330]

I am using a JVC head with 2v preouts into the bose amp and a sub amp with 12"sub. Its crazy loud and clean. I wont be able to open up the volume half way. I am using Bose speakers. You have changed the speakers to 4 ohm. The amp is 2ohm. But still you must have plenty volume. Changing the speakers from 2ohm to 4 ohm doesnt mean you will lose the volume by half. If your wiring is correct then maybe your amp is a bit "sick".

I had the Bose setup with 1 JL 13W7 then 2 Alpine Type Rs both were pushed by a JL Slash 1000/1. It was stupid loud...but then I swapped the headunit - and the sound got quite a bit lower. Changing speakers - the sound dropped more.

I just finished jumping the speaker lines under the dash and a quick drive around - the speakers are MUCH louder than before. The unit pushes 22w RMS to the speakers that accept 65w RMS. The sound is clean - and much louder than I would ever listen to it.

While I was wiring - I installed the old JL 250/1 amp and when I get the new 12" for the car (E class) - I am pulling the old 10" JL and building a new ported box. I am going sub up, port back.


Sadly, I now have the SRS light on the dash - so I need to rerun the lines and see if I left something disconnected or check the wiring diagrams to see if I should have left a line jumped. I saw quite a few lines that could have been jumped.