THis weekend, I FINALLY added sub and amp to the Factory Bose in my 1996 GLE.

I uses a Scoche LOC-E converter. I ran 8 gauge power and ground, and tapped off of the rear speakers after the Bose amp. My remote was run off of the red 12v+ that goes to the driver's side rear Bose amplifier (worked great) and I tapped the speaker-level signal right off of the terminals on the speakers in the trunk.

Everything powered up great, I set the LP crossover on my old-skool Rockford Fosgate Punch 200ix at 100Hz. Sub is an Infinity Kappa 8" sub in a .33 cubic foot sealed box. The amp is too much for the sub, but this week I am swapping it for my wife's RF 12" sub (her amp is a lot smaller, and so is her trunk).

I am definately getting signal to the amp, and the sub is moving, but the distortion is horrible. I fooled with the settings, but now I have the following problems with setting the gains:

Note- the "bass-boost" control is on the amp, not the LOC, and all tests were done with the stereo volume at normal listening levels (not too loud, but easily perceivable at highway speeds)...

All gains and bass-boost at "0":
Little or no sound from sub.

All gains at "0", bass-boost adjusted:
No difference.

LOC gains at "0", adjust amp gains, bass-boost at "0":
No difference.

LOC gains at "0", adjust amp gains, bass-boost at "max":
No difference.

LOC gain up and played with from 0-25%, amp gains at "0", bass-boost "0":
Sound level increases noticably, but distortion is evident, and increases exponentially as the gain is increased.

LOC gain set around 10%, amp gains played with throughout their range, bass-boost "0":
Sound level increases nominally, but distortion is still evident, and increases as the gain is increased, but not as much as it did with the increases in the LOC gain.

LOC gain set around 10%, amp gains played with throughout their range, bass-boost adjusted:
Sound level increases nominally with teh amp gain, and the inception of bass-boost is at first okay, but QUICKLY adds so much distortion that the sub sounds worse than ever.

LOC stopped at first level where sound is increased, amp gains stopped where distortion is evident, bass boost at about 25% (level where excursion is getting unsettling):
Bass in the car is barely perceivable. Any more gain and I hear distortion. Even turning the volume up to a "loud" setting results in definate distortion. This is really p!$$!ng me off...

So here is where I stand:
I spent 2 hours doing this installation and have no real benefit so far.

Do I try the 12" RF sub and see if it is just the amp overdriving the 8" infinity?
Do I shell out the bucks to get an adapter from sounddomain to have the RCA outs off of the HU?
WTF do I do here? This is driving me nuts!

 

...basically, your problem is that you're sending a signal from the output of the Bose amp to the input of your sub amp, so the input of the sub amp is being heavilly over-driven.

You need to get a signal to your sub amp from a source BEFORE the Bose amp for the rear speaker.

 

You know what? I said that months ago, but was told that it would not work due to the balanced-line nature of the Bose signal. Then I go tto thinking that unless the sounddoamin converter (is it made by PAC) is capable of receiving balanced-line signal and converting it to standard RCA signal, the PRE-amplified Bose signal would have to work. I can see what you mean about distortion, I mean, tapping the audio signal post-amplifier is like heating up dirty water to take a bath.

I would have tried this FIRST, but was told time and time again that I needed to get it at the speaker-level, not at the line-level. I will try this soon.

 

Umm....NO. If you use a line level converter, you do want to tap into the wire feeding the speaker after the amp. If you go before the amp, signal will be too low and you'll have almost nothing going into the amp. Phen, can you get me some pics of this adapter and how you have it wired?

 

The input of your sub amp WANTS a line-level signal.

Before the Bose amp, you HAVE a line-level signal. Why use a converter if you don't need to?

The fewer componenets and level changes in a signal path, the cleaner the sound will be - and there'll be a lot less stuff to troubleshoot as well.

 

While this is basically true, the PRE-amplifier Bose signal is balanced-level, and not a true line-level. I have received mixed reports on whether or not the recipient component has to be equipped to accept the balanced line transmission. Of course, even my statement that it is balanced-level (as opposed to line-level) is heresay, so who knows.

I did the line-level attempt, and it sounds like sh!+.

My LOC is a model LOC-E by Scoche. It has 12+, Gr, and L+,L-,R+, and R- inputs. 12+ and Gr are self-explainatory as to wiring. On the signal-input terminals, I wired the LOC's inputs to the speaker wire terminals on the basket of the Bose speakers in the rear deck, + to + and - to - on right and left, respectively. It was really basic and standard. I think that the problem is that the feedback system in the bose is F'ing me up. Also, I am getting garbage signal, amplifying it, tapping it, converting it to line level, and then amplifying it AGAIN. I will draw up a simple diagram of the wiring tonight and scan it for you in the event that this was not a clear enough explaination.

In reference to your comment about the signal being too low, what seems to be happening now is that any and all gain increases at the LOC result in unbelievable distortion, theoretically because the signal is too STRONG as it stands now.

I wonder if cutting the ends off of an RCA cable and tappign the signal at the PRE amplifier stage (as suggested above) might work...Any thoughts?

 

I only wish you lived close to RI. We could have this fixed in a jiffie!

 

I'm running a jl 250/1. I tapped into the speaker terminals (after the bose amp) and connected it to my amp. I didn't need to use a remote turn on because of the auto signal sensing the amp has. Tapping before the bose amp would not work. I was told that the signal is too low before the amps.

 

What would you suggest? Or, more specifically, what would you do to fix it if I was closer to RI?

If I had more $ I would scrap the whole Bose setup, but for the rears (who really needs rear fill) and the HU it is not too bad. I should get a 4 channel amp and the proper adapter and do a sub and the fronts...

 

It sounds like your trying to do what I've done in mine. Using a line level converter to connect an amp to the bose system. I'd just like to see it to see what is different than mine.