GiZzO

OEM-pac2 is needed along side the wiring harness. It has nothing to do with helping you line up your wiring its for sound intergration so your aftermarket headunit can talk to your bose amp properly.
The bose amp is very unique, its source needs to be low-level (balenced) signal over speaker wire. Most head units produce the normal high-level (unbalenced) signal. Not only are you get double amplification from head unit and again amplifying from amp (you can imagine how this tears up the sound) the signal has to be also corrected to a balenced output. The OEM 2 corrects this taking that unbalenced high level then passing through it, taking it down to low level (balenced) and feeding the bose amp its proper low level balenced. It sits inbetween the head unit and amp.
I know of alot of peope that just hook there HU directly to there bose amp. Sure it sounds OK but it can sound 100x better if you correct the sound output with the OEM-PAC2, its night and day difference. Id highly recommend buying this unit and placing it inbetween your amp and HU (its only $15). The bose system in our cars sounds awesome, just needs extra work to get it hooked up right. Hooking it up <b>without</b> the OEM-PAC2 is going to lead to early distortion and lead to unsatifying results, most like blaming that the bose system sucks and its lack of bass. I had it hooked up without the pac and i was gonna redo everything new amps and speakers....it sucked without it. With the Pac2 success im happy and did not have to change the amp or speakers.

MarcusF

GiZzo is right on the money! The difference is like watching TV on a high def station, versus a regular station. With low-def you can still see the show, but in high def you see so much more. Properly integrating the Bose amp with the head unit makes a very noticeable difference. As inexpensive as the PAC OEM2 is, it should be the first thing purchased.

vickenma

Install was a success! i just posted some quick pics

Tamerz

I am about to do the same thing but am confused as to why I would possibly need this PAC-OEM 2 device. Looking at it shows it can't put out a balanced signal. Balanced signals require 3 conductors per channel. One for ground, one for the signal, and one for the inverted signal. This thing only has two. Just looks like a higher quality line level converter.

Since my head unit has 4v outputs I don't see why they can't just go straight in with proper grounding. Is the noise just from a ground loop of some type?

Edit: Is it something where the signal is on one of the two wires, the inverted signal on the other, and then the system just expecting the exact same ground on both sides for the third?

GiZzO

Im not audio tech so i don't know how to answer the 3 conductor is required for a balanced signal hopefully someone can chime in on that.

But what im sure of is the OEM-2 takes the speaker feed from head unit thats high level to low level. The bose amp wants a low level over speaker wires.
I've tried hooking the HU in 3 configs to Bose amp.
1. No Pac (over amplified, early distortion, constant hiss)
2. RCA HU -PAC- low level bose (low volume, sounded great)
3. high level HU -PAC- low level bose (sounds great, proper volume level)

Using a RCA side is just another option. If its not balancing the signal, hey $12.50 for a line converter is not a bad deal.
Furthermore I just installed a new kenwood headunit in my c280 the unit is 4v. I tried hooking it up RCA from head -PAC- then low level speaker to bose amp. Again volume was too low. So I hooked it up the same way as my CLK (high level to low level speaker for PAC). And had full adjustment of the volume gain on the PAC hooking it up this way.
Its was nice having the flexability going RCA or speaker feed, since RCA low level didn't work even though it was 4v this run.

Tamerz

Well no matter how it works, it sounds like you tried everything and that worked best. Good enough for me. Thanks for the info.

Celts

Hello Guys, Thanks for your informations, very HelpFull...

I am a French Guy, ans just bought a 2002 CLK 320 w208 with Bose AMP.

Here is my ride:


I want to install a Pioneer F700BT in it. I know that the BOSE Amp Does not simplify my installation
If i understand well, i need the PAC2, no problem with that. My problem is to connect all that to the BOSE AMP. I know it is in the rear trunk If i am not wrong ? Did you uses wire from front to rear ? And does anyone has a wiring diagram for connecting it ?

Thanks for your reply.

MarcusF

The PAC OEM2 has input wires and output wires. The head unit wires attach to the wires on the input side of the PAC OEM2. The wires on the output side of the PAC OEM2 attach to a wiring harness adapter. The wiring harness adapter plugs directly into the plug on the vehicle wiring harness. That is the same plug that used to plug into the back of the OEM radio. If you use a wiring harness adapter (Crutchfield gave me mine with the head unit purchase), you won’t have to run wires anywhere or cut any factory wiring.

Celts

Ok, thanks for your quick Answer.
I thought i have to run wire to Rear trunk... Happy not to have to.

I am trying to find a PAC OEM2 (or like) In France, but i can't find it. I have found an equivalent in Germany, (but without Low Level Line IN) especially made for BOSE system (what the vendor said). In fact it acts the same way the PAC OEM2.
If it works, i'll gave the ref.

Thanks for your help.

Celts

Hello All, Thanks to your help, i found The needed item in Germany.
It's that:



It's the same as the PAC2, without the low level entries. Enough for BOSE.

I conneted all in my CLK and it works perfectly.

Thanks you to all of you for help.

Tamerz

I was wondering if you tried going directly from the head unit's RCA outputs to the Bose inputs? I saw you tried the RCA's into the PAC then into the Bose. I misread it at first and thought you tried the RCA's straight to the Bose but it doesn't look like that was mentioned.

GiZzO

Not directly no....
Goes back to your question is the PAC sending out a balenced signal. If not; then yes i've tried it this way cause then the PAC would just be doing line conversion, and i would have done it in the config your suggesting
Its $12.50 who cares it works and gave me options to go speaker level w/ individual gain controls, which i did cause volume was to low over RCA.

spsinha

Celts, can you tell us where you found this and whats its called?

Tamerz

Finally tried this out for fun. Hooked up the 4v outputs from the Alpine I just received directly to the inputs on the Bose. Like you mentioned, the volume doesn't scale well. It gets loud enough but you have to turn the volume way up.

Tamerz

I found this thing by the name of the image:

http://cgi.ebay.de/MERCEDES-Aktivsys...16134003r31186

spsinha

Thanks Tamerz, what area of Chicago do you live in? Attending any of the meets this year?

dennisspeaks

I am looking at rewireing my whole system and leavign the stock in place, however I want to use the steering wheel controls, is there a way to do this?

MarcusF

Leaving the stock "what" in place?

If you're changing head units, it's possible to retain the steering wheel controls, but it depends on the head unit. What brand is the new head unit, and what model?

dennisspeaks

all the stock wires, amp, i am only changing out the sub and speakers, there will be a complete require for the new system with a 400.4 amp, 800.2 amp, MB Quart Rsb 6" speakers with tweets, I just have not decided on the 4" speakers yet. Head unit is a Clarion in dash dvd.

I know I will need to do some custom wiring with the use of an aftermarket harness I assume? That is what I currently have the clarion hooked up to but SQ is not good.

Someone that has done this, instructions appreciated

MarcusF

If the Clarion has an input port for steering wheel controls, a PAC SWI-CAN2 and a PAC SWI-JACK will work. This webpage will tell you how the two boxes go together, how the CAN2 plugs into your factory wiring harness, and how the JACK plugs into your deck.

Gundo

Okay so I ordered a Pac oem 2 on ebay and the seller sent me a pac soem-4 instead. He said this one replaced the oem 2.



Anyways I am a bit confused on how I hook this up. Do I pull out the rca plugs and put in the extra wire set that it came with (pictured), therefore not using rca's at all? Or does it go RCA's from HU to Pac RCA's then Pac wires to VW Harness? Please give me some help on this one, thanks.

Gundo

Also what about the blue black and yellow thicker wires at the top of the unit pictured?

falls profet

Gundo,

The PAC goes right after your HU. In other words, hook up the PAC using the wires on the harness it came with. The RCAs are only needed if you are using an aftermarket amp. ARE you using an aftermarket amp? Sorry if I missed this somewhere...

Gundo

Okay thanks! No just a pioneer HU in coordination with the Bose amp. No other amp involved, I gues I was just confused because the thread talked about using the rca's and stuff.

Gundo

What about the blue black and yellow thicker wires at the top of the unit picture?