I count three wires per speaker, I suppose the "SE" wires are a shielded ground? I want to make these into RCA cables for a new amp(s) and ditch the factory one. I have a 93 GS with the pioneer system and the dealer was nice enough to give me this diagram. It is different from all the other models as far as I can tell so I wasn't able to find the answer in a search.

What is going on here? I know I left out the 2nd page I can attach that, too in case that helps. If I can splice together some RCAs I think I really have a shot at getting this to work.

So, what do I do with these wires in the context of making some RCA outs? What are the "SE" wires and do I use those with the RCAs I am making or send them somewhere else? I have not installed an amp before.

Thanks everyone. I have answered many, many questions by searching through this forum.

 

...i have an ES and i've thought about removing the stock amp also but if i remove the stock amp, my headunit and CD changer dosen't power up. i don't know if it's gonna be the same case with your car but i think it would be easier to leave the stock amp and use LLCs to attach an external amp. it actually worked great for me.

 

I know yeah that would be easier. I think what you might have done wrong is, in addition to the stock HU's main ground, there is an additional ground with passes through the stock amp, which might have caused them not to power up. Connecting this lead to the stock amp's gound is probably the solution. This HAS been done on an SC but the diagram is different.

Ok, let me ask this, normally when you have 1 wire (or two) per speaker and you want to use them as low-level inputs and make an RCA cable, how do you splice it? There is a middle and outer ring just like on a coax cable. I suppose one is + and one is - . My dilemma is I have this third wire (look at the diagram) and it may be nothing I just want to know before I buy everything I need.

 

Pianoman72:
I can't see enough of your diagrams, and can't tell exactly what you are trying to do. Watch out if you're trying to bypass the stock amp if it receives more than one set of preamp outs from the headunit (make sure you're looking at the right diagram). If you have a CD changer, this may be the case, as in the newer GS's with Pioneer system.

However, I will offer this: You are correct that the SE stuff is the shield for the preamp leads. It also is typically an isolated "signal" ground, which is not necessarily connected to the chassis ground of the headunit, or may only be connected internally at some optimal point for noise minimization. What you can do is connect the main preamp signal wire to the center conductor of the RCA connector, then connect the RCA outer ring to this shield ground. This should provide the proper ground reference for the signal, and also provide grounding for your new RCA shields from the front to rear of the car.

Also need to watch out for the peak-to-peak signal level that you're getting out of the headunit. If you're going into an amp that is equipped with high-level inputs, this should be no problem, but if not, you may need a LLC. (If this is the case you can have the LLC do the RCA conversion for you. Wires (signals/grounds) in, RCA's out. )

 

PS: Make sure you're connecting to the SE (shield ground) that is on the SOURCE end (headunit), as this is where the ground reference IS. The ground must be tied into the headunit.

 

PS one more time:
Since you don't show the other section of diagram, you may have signals that have same name, but with + on one and - on the other. If this is the case, then you can wire the + to the center cond of RCA, and the - to the outer ring. (It is done this way on my '99 GS Nak system)
Just in case.

 

engin_ear, thank you so much for going into that much detail for me. What do you think of my hypothesis that the headunit is actually sending a BALANCED signal? Could that be possible?

https://www.clublexus.com/forums/sho...threadid=81700

I will attach the rest of the diagram but I don't think it provides much help. Don't worry about the CD changer I don't have one anyway.

 

Pianoman72, I can't make out enough detail in your diagram to tell what the wires are for sure.
While it is possible that the signal is balanced, I doubt that it actually is, even if the wires appear to indicate that. Only an oscilloscope will tell. If it is, the signal on the (-) wire will be exactly the negative of the one on the (+) wire for all channels. The reason I say that I doubt that it is balanced: My 99 Nakamichi system has 4 channels of + and - on the schematic, and all of the wires are present in the harnesses - When I checked the signal on each of them with a scope, there was no signal on the (-) wire. What they probably do is use it in a pseudo-balanced configuration where both wires pick up the same noise as they travel through the car, and then this noise is cancelled at the amp's balanced inputs. (Normally, for a balanced input, the (-) signal is subtracted from the (+) signal, yielding a gain of two, while also cancelling common-mode noise. This helps signal to noise ratio. If there is no signal on (-), then no increase in gain.)

I checked your other post: What Percy said. Just use the (+) signal and ground. Not the (-). Your diagram does not reflect what he indicated. You've shown an XLR to RCA connection, in which the RCA is the source, and its ground is wired to the neg of the XLR. You need to ignore the (-) wire and just wire the (+) to center and ground to outer ring of RCA, just one wire to each.

Good luck! Watch your levels, just as important as what wires go where. It would be best to get a test disc (even if you have to play it through a cassette adapter) and check the peak levels on your wires with a scope. That way you know that you will not overload the amp stage. Otherwise, you are playing by ear and a hotly recorded signal may overload and distort.

 

I can't thank you enough. You guys are awesome...I can't wait to start this project now.