I got a PAC OEM-2 4ch LOC and it has both Low and High input lines. in their manual they describe the scenario where I would use the low input lines to tap into the speaker lines coming out of the head unit and so I did. put a CD with a constant 1khz signal coming out and getting no voltage on the RCA's from the LOC.

What am I dealing with here? Bad LOC? or maybe not enough voltage on the HU lines that the LOC cannot function?

 

You need to tap the speaker line after the stock amp. Either at the amp connector, or at the speakers.

 

but then I wouldn't be getting a good clean signal. it would be already processed signal from the amp. With this LOC I have, it alows to adjust the RCA pre-outs from 2v to 9v as long as you have around 1v signal coming in to it. I dunno gonna have to do more testing...

 

That's how mine is setup & it works fine. I have the low level spliced into the rear speaker outs from the stock amp.

You can also just splice in a pair of RCA's to the signal cable from the HU to the amp. This is already a high level signal. I did that on my old CLS.

 

There are two schools of thought:

1) The more gain, the better, so grab it after the amplifier (called the"Navone" school).

This ignores the distortions added by going through the amplifier, along with any equalization, crossover filtering, or compression which occurs.

2) The cleaner signal is available before the amplifier, so use it and find a way to work with the voltage level and signal type available.

The HU has full-range balanced differential signal outputs to the Bose amp.

We've used them several times with great results - BUT best results are obtained with amps with "balanced"-compatible inputs. Common-grounded inputs no workee so well.

What amps are you using?

Often, the best sounding "LOC" in this case is a good sounding ground loop isolator (think Soundgate Iso2Lite).

 

It's not a high level signal. It's a low-level balanced signal.

 

I am not familiar with that LOC... but you might need to rotate the pots counter-clockwise rather than clockwise.

Many LOCs seem to have this problem

 

I tried to turn them back and forth with no results. I'll go see now what the signal from HU is and then I'll know for sure if it's a bad LOC.

 

And so I tested some more.... I unplugged the amp connector tapped into one of the low input lines again and at max potentiometer setting was getting only 1.8v at full volume on the LOC RCA output. Once I plug it back into the amp the the RCA shows 0.002v (pretty much dead). Then I tapped into the High output line that goes from amp to speaker and I am getting maybe 0.3v on the LOC RCA out at full pot. setting.

Conclusion: I think the LOC is bad.

Wasted so much time....

 

went to a small electronics shop and they had some RadioShack LOCs from 1997. DAMN those things are old!! hooked everything up and....... my Type R is pounding pretty hard Didn't finish tuning it but I am powering it off of my speaker amp until my monoblock sub amp comes in so no need to be very particular about that. I am now faced with 2 other problems... 1. where to mount amps and 2. lights are dimming every time the sub hits so it's drawing power pretty good. I wonder if it's going to be better with class D amp as it's supposed to be more efficient.