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Discussion Starter · #1 ·
Something isn't working quite how I expect... so I'm hoping someone can 'splain it to me! :???:

While preparing to cut the line input wires to the Monsoon amp, I decided to cut just one pair to first measure the output with my MM. (The power is very low by the way... so I do believe that I can just solder some RCA plugs to the correct wires and then just plug then into the RCA inputs on the amp.)

Since I am going to keep the Monsoon amp for the rears for the time being, I set the fader to the front. Then snipped one pair.

There are green (right rear), red (right front), yellow (left front) and blue (left rear). Wrapped around each colored wire is a brown wire, which is the corresponding ground wire for each color.

So when I snipped the yellow pair, I assumed that the left front speakers would go dead.

Wrong. Both left and right speakers went out. :crazy: I did nothing to the red pair, which is supposed to be for the right.

Is it possible that both the right and left front speakers are sharing the same ground? If I put the yellow wire back together without reconnecting the brown, I get sound... from both sides. If I put the brown back together, I get sound... from both sides.

I looked at the connector going into the head unit. The brown wire wrapped around each colored one is the wire directly opposite it and is supposedly the "minus" according to the diagram on the headunit.

I'm afraid to start sorting out the wires that go from the amp to the speakers.
 

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Discussion Starter · #3 ·
But I want to continue using the Monsoon amp for the rear. Doesn't that Blau adapter plug right into the head unit?

I really want to avoid until I am ready to add a separate amp for the rear speakers.
 

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Then either leave the Monsoon alone until you do all 4 or don't do it at all. There will be a HORRIBLE gain mismatch if you use the Monsoon in the rear and an aftermarket in the front and the rears will be WAAAAAAY too loud.


Paul :thumbup:
 

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Discussion Starter · #5 ·
If my aftermarket amp (an Infinity) as 111w/channel and the Monsoon feeds like 30 to the rears, why will it be way too loud? Why? I'm not questioning your expertise here or your judgement, but I'm confused.

I proposed this idea (using aftermarket to drive my front comps with mono sub out) and the Monsoon for the rear a while back... in this very thread:
http://www.clubb5.com/forums/viewtopic.php?t=87116&highlight=

You didn't mention that back then.

Besides... can't I just used the fader knob on the HU in addition to the input gain on the Infinity amp to balance it?
 

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I did, I voted for plan A. And it's not really about power, it's about gain. If the gain on the rear is a lot higher then it'll get to it's max power output faster than the fronts. So up until the point where the fronts are finally getting more power than the rears then the rears will be louder. Just because an amp makes 111 wattsdoesn't mean it makes that much all the time. In fact, component sets will usually only require about 10 watts to get to very high levels. You can use the gain on the Infinity to balance it but it'll do 2 things, create a lot of unnecessary system noise and the amp will go into clipping very early.


Paul :thumbup:
 

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Discussion Starter · #7 ·
Okay. I guess I misunderstood in the earlier thread and what you say about gain and clipping do make sense.

Then I will go ahead and add the second amp now too.

How much power do I need in that second amp so that it won't be too loud or too quiet?

I suppose I could just get a 4 channel amp and use the Infinity to drive the sub by itself... http://www.crutchfield.com/S-d4kF1A...g=120&I=108R7540A&o=p&a=0&cc=01&avf=N&search=

though I think it might be too much for the 10 inch JL (2 ohm)
 

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What you can do is either use the amp you have now for the door speakers and a new amp for the sub or use the current amp for the fronts and subs add get a smaller (say 50x2) for the rears. Again with the rears it's not so much about the power but having the ability to adjust the gain, which you can't do with the Monsoon amp.

What model JL sub is it? I can recommend an amp based on which model it is.


Paul :thumbup:
 

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Don't add the eq yet. Make the system sound as good as you can without the eq and then add it. That way you won't be tempted to use the eq to try to solve problems better solved by other means.


Paul :thumbup:
 

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Discussion Starter · #13 ·
I'm almost afraid to ask what those "other means" are?? :lol:

The Infinity amp has a 12 db boost at 50 hz for the sub and I think the high pass is also variable. So I guess I have a lot to play with. Thanks.
 

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can I make a humble suggestion. Dont use the rear speakers. The tweeter in the rear door will cause you all kinds of grief, plus the speakers in the rear doors are "subwoofers" and may not blend well with your sub.

After some experimentation I ended up leaving the rear speakers out of may system with excelent results.

By the way....the output from the deck is at speaker level...use an LOC, It will give you far more flexibility when setting your gains in your system.

I seem to remember something similar hapening when I snipped the wires too...I dont recall how I resolved it so it must not have been a big deal.
 

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hhmmm....I went out and looked at my wiring. red and yellow with thier corrosponding brown grounds. The other wires are capped off. I think that I noticed the same thing as you but once I cut all the wires I had no more problems.
 

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Discussion Starter · #20 ·
I measured the output from one of my channels being fed into the Monsoon amp. It was something on the order of 1 to 2 volts AC.

This is supposedly the correct Blaupunkt adapter to use with the Monsoon HU: http://www.midwestelectronics.com/product_info.php/products_id/140

It is nothing but a plug for the HU with four female RCA's attached. It can't be a line out converter.

I have read about an equal number of opinions that say the output is speaker level versus line level. My Bentley manual clearly says that if equiped with a Monsoon amp... the output from the HU is line level.

Is it possible that it is both?? Doesn't VW code the HU depending on the configuration? Gives it speaker level output without the Monsoon and line level with the Monsoon.

At any rate... my amp has a speaker level input and will try that first before I solder RCA's onto the wires. If it seems the volume is too low.. then I'll attach the RCA's.

As far as the rear speakers go... I like having rear sound and already have installed a new set of comps and have a new amp (Alpine) ready to go in. I like to have the rears adjusted so that I can just barely hear them. And since I don't have my sub yet... I think it will sound a bit thin without them. Until the sub is installed.. I intend to use the rear amp bass boost a bit.

Thanks for looking at your wiring.
 
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