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Discussion Starter · #1 · (Edited)
alright this one's a bit complicated to explain.
here's a little recap of my hardware before I layout the problem:
- Kenwood HU with two Amp outputs, one for the fronts and one for the rear that can be switched to subwoofer mode and 4x50w internal amp.
- Kenwood 2channel amp (250 w) for the fronts (has RCA and speakers imputs option) connected to sony comps.
- Signat 5channel amp, 2 channels for front which I'm not using, 2 for the rear connected to kenwood 400w 6x9"s, and one dedicated sub output connected to my pioneer 1000w 12" sub.

since I have only two RCA outs in my HU, my front amp was using the front speakers lead instead of the phono, the front phono lead was going to the back to power the rear speakers.

I thought I'd use the phono to power the front speakers to make them sound a little better with less distortion when the volume's loud and use the speakers lead to power the rears 6x9"s and use them just for midbass.

problem is, my signat amp has only RCA inputs, so I connected the speakers cables out of the HU with RCA female plugs and just plugged the amp's RCA cable into them.
I've turned the gain in my amp to the lowest and gave it a slight LPF filter since the speakers feed is very loud.

It sounds sweet, but now when I put the volume too loud on th HU, it just turns off.
The HU turns off and doesn't come on anymore until I remove its fuse or power cable and put it back, then it turns on just fine like nothing happened.
I didn't test this for very long, just now it didn't cut out, maybe it does only aftre a long period of time running.

is it the amp trying to suck too much power from the HU's internal amp and thus overheating it? any suggestions?

is putting speakers feed into and RCA input on the amp a big no no?
I'm leaving all my cables out for now until I hear some words of wisdom from someone here, so please reply quickly :)
 

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is it the amp trying to suck too much power from the HU's internal amp and thus overheating it? any suggestions?

is putting speakers feed into and RCA input on the amp a big no no?
I'm leaving all my cables out for now until I hear some words of wisdom from someone here, so please reply quickly :)
RCAs are the best to use don't bother will the high level speaker output. There is a very good chance your headunit has a grounding problem.
 

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RCA's tend to carry up to 4V in general.. amps usually allow up to 5 or 9V on the RCA input terminals. Your speaker wires could be carrying 20V or more.. Quite simply, the amp isn't equipped to deal with this high level input. It has gone past the point of clipping and is now saying "wtf are you trying to do to me, man?"

Don't convert speaker to RCA outputs/inputs - it won't work without another amplifer (deamplifier) to reduce the voltage again. You would be much better off (IMHO) using the front RCAs to supply the front amp, and splitting the rear RCAs to become input for the sub and the rears.. the rears will always be at the same relative level to the sub, but you should be able to set this comparative level via the different gain settings on the amp.

[edit] Or if you want to be able to reduce the level of the rears compared to the sub, without changing settings on your amps, you could split the front RCAs to the front amp and the sub input.. that'll mean your fronts and sub always have the same relative output, but your rears can go "up" or "down" in the mix. Come to think of it, that's a much nicer approach.
 

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Discussion Starter · #4 ·
so I'm gonna do the rca split method, thanks.

btw, it's the HU that goes into safe mode, not the amp.
 

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Hrmm.. I can't explain that then, but unless it's a fault with the headunit, I'm sure that splitting the RCA's will work :) Good luck
 

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Discussion Starter · #6 ·
I repositioned my tweeters and it's amazing what difference it makes.
to anyone who has the tweeters on the doors, you should think of putting them in the pillars.
 

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Discussion Starter · #7 · (Edited)
splitting the rear rca into sub and rear speakers is no good, once you plug it to the sub input, it turns the signal into mono for the rear too. I'll split the front with the rear.
 

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splitting the rear rca into sub and rear speakers is no good, once you plug it to the sub input, it turns the signal into mono for the rear too. I'll split the front with the rear.
Are you using Y-leads or putting one RCA plug in to each pair of channels?

Splitting with Y-leads will send a stereo signal to the rear channels and the amp channel, where the sub channel will usually sum them to create its' mono signal internally.

Take rear output RCA's from headunit, and 2 RCA Y-leads.. L and R becomes L, L, R and R. Take one L and one R for the rear channel input and one L and one R for the sub.
 

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Discussion Starter · #9 · (Edited)
I'm done with the install now mark.
I've split the front channels for both pairs of speakers and left the rear channel handle the sub.
I did the Y splitting with the rear channels as you advised and it was the easiest thing to do but when you plug it to the sub input in the amp, it turns the speakers leads to mono too, I know it's weird but that how it is.

I'm glad I finally got around redoing my wiring, resizing the sub box, improving the tweeters position and sound deadening the doors and boot. I can say now that my setup sounds top notch and never disapoints me like it used to on the occasional misreproduced bass note. :)
 
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