Re: Speaker Idea

["Al Powell" <APOWELL@agcom.tamu.edu>]

THOMAST@UWSTOUT.EDU recently said:

> hook the front speakers up normal and hook only the positive terminals up
> to the rear speaker wiring.  sounds like it shouldn't work, i know, but
> _it does_.  this is using all the stock wiring for everything.  sometimes,
> though, i have to turn the stereo off and back on (when i first start the
> car) to get the amp in the rear to work.  

After further thought, I'm not sure whether this is a good idea or 
not.  The rear speaker negative terminals MUST be grounded, or 
supplying a signal to the + side would not work.  The question in my 
mind is whether this specific setup is changing the load (in ohms) to 
the stereo by wiring two speaker curcuits from one powwer source.
If so, long playing, esp. at high volumes, could cause damage to the 
output circuits by overheating as the stereo tries to drive more 
impedence than it is built for.

But this depends on the way the wiring works...and I'm not sure it's 
a problem.  If it has been working for some months, there is evidence 
to say that it's OK.

Actually, if you wanted to , you could build a pseudo-surround system 
in your car by wiring four speakers like this:

>From the positive terminal of the front outputs, you would wire like 
this (flow of power is from left to right, from + to -).

+___ +(spkr 1)- ___ +(spkr 2)- ___ +(spkr 3)- ___ +spkr 4)- ___ -

It's only one circuit and so does not overload the outputs, as long 
as all speakers are impedencce-compatible to the stereo.
This could also be done with the source being the middle two speakers 
in a four-speaker system and feeding the rear deck speakers.  Of course, 
this is more appropriate to a home stereo (It extracts difference info. 
from music and can be used as an imitation-surround).  In a car, the 
rear speakers are generally used more for bass reinforcement....

I think I have totally digressed!!.... :-)

Tom continued: 
 
> i may call crutchfield and see if their adaptor (i heard something about)
> will work, because this setup does add a little noise to the rear speakers
> at low volumes levels.

I have a lot of hiss from my system - but I just installed it last 
might *with* the Crutchfield transformer and haven't had time to mess 
with it.  Heck, my rear speakers aren't working at all.  I'll need to 
solve that problem......

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