<VV> Installing radio in Corvair

[tony.underwood at cox.net]

---- Clark Hartzel <chartzel at comcast.net> wrote: 
> OK you electronic wizards, I have a question.  I bought a new radio to
> put in my 1965 Monza sedan.  It is a Panasonic digital 4 speaker stereo
> but I am only using two speakers (both in the front).  Do I just leave
> two speaker wire sets unattached or do I combine the left front and the
> right front into one speaker and the left rear and right rear into the
> other speaker?  

Most modern aftermarket car radios of any substance will be using high power (relatively speaking) audio output devices, many of them CMOS based.  Such devices will have a DC component on each speaker wire which can damage the output device (usually an IC or hybrid module) or cause unstable operation if you connect them together... and/or cause terminal (pun intended) damage to the device if the speaker wires are grounded, which can allow the magic smoke to escape.    Thus:  

Do NOT connect any speaker wires to anything else other than a speaker and then make sure it's only ONE speaker to ONE pair of speaker wires.   Don't connect them together.  Don't ground them.   Don't allow them to touch anything else metallic.   Tape them up and tie them off unless they're actually connected to a speaker.  

> I am thinking if I leave two of the four speaker wire sets unattached I
> will lose half the music 

Actually no.    The rear channel speaker outputs are simply clone copies of the front channel outputs in most cases.    In a few obscure instances you will see bi-amp systems with the rear speaker outputs having high freqs rolled off and producing mostly base and lower midrange sounds, while the front outputs will have low freqs clipped out and producing mid and high frequency sounds, thus working the "woofer and tweeter" thing.   These bi-amp radios are mostly long gone these eays, not seen much anymore, so it's unlikely you'll have any issues by simply using the front outputs running to a pair of speakers and taping up the other speaker wires and tying them up and out of the way.    

> but then if I combine two sets of wires to one
> speaker I might damage the radio.  

More than likely, yes if the radio is using those modern output devices.  

Run the front speaker output wires to a pair of full range speakers and all should be well.  You can also get into the radio's menu (if it has "pushbutton" electronic volume and tone controls) and simply turn off the rear speaker outputs with the fader controls, which will keep the rear output devices from working hard trying to deliver audio to a speaker that's not there.   

...hope this helps. 

tony..