Wiring my original AM radio to rear speakers

[gaddied]

I have the original AM radio in my 70 Cuda . And I want to wire two rear speakers to it. But the radio only has one green and one black wire going to the front speaker. The radio works great so I don't want to replace it.
Any way I can splice the speakers to the radio with burning up the radio?  Also what wire is ground the black or the green?

[71vert340]

 A quick question. Are you going to install a fader switch for the speakers? The FSM I have for my 71 Challenger has the wiring for a standard radio w/o stereo with front and rear speakers.

Terry

[anlauto]

Not sure if you would get the power outage you would need to run three speakers off of one feed

[JS29]

If you do, run small magnet style speaker. 

[gaddied]

A quick question. Are you going to install a fader switch for the speakers? The FSM I have for my 71 Challenger has the wiring for a standard radio w/o stereo with front and rear speakers.

Terry

No, I just would like to wire them up with out fader switch.

[gaddied]

If you do, run small magnet style speaker. 

I already have the speakers , they are 4 ohms,75 watts max output, 52 hz-2hz ,89db/ w9 (1M).

[cataclysm80]

Your original radio will run hot and eventually burn up if you run it at less than the 8 ohms it's designed for.
The original speakers were 8 ohm speakers.

Also, the original AM radio was 2 watts. 
You're really not putting out enough power to push 3 speakers, so you should probably install an external amplifier.

I don't recommend what you're attempting to do, but if you really want to try and see what it sounds like, here's how to do it safely...

It sounds like you have an 8 ohm dash speaker, and two 4 ohm rear speakers.

[anlauto]

Excellent diagram 

[cataclysm80]

For comparison, here's a couple ways NOT to do it. 

[cataclysm80]

If you only want to connect the two new speakers, here's your options.

[cataclysm80]

These diagrams are for original radios, which are stable (won't burn up) at 8 ohms.


If anyone out there reading this has a reproduction radio, or an aftermarket radio, they're typically 4 ohm stable.
That's per channel.  Most aftermarket radios have 4 pairs of speaker wires, so they can handle 4 ohms on each pair of speaker wires.

These old original radios have one pair of speaker wires, intended for one dash speaker.


If anyone is looking for replacement 8 ohm speakers to pair with their original radio, check out turnswitch.com

[gaddied]

If you only want to connect the two new speakers, here's your options.

I think I am going to do the two rear speakers only now. So the top wiring diagram with the 8 ohms should be good right?

[Shoooter]

What would happen. If they are all 8 ohms? Would it just cook the radio? No one really uses the radio in these cars anyways

[68bee]

How would you wire it using the 8 ohm dash speaker and a 4 ohm rear speaker

[gaddied]

Thanks for your help!!!!
Wired up the two new speakers today and the AM radio . All works sweet!!