RADIO Wiring

I have an original buick radio wired up to 1 front speaker and 2 back speaker, I want to upgrade my radio system but keep the original one in place and hide a new one somewhere (glovebox...etc...).If I want my original one to still work (if I feel like listening to old radio) Can I connect power to both radio and splice the 3 speakers (Y) to both radio, will it works if I turn just 1 radio on at the time????? Thanks

 

I think you will best best off using diodes in the wires to eliminate any feed back to each unit and possible damage . I sure someone else with more knowledge will chime in . Also there is a difference in the ohms rating for the old radios and the new ones . Can't remember the numbers but I think if you use the speakers designed for the later radios it will hurt the older ones .

 

Hey Mike,
Pardon my lack of knowledge but what are diode and what do they do?As for speakers, you mean the new speaker will hurt the old radio?.....

I notice my front speaker is the original one (looks like that anyway), maybe I should plug the new radio only in the back speaker and the old one in the front speaker...?

 

OK on the speakers some are 4 ohm and some are 8 ohm . I will have to get in my files to make sure which you need for the old radio . A diode is like a one way valve for electrical current . It will let to current go in one direction but not flow back the other way . Radio Shack has them. Simplest solution for you is run original radio on front speaker and new radio on rear speakers . There is a good article to how to convert the single front speaker to a dual at the same place in the dash as original .

 

Thanks Mike, Thats what I will do, I will leave the front speaker mono, I wont use it much anyway, its just to say that it works! Thank you, I now know what a diode do!

 

I wouldn't use a diode, it can chop the signal. Relays would be the way to go if you ever decide you want to use all of your speakers.

If you are an audiophile, may want to get something solid state that has been benched for the audible frequency ranges. If on a budget, you could go for the old school mechanical relay board like this one:

http://cgi.ebay.com/4-RELAY-BOARD-r...5|66:2|65:12|39:1|240:1318|301:0|293:1|294:50

Or even just get some 12 volt relays for few cents and build the bread board yourself.

Wire all of the relays to activate in series with the radio switch, and it will automatically switch your speakers when you turn on the radio.
Easy cheese!

Peace;
yergi

 

If you need to wire two rear 4 ohm speakers to 8 ohms the following may help. If you use them both in 4 ohm, it can overload the transister amplifier and short your sound out. This worked for me:

On the drivers side of the radio, in order, you have yellow(+12V), Green (front speaker+), Black (front speaker grnd -), and on the passenger side of the radio, a single blue lead for the rear speaker. The - side of the rear speaker is grounded. The original speakers were 10 ohm, replacement car speakers these days are 4 ohm. You can wire 2 4 ohm speakers in series and get 8 ohms. In case you don't know how to do that, you connect the wire from the radio to the + side of spkr1, then - side of spkr1 to + side of spkr2, then ground - side of spkr2. Hope that helps

Wire them in series, like I described. The ohms symbol looks like a horseshoe. Look on the speaker, the label on the magnet, it will say 4 ohm. Wire the 2 speakers in series and you get 8 ohms. The original speaker was a 10 ohm unit. It's close enough.

Here's where it gets a little weird, if you hook 2 speakers up in parallel you get 1/2 the impedance, if you hook them in series you get twice the impedance. Parallel is taking the two positive wires from 2 speakers and connected them with the positive from the radio and doing the same with their negative wires. That's parallel, 2 4 ohm speakers give you 2 ohms impedance, not what you want. If you hook the positive from your radio to the positive of speaker A, then connect the negative of speaker A to the positive of speaker B, then connect the negative of Speaker B to your radio (or ground) that is Series. Like a daisy chain. Hooking 2 4 ohm speakers in Series will give you 8 ohms resistance and you should get nice clear sound. Try it as an experiment and see what happens. If it works both speakers will be playing 1 side of the stereo. You'll need 2 more speakers to play the other channel. Instead of speakers I think you can add a 4 or 6 ohm resistor (in series) to create the expected load.

Series Wiring of Two Identical Speakers
The figure below shows the wiring for two identical speakers in series:

Figure 1. Series Wiring of Two Speakers.
This wiring is often used with two 4 ohm speakers (bringing the total system impedance to 8 ohms).
Series Wiring of Two Identical Speakers
For 8 ohm speakers For 4 ohm speakers
System Impedance 16 Ohms 8 Ohms
System Power Capacity Twice any one speaker Twice any one speaker
One thing to keep in mind with this wiring configuration: if one speaker blows (resulting in an open circuit), the second speaker will go silent (like the old fashioned Christmas lights, "if one goes out they all go out").

 

Whoa... this is getting technical, and english is my 2nd language here!I ll try the simpliest thing first (old am/fn in single front speaker and new cd/mp3 player in the 2 back 80's speakers....we'll see what that does. But thanks anyway for the response!