Adding Rear Speakers to 1969 Convertible
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Adding Rear Speakers to 1969 Convertible
Greetings, Friends. I searched the threads but didn't find an answer.
I've got the original 1969 radio in my car. I'm going to replace the kickplate 4x10 speakers with same size new replacements. For better sound, I want to add rear speakers as I have read that some of you have done. I know that the radio needs to run 8 ohm speakers. My question is this: Do I wire the rear speakers in series or parallel with the respective RH and LH front kickplate speakers? If I run them in series, I think that I should use 4 ohm speakers both up front and in the rear since the added resistance in series would be the 8 ohms that the radio sees. If I wire either 4 ohm or 8 ohm speakers in parallel, the total resistance of the circuit is 1/(Rt)=1/(r1)+1/(r2). Remember back to high school shop class. Meaning that the resistance would be either 4 ohms for a parallel 8 ohm speaker pair or 2 ohms for a parallel 4 ohm speaker pair. I've got to figure this out in order to purchase the right speakers all around. Any advice from you that have done this would be very much appreciated. Thanks!
I've got the original 1969 radio in my car. I'm going to replace the kickplate 4x10 speakers with same size new replacements. For better sound, I want to add rear speakers as I have read that some of you have done. I know that the radio needs to run 8 ohm speakers. My question is this: Do I wire the rear speakers in series or parallel with the respective RH and LH front kickplate speakers? If I run them in series, I think that I should use 4 ohm speakers both up front and in the rear since the added resistance in series would be the 8 ohms that the radio sees. If I wire either 4 ohm or 8 ohm speakers in parallel, the total resistance of the circuit is 1/(Rt)=1/(r1)+1/(r2). Remember back to high school shop class. Meaning that the resistance would be either 4 ohms for a parallel 8 ohm speaker pair or 2 ohms for a parallel 4 ohm speaker pair. I've got to figure this out in order to purchase the right speakers all around. Any advice from you that have done this would be very much appreciated. Thanks!
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Joined: Jan 2006
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If your amp has output connections for front-R, front-L, rear-R, and rear-L, then all you need to do is select speakers to match the rated output impedence and plug them in (or you can select speakers with higher impedence at the expense of max. output/volume). If you have just a stereo radio/amp head, then you need to make each side have the correct matching impedence for R and L outputs on the amp. Your resistance calculations are correct: put speakers (of same ohms) in parallel and you cut the total speaker impedence in half; put them in series, you double the total impedence.
