C2 radio speakers?

[Patrick B.]

I had to remove my 67 radio to get my heater core out, and it had a kluge of a speaker installation. The attached pic shows a transformer that was screwed onto the back of the radio (interfering with heater box removal) wired in parallel with the speaker along with some kind of capacitor in series with the speaker. Oddly enough, the radio still worked OK even though the body has been off the frame for 20 years, and the speaker was rigged like this.

IMG_1182.jpg

I assume this was because the speaker was not like an OE speaker. The Paragon catalog mentions 4 ohm, 8 ohm and 10 ohm speakers. What value speaker was OE equipment that could be connected directly to the radio without this mess? Did an OE speaker have a transformer like the one stuck to back of my radio actually built in? If so what was its function? I simply want to replaced the buggered up speaker wires and use a speaker that is a direct replacement of OE if that exists.

[Joe R.]

Re: C2 radio speakers?

Patrick,

A 10 ohm speaker was OE and there have been rumors that anything but a 10 ohm speaker will burn your Corvette to the ground. THOSE RUMORS ARE UNTRUE! Radios and speakers are matched by impedience and not ohms however ohms is a part of the formula used in the match.
An excellent speaker is sold by Volunteer Corvettes in Knoxville, TN. Original speakers such as the ones sold by Volunteer has the transformer ON the speaker just like the original.
You will have to remove that transformer from your radio. Some Jake-leg attached that one from an original speaker.

JR

[Donald H.]

Re: C2 radio speakers?

Pat,

I was looking for one a while back, but never bought. There were some good references in this forum for S&M Electron Tech (link below). A little over half way down the Classic Car Speakers page is a listing for their 58-67 speaker.

http://www.turnswitch.com/speakers.htm

Don

[Joe R.]

Re: C2 radio speakers?

Hi Joe,

You have it pretty much right. Amplifiers need to be compatible with the impedance they are driving. Impedance is AC resistance. It is measured in Ohms, same as DC resistance. The transformer is used to match the output impedance of the amplifier (so the amplifier "sees" the same impedance as its output impedance). That maximizes power transfer.

Joe

[Patrick B.]

Re: C2 radio speakers?

Joe: I take it the DA27 speaker from Volunteer (8 ohm with transformer) is the one you have had success with. Thanks fellows for the information.

[Joe R.]

Re: C2 radio speakers?

Patrick,

Yep, Have purchased probably a hundred on them and never a problem.

JR