Stock early 80's GM AC Delco AM/FM.
I don't know much about audio or car audio for that matter but I guess now is the time to learn. I'm restoring a 1978 GMC truck and I was given a AM/FM out of a 1982 truck for free.
Originally these trucks had 1 speaker and it was an awkwardly sized 4.5x11 speaker in the dash. I am not sure of the ohm rating of headunit or speaker. EDIT: Part #16009960 for the headunit. 10 ohm speakers and no speaker ground.
I plan on putting two tweeters up front where the 4.5x11 should go and then I've bought some brackets that add two 6x9 speakers in the cab corners behind the seat.
I need help finding a speaker that will work well with this older unit.. I don't want to kill the unit with the incorrect ohm rating or whatever else.
Also, amplifier? Just wondering if it might be better to hook up the unit to an amp and have the amp control the speakers instead.
Posted Feb 27, 2017, 3:53 AM UTC · edited
You're much better off making a plate for the 4x10 hole and running a pair of 3.5" or 4" speakers (whatever fits). Decent 3.5's are about the same price as decent tweeters anyway.
You get full range stereo sound, which is far better than only having tweeters in front of you and 6x9's firing into your ass.
As for impedance, just run 4ohms all around, as is standard. There's thousands of options on the market.
As for an amp, since you're using a factory radio, you'll be better served by spending the money on an aftermarket radio. You'll get a nice boost in power, the speakers will be happy, and you'll gain all the features and adjustments that 35 year old factory radio is missing, like bluetooth and ipod.
The problem is the old radio outputs 8-10 ohm and I'm not sure how to make it all work. I'm not really in the market for a stereo, which is why I'm glad I got the radio for free.
I've been looking for more information occasionally at work but I've not found much. I'm guessing I need to find a way to lower the impedance down with some sort of converter or adapter and wire that to a basic amp under the seat bracket I have to fabricate up still.. and speakers out from the amp.
I'm not too picky, I just want something that's not terrible and that's not going to fry itself under the dash.
Just throw in the radio and speakers.
You're wayyyyy overthinking things.
I don't think I'm all that out of line when the part number (16009960) information says 10 ohm speakers only. No grounded speaker connections.
I just don't want to burn out the head unit is all.
EDIT: I see now that I could wire the two 4ohm speakers in the cab corners in a series to total up to 8 ohms. How would that affect the sound?
Restoparts makes 10ohm replacements.
It would sound like shit at any volume.
Stock audio equipment today doesn't all sounds d that good and you're trying to do way too much with very old, very cheaply made equipment.
Does the 82 radio have left and right outputs or single speaker like your original radio? I'd imagine both being it's a FM unit.
Just run the stock deck to a LOC and run an amp from that signal and hope for the best. You're not going to get any good results trying to run multiple speakers off that old radio.