I have some new Pioneer speakers rated at 80 watts nominal and 480 watts max and my brother wants to keep the stock AM/FM radio in his 1972 GS. We're going to add 2 more 6-1/2 speakers in the kick panels as soon as we get the molded kick panels so there will be a total of (at least) 4 speakers hooked up to the factory AM/FM radio. My question is, do I need to add an amp with the speakers so that I don't blow something out in the radio?
Without an amp, you won't hurt the radio. In fact, you're more likely to hurt the speakers by turning the volume up too far (along with all the static). An amp will help keep the volume dial at a lower setting, sending less static to the speakers. I say go for it. J ~
Factory radio will not support the new speakers. The old amp wants to see a 10 ohm load. Hook 4 ohm speakers to it and kiss the ouput transistors goodbye. Amp it and you'll take that low quality sound and amp the crap. My guess is it will sound terrible. I'd say leave the factory radio alone, hooked up to the dash speaker, put something in the trunk or glovebox with a wireless remote. All my radios are of the 69 vintage, my guess is your 72 works the same way.
I have a new radio with a remote and we were thinking of hiding it somewhere because my brother wants to keep the "old car" look. If I wanted to hook the factory radio up to new speakers though, what would have to be done to make it work and not fry anything?
Your amp has to see the 10 ohm load, you could hook up the front speaker, then take a high impedance to line level convertor and hook it up in parallel to teh factory speaker and run the line level into the amp. The high to low convertors are around 10K load, so your amp wont even see them. From there hook up the speakers. Im sure there are other ways, but this would be easy. I would choose a cheap amp with built in EQ, since we are not talking high end here.
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=269-050 http://www.parts-express.com/pe/showdetl.cfm?Partnumber=265-124 http://www.parts-express.com/pe/showdetl.cfm?Partnumber=265-085 I have no idea what the Fq response is of the head unit, it's not going to sound great. With the EQ you should be able to drop the gain on the low and high side, so your not Amping noise. As long as your expectations are low, you should be OK:bglasses:
your radio will safely work with 8 ohm speakers. i have four audiovox 8 ohm speakers in my gs - two under the dash & two in the rear deck.
the in-dash am/fm stereo 8 track in my 72 gs, , is from a 78 camaro and thus uses the later wiring cluster. perhaps, what i should have said, is that u can use an 8 ohm speaker to replace a 10 ohm oem speaker. in 1970, i owned a new chevelle and it had an am radio with dual rear speakers and a single in-dash speaker. how gm wired the rear speakers to work, i do not know. i am sure 4 ohm speakers were not available then, where u could wire in series.
Like John asked, if the radio wants to see a 10 ohm load, can I just hook the two 4 ohm speakers in series for a total of 8 ohms?
