Hi I have a 84 T/A 15th anniv. with the performance sound option and I have a quick question for you guru's out there. Can the factory amp work with a aftermarket radio? The original radio in this car is long gone and I am at the stage of my interior resto where I am thinking about a sound system. I am trying to keep the car as original as possible so I want to keep the amp it if it will work but if it wont then its probably not worth keeping it in the car.
Any thoughts?

 

negative, if its a bose theyre proprietary, meaning an aftermarket deck wouldnt communicate with the factory amp, i spend most of my time at work bypassing factory amps, every once in a while you can integrate but bose is a no go in most cases

 

Hmm you are probably right. I wonder how the thing actually works? It is just a switch on the dash.

 

Im not sure to be honest, my bose system didnt have a sub, id just bypass it and come to cartoys

 

Lol Thanks for the help bro

 

The firebird system is not a Bose system, and a Bose system is extremely fickle like you described. This system I would imagine would imagine work only because it uses audio in's, and just like you would turn down an aftermarket amp, I think this amp is pre-tuned to turn the gain down, cause I'm pretty sure the radio is like Monsoon, just a regular deck. Anyways, I believe I've read that the '85 system was a calabo with pioneer or blaukpunk or something like that, and the radio ran the 4 4x6's like normal, and the amp powered the two subwoofers in the special boxs. I know the wiring is the same for the '84, but not sure on any manufacturers names. I have like 3 sets of custom sub boxes for the performance sound, and only one set still had the factory subs still in the box, the subs were known to blow even with the tiny amp. Anyways, all the 4x6's in the car were Delco, and i'm not sure of the sub. It's not like the audio systems nowadays that when it says pioneer system it's pioneer speakers and all.

 

4x6s???? all around? i thought there were 6x9s in the sail panels

ive never really gotten in depth on factory audio options for our cars i know there were some with subs in the sail panels etc etc

from the installer side, i say rip it all out and lets make it loud, from a personal standpoint if you could get it to work that would be kinda cool

 

The performance sound option kept the 4X6s in the dash, but in the back, there was a csutom box made that held a 4x6 at the top of each box that had an open back (instead of a box), and then below, a nice size box that fit into the hollow part of the sail panel area housed a 5" subwoofer even though many of the things i've read said 4", if i remember correctly it was like 5.25", anyways, those subs were powered by the amplifier by the passengers left knee. The switch on the dash turned the amplifier on, thus why i say that the stereo is regular because you could turn the subwoofers off, anyways, the gain switch turned it up or down strength wise.

 

Eh... its probably not worth it I ordered some 6x9s so I am just going to ditch the factory system. Ordered some cheap 12" subs and an amp too so I think my audio needs will be met. Thanks for the help guys.

 

In case you are still looking for a replacement 5" woofer, the Dayton Audio RS125-8 may be a good option. I measured the resistance of my factory sub (7.7Ω) and the Dayton speaker states that it measures 5.86Ω. This may be a close enough match to let the factory amp work with this speaker. I don't see why an aftermarket radio would not work with the factory sub amp since the sub amp grabs the signal from each of the 4 speaker signals. You may have to keep the volume low since (and this is just a guess) the gain of the factory amp is set to match the output of the factory head unit. An aftermarket head unit will be capable of sending a higher signal to the amplifier causing it to clip.

Since I am using an aftermarket amp, I bought the 4Ω version of these speakers (RS125-4), but I have not installed them yet. I plan to add a 2 way crossover and have the 5" woofer play from 125 Hz to 500Hz and then a 4"x6" play anything higher than 500Hz.

The factory setup (as seen in my '84 Firebird service manual) has two 10Ω 5" woofers connected in parallel to the amplifier in the dash. The amplifier has a low-pass cutoff of 500 Hz. The factory woofer frame is 5" at the widest parts near the mounting holes and about 4.625" between the mounting holes. It has a cutout diameter of 4". The cone is 3.25" with 0.5" of foam all around. It has a mounting depth of about 2.25". I have no way of measuring the T/S parameters which are needed to find an optimum replacement.

 

I do not know if anyone has imformation on where the Sub Woofer Amp. would be on a 1984 Trans Am ???
I have noticed that when I turn my factory radio on the switch for the amp lite up, and I cannot turn the Amp off other than turning the radio off is this normal ???
If it is the switch does anyone know where I can get another one ???

 

I recommend starting a new thread for this.