1978 firebird am/fm/cb radio

[DirtyWhite77]

Hi guys I recently bought a gm radio cb combo unit at a swap meet. Got it home and through google I’ve found out it’s the same radio you could get in 78-84? in Cadillac Pontiac Oldsmobile cars. The top 3/4 an inch of the radio is the cb and controls. The bottom section of the radio is your normal am/fm radio. It says Delco on the face, it says gm all one the back. It looks exactly like this
https://www.firebirdcentral.com/1978_1981_Firebird_AM_FM_Stereo_Radio_with_CB_p/das-2550e.htm
Mine needs refurbished definitely and I don’t have the mic or the splitter. I do have the factory knobs though. I have a radio repair guy I’ll send it to for an overhaul.


Does anyone know what size and ohm rating of speakers I should use with this unit? Are these 2 channel only or can you run the package tray speakers AND the dash speaker?

[roadking77]

Congrats on finding a great radio! One thing I look for at swap meets is a good original radio. Most of the time they were changed when brand new so by logic one would think there are a lot of decent ones out there.

I would assume that this radio would be 10 ohm. I think most modern units are different maybe 8? Not sure on the channels, but you should be able to run the dash and the package shelf separately. It probably has a fade (front and rear) but no balance (left and right).

[Wallington]

Stock was 10ohm, more recently use 4ohm. Volvo and some others used 8ohm in the 70's. Stock original speakers can still be had, as well as newer alternatives if keeping original, sound quality will likely only be so good. Otherwise amps and similar can be used in order for standard new speakers, depending on how much you want to alter the car.

[roadking77]

Thanks, I was fairly certain on the 10ohm part but a bit unsure of what is commonly used now. As you can tell I dont use car radios that much 

[5th T/A]

Hi guys I recently bought a gm radio cb combo unit at a swap meet. Got it home and through google I’ve found out it’s the same radio you could get in 78-84? in Cadillac Pontiac Oldsmobile cars. The top 3/4 an inch of the radio is the cb and controls. The bottom section of the radio is your normal am/fm radio. It says Delco on the face, it says gm all one the back. It looks exactly like this
https://www.firebirdcentral.com/1978_1981_Firebird_AM_FM_Stereo_Radio_with_CB_p/das-2550e.htm
Mine needs refurbished definitely and I don’t have the mic or the splitter. I do have the factory knobs though. I have a radio repair guy I’ll send it to for an overhaul.


Does anyone know what size and ohm rating of speakers I should use with this unit? Are these 2 channel only or can you run the package tray speakers AND the dash speaker?

As mentioned most GM radios of that era used 10 ohm speakers. You could probably get away with running 8 ohm speakers but 4 ohm speakers may damage the radio.

[roadking77]

At one time Ames sold the 10 ohm speakers but I havent checked on them in awhile.

[Wallington]

Also, the radio shown was option UP-5, new in 1978 and also a Firebird option.
There was also a stereo version with Stereo Indicator light called UP-6. Not a Firebird option until possibly 80-81 with dash corner speaker option.

[TTAPaceCar]

Hi guys I recently bought a gm radio cb combo unit at a swap meet. Got it home and through google I’ve found out it’s the same radio you could get in 78-84? in Cadillac Pontiac Oldsmobile cars. The top 3/4 an inch of the radio is the cb and controls. The bottom section of the radio is your normal am/fm radio. It says Delco on the face, it says gm all one the back. It looks exactly like this
https://www.firebirdcentral.com/1978_1981_Firebird_AM_FM_Stereo_Radio_with_CB_p/das-2550e.htm
Mine needs refurbished definitely and I don’t have the mic or the splitter. I do have the factory knobs though. I have a radio repair guy I’ll send it to for an overhaul.


Does anyone know what size and ohm rating of speakers I should use with this unit? Are these 2 channel only or can you run the package tray speakers AND the dash speaker?

Your repair guy should know if he's knowledgeable enough to overhaul it.
The radios from the ERA are all 2 channel. They use potentiometers to split each channel to four (front, rear)
I believe 4 OHM speakers will be fine. However both wires must be isolated from (Chassis) ground. A modern power amp (with isolated speaker level input) can also be used that can power a wide range of modern speakers!  Including a sub-woofer etc....
   

[DirtyWhite77]

Thanks guys! My radio guy can sort me out, but he’s very old and on the other side of the country. I didn’t want to call him and try to explain what I had, or pay the $25 to ship it to him for him to tell it’s not what I want. And I wanted to get an idea of what this can do before I invest a bunch of time and money in it.



MY radio does have the stereo light to the passenger side of the am/fm switch. So that means my radio is a 80+ model? Thank you for that I will google that code and find out more about it. These old radios are so different. Between my ford truk radios and this and the various ways of wiring. Even a aradio made in 76 can work completely differently than a 80+ as far as speakers that will work or how they want them wired.
Would a 1980+ radio work in my 1977’s factory location?

How would I go about connecting this radio to an amp? I’m really ignorant of sound and audio.

[b_hill_86]

Two ways (in general). One being you utilize an amp that accepts speaker level inputs meaning the same wires that would connect to a speaker instead go to the amp which recognizes they’re “higher power” than the alternative I’ll explain in a sec. I believe there can be some disadvantages to this way but don’t quote me on that.

The other way, utilize a line-output converter. It easily connects to the speaker outputs on the radio and reduces the output to line level (think rca style cables with red and white plugs) then you use said cables to connect to the line input on the amp. That’s how I have my 77 (which has slightly different output than 78+) hooked to a modern Bluetooth enabled amp. I have a thread on here with the line output converter pictured or you can google it.

Radio shops could also add line outputs prior to the radios internal amp but that would require modifying the radio.

Also your radio will not fit in a 77 fyi. 70-77 has a smaller radio opening than 79-81.

[Wallington]

No, it's still a 1978+ model radio, other vehicles had the stereo option, Firebird didn't.
As Brian said, if you have an original 77 dash, a 78 radio won't fit.

[firebirdparts]

I don't know about the ohms, but i do know those are all 4 speaker stereos with a fader.  I actually had one.  I had a 1979 Olds Toronado Diesel and those were actually common.  They used a power antenna (standard equipment) with a big field coil on it.  They were common in Eldorados.  78 Firebird used a CB antenna hidden under the dash.  Probably not great.

Trying to figure out how we could find the ohms.  I will look in the parts books..... There's no comment in the parts books, but they do show the same part number for 77 and 78.  I will look in my 78's with original radios and see what they have (no CB's)

[Wallington]

Stamped on the radio housing, speakers and common knowledge.