This info was copied starting at pg. 86-6-11

 

Ahh thanks again!

 

Enclosed Bose speakers just in case mud gets flung into the vehicle

 

what did you do to install a new amp for it because I didn’t think it came with one stock. Correct me if I’m wrong but isn’t the amp apart of the radio in the car

 

No. The amp is under the driver's seat.

 

Somewhere I learned there is two types of radios.
The 'high end' type is the one that outputs not-speaker-levels ('line levels') ---> towards a necessary separate power amplifier under the driver's seat. Seen the guts of that radio has provisions for implementing an audio amplifier integrated circuit in the back of its mainboard, that way becomes the 'low end head' that would feed speakers directly with no amplifier under seat.
The amplifier is not a part of the radio on the 'high end type' The amplifier is apart from the 'high end type'

The best replacement speakers are healthy originals obtained at a boneyard. They are matched-equalized to the vehicle room acoustics. Factory did not install anything random as in a seventies car.

 

Interesting. All three of mine have had amps even though only one was the "high line" system.

 

The schematics for the base/mid line show speakers connected directly to the head unit. Only the high line has the power amp under the driver's seat. It's possible that the base / mid line audio configuration with the external power amplifier was a production optimization. Both can share the same wiring harness.

 

Replacement speakers should not sound worse if they match the parameters like impedance, frequency range, SPL (sound pressure level) aso. of the original speakers. Original speakers (given they are still in good condition) can be measured to find the best replacement, but that's beyond the scope of most DIY wrenchers here.