fm928

I got a new Pioneer DEH 80 PRS head unit from Linda for Christmas. I hope to just run it into the factory speakers minus the Porsche amp. But the installation manual (https://www.pioneerelectronics.com/S...nual072616.pdf) states:

"Use speakers over 50 W (output value) and between 4 Ohm to 8 Ohm (impedance value). Do not use 1 Ohm to 3 Ohm speakers for this unit.".

My 928 is a 1985 S with the eight speaker system. The rearmost speakers are 2 Ohm. But according to the wiring diagram, these 2 ohm rear speakers are wired in series with the low range back seat speakers. So the impedance of the circuit should be greater than 4 ohms.
1. Has anyone used this Pioneer head unit with the factory speakers?
2. If the circuit impedance is between 4 and 8 Ohms would there be a problem?
thanks.



928S speaker wiring diagram

Billu

I’ve been looking at this receiver for about 6 months, thinking it should look right in the 928.
please post pics once installed.
Since resistance in series is additive, should work just fine.

bureau13

I have it, but my center console isn't really installed properly, I've still got some issues, so a pic wouldn't be helpful. IMO the glossy black plastic finish of this head unit doesn't match particularly well...would be better if it were more of a flat black.

ThetaTau87

Here's what it looks like in mine. The gloss black isn't a great match, but it doesn't look too out of place IMO. It has a simple design (unlike most new head units) that isn't too flashy, just functional. The changeable LED lighting color is key to making it blend into the dash. The pre-set orange color is a great match for the rest of the screens in an '89+ 928 with electronic dash. I like this unit so much I have a 2nd one in my Audi. It's SO nice having the same controls in both cars. Jumping between the different shift patterns and reversed speedo and tach is enough, I don't need to have completely different radio controls as well.

Shots taken with and without flash because she's currently sleeping in my dark garage and it's 0 F outside. She won't see sun again until April.

bureau13

I do agree about the customizable colors. I have mine on green (for button lighting) and "coral" for the display. Looks great at night. I also love Pioneer's auto-config to set it up for your car and your driving position. The UI is weird though...I still can't figure out how to manually find any particular FM stations

To get back to the OP's question: If the two sets of rear speakers are indeed 2 ohm speakers wired in serial, then it should be no problem. Might be OK anyway, I'm not sure...I do know that when I changed out my speaker, I just left those hatch speakers disconnected. They cannot possibly be good for your sound stage...

fm928

Thanks Jeff, but those are the only speakers close to ear level so I don't think they can hurt. Without them the impedance may be too low. I will go ahead and install and let you know the results.