Replacing Pioneer Stereo Receiver

[Tim Schafer]

The Pioneer unit in my patriot has been flaky at best, non working primarily.

I pulled it out last night with the intention of just replacing it with an identical model I found on ebay, but was curious if anyone had found one they liked better.  (This would be from a mid 90's unit).

I'm a bit worried about the speaker system, they appear to be car speakers in the ceiling, which would be 4 ohm, and the HT stereo's normally want 8 ohm speakers.  There is some sort of blue box that the speaker wire's from the receiver fed into, the dash stereo also feed into it and then it appears to feed the speakers in the ceiling and bedroom.

Does anyone know what the blue box does?  Is it a 4ohm/8ohm converter?  It does have a 12v power wire running into it, so it's powered for something, but there are no labels or markings on it identifying what it is.

Just curious what others have done as far as upgrading their home theater systems.

Thanks for any info you can provide.

Thanks,

Tim & Ann

[Edward Buker]

Tim,

I'm not absolutely sure of this but it may be an isolation unit (may be relay based or solid state device based) that looks for 12V from the ignition and if it has it, it switches over to the dash radio for a speaker connection. If it does not see 12V then it will connect to the HT system. You could test that by applying and removing 12V to see what it does. This would prevent either unit from feeding output into each other. 8 ohms vs 4 ohms should not be an issue for either unit. The output stages are tolerant and protect themselves, just power output may be reduced at 8ohms vs 4 ohms given solid state amps usually like the lower impedance. This is the only reason I can think of for two units speaker output being fed this way....switching.

Later Ed