jrp

Hello All,

I purchased a new to me 1995 Cab about 4 months ago. Have been browsing threads, and have learned lot. Especially sensitive to posting without using the search function, so I searched and searched, but cant seem to find an answer.

Car details: Non-Premium sound, tape deck, no CD changer.

When I picked up the car, the front speakers did not work at all(aftermarket coax). Don't need great sound, just need working speakers so I had planned to replace the non-working speakers with working ones. When I took the panels off, I noticed that the speakers didn't work because they were not connected! So I connected them(ofcourse the tweeters are out of play here) and they worked! I thought I was done.

Then I realized the speakers work, but after 10-15 minutes of driving the sound becomes horrible. Initially, I just contributed this to poor radio reception(I have read all the poor radio threads and checked the connection accordingly). But the more I drove, I realized it always starts out great and then gets bad after a little time. I tried turning the radio off and on again to see if it helps, but it does not. If I turn the car off and then turn it back on, the sound gets better again. Now, I am no automotive expert, but that seems like an electrical problem rather than radio reception problem.

Has anyone come across this, or does anyone have any suggestions?

Other than this, the car is fantastic. I have updated the shocks(koni FSD), changed out the bushings(ER), ordered CW aluminum gauge rings. The motor is strong and the drive is great. It is very easy to keep the radio off, but not knowing the problem is bothering me.

Any help would be helpful.

Kika

Does the sound quality diminish with time using a tape as well? (assuming anyone still has a tape around to test)

If only the radio, I would suspect the tuner may have issues and is losing frequency lock. if both the radio AND tape go bad, then I would suspect something in the amplifier is heating up and generating noise.

Unless you really want to tear the unit apart and do some electrical trouble shooting, it probably doesn't really matter, which is the problem and the best solution is simply to get a new headunit.

It could be that the speakers are bad too, but speakers are passive devices and having a time component would not point towards the speakers having an issue. If they are the original Nokia speakers, they are likely dry and shot , and I would suggest replacing them anyhow.

it is possible that some connection is not good also, but if the system is factory, I would kind of doubt that. It would be more likely if an aftermarket system were installed and the installer was not very good. It does sound like one of the previous owners disconnected the speakers, although that is odd too, I would simply not turn on the radio and achieve the same result.

Do you know if any previous owners did something to the sound system?

jrp

Funny you mentioned about testing with a tape. That was my first thought as well. But I couldn't find any tapes, and the dude at best buys laughed at me when I asked about cassette tapes.

From what I can tell, with the exception of the aftermarket coax speakers everything is stock. I tried other wider searches, that said something about poor grounding as a possible, but have no clue how to address that.

Kika

The nearest you might get in this day in age, is one of those cassette to mini plug adapters, which would actually suffice for these purposes.

poor grounding is usually associated with alternator whine, which is a high pitch noise that leaks through the system through ground loops (bad or mismatched grounds) and vary with RPMs. It is most common with high power (100W RMS and up) as small noises are amplified though the system. It does not seem like this is your problem.

Since you mentioned Best Buy, I definitely would not have any installer there work on my car. If you want a quality install you need to go to a specialist.

Assuming you have a CR-210 Becker radio, it is not all that difficult to remove from the car. You can remove it and take it to a car stereo shop and have it bench tested. They should be able to apply 12V, and hook it up to some speakers and see if the problem replicates outside the car. if you have a little electrical know how, it isn't terrible difficult to do in your garage either.

Chris V

I have the cassette soundtrack from Purple Rain....not using it at the moment if you want it

jrp

Chris V: Thanks for the offer on the tape, but I will try the adapter route first.

Agreed about best buys not working on the audio system.

pp000830

A quick speaker check is to measure the impedance of each speakers at the plug behind the head unit. It should be between 4 & 8 ohms. If lower or higher the speaker's coil is suspect. If you attach a 9 volt batter to the speaker wires behind the radio leading to each speaker and cycle connecting and disconnecting the battery you should hear a nice clean pop with no rattle or buzz. This assumes you do not have the power amp under the passenger seat. If you see one there testing is even easier as you must unplug the power amp under the seat and do the testing at its connection points
If the impedance for a speaker is below 4 ohms you may be overloading the power amp causing noise as you turn the volume up while running the engine.

A suitable ohm meter is a few dollars at Harbor Freight.

Hope this helps,
Andy