Sudden bass dropout on radio?

[tjenkins]

My 90 coupe works fine, however, the other day, the (non-Bose) radio (and CD-Player) seem to just 'loose' the bass response. I have turned up the graphic equalizer, but it just doesn't have the 'presence' that it once had. I've been driving it 2 years, and all of a sudden, the frequency response seems somewhat 'tinny'. It is hard to describe, but its like turning down the tone control.<P>This is with all four speakers (actually 6), and I've verified that the radio is still in stereo (not mono).<P>Anyone have any ideas?<P>--Tom<BR>

[Guest]

Did you check the "Fader" (forward/aft/left/right) setting? Have no idea how it could have changed but if every thing is still hooked up and the radio settings are OK it's the only thing that pops into my head just now. Another thing is try more than one station. As I tell the people I give tech support to, I had to say that [because you didn't]. You probably did this but sometimes they are messing around with the transmitter and the audio quality goes to hell while they are at it. <BR>You ever live around Sacramento CA?<BR>Robi

[tjenkins]

Thanks for the commens. Yes, I ensured both the fader and right/left were correct and centered, and indeed, switched to several FM stations. Even AM sounds rather trebleish.<P>If that makes sense.<P>--Tom<BR>

[TheBlackMoon]

Hey Tom, <BR>You have close nil (none, zip, nada) bass in the front 4 speakers. The rear dual cones are what supplies what bass you hear. When I installed the new system with subs, I suddenly began losing bass intermittenly, though the amp worked just fine. Rears were not hooked at the time and all came through the box (external version of what you're dealing with). The daggone voice coil of one of the subs had blown and the other wasn't far behind. I still got perfect mids and highs, but absolutely zero lows. If you can, try tapping your rear speaker wires and hooking up external ones. (PepBoys, Autozone, and Parts America all sell a little blue in-line tap that's great for this as you can tap the wires without cutting the insulation or splicing then). If the speakers work fine, it's your voice coils. Replace the rears. Otherwise, there's another possibility I'm aware of (had quite a few surprises when I replaced that head unit). Email me and I'll give you details. Simply put, it's a bad ground on the front speaker (yes, I said front ) <BR>LOL

[tjenkins]

Thanks for the post. Yes, it certainly ounds like the bass has dropped off the rear speakers. I looked through the manual last night, and found that the two rear speakers are on their own circuit, and appear to be one voice coil. Since this happened rather suddenly, I don't think that just one bass voice coil went, if there is a split bass/treble voice coil inside the rear speakers.<P>Regarding a front missing ground - please pass on the details..<P>I did in fact remove and replace the right rear speaker, but the sound appeared to be the same. The original OEM speaker was in good condition, with no breaks in the cone etc. In other words, the reason for the loss of bass or 'presence' seems to not be the rear speakers.<P>If I had another radio...<P>I had another thought - does anyone know if I unhooked the battery for 30 minutes, and reset the controllers/computers, would that help?<P>--Tom<BR><p>[This message has been edited by tjenkins (edited 07-22-2000).]

[tjenkins]

Problem fixed! I reset the computer, by removing the battery lead for 20 minutes, and viola - it works!<P>I now have all the bass and treble back - amazing!<P>--Tom<BR>