Replacing speakers on stock Premium Sound--possible?

[DerekTheGreat]

Hmm, when I rip apart her dash to fix that noisy speedometer I'll see if her kit has a number on it..

That's awesome Ford did it that way, has to be the easiest "option" you could add. I even swapped out her speaker grille badges to complete the look I intended to do same thing with my 88 but the badges don't mount the same way so I gotta find the older style mounts but not older style logo, if that's even possible.

When you say input voltage you're talking about the pre outs right? Maybe that's my issue. I always thought higher is better and means a lower noise floor. The deck I've got is 5 volts. I could just feed the thing line level inputs like Ashley's TC and get the volume I want but the amp in this thing is rated higher than hers, that might set the magic smoke free. I remember you saying that the chips on those JBL amps go bad.. I wish I knew that before I pitched the nicer looking amp away. That amp worked great except for the left rear channel, which was static central.

[gadget73]

If you have 5v output, that should be absolutely no problem driving a working JBL amp. The stock setup will hit full power output well before the 5v signal input level. I have notes around here somewhere but its around 1 volt signal input to get full chooch on the output. Beyond that it will just distort horribly.


The chips aren't real hard to replace if you have a new one. It does want a desoldering iron though or you'll have a bitch of a time with it.

The JBL amps have a very non-flat frequency response too. There is a fat hump in the upper bass region and it rolls off sharp under that. The whole thing was tuned to match the speaker system and probably to some extent the car itself. I remember comparing a Mark VII amp to a Towncar one, and they don't respond quite the same. I wish I had spent more time and made a proper frequency chart of it. Maybe someday I'll put the extra set of chips I have here into that dead JBL amp and see what it tells me. I don't remember if its a Mark or a Towncar amp though.

[DerekTheGreat]

Hmm. Perhaps that's why I'm not getting the volume out of the thing. There's no distortion ever but if I try to listen to the radio or Alice Cooper it's just too low, even at full volume. Louder stuff like Alcholica or AC/DC becomes fairly loud.

I should've kept it, the case was really nice and even dead ones are worth money to some people. I've just got too much junk.

I can tell there's an emphasis on bass for sure, especially when going from the stereo's internal amp to the JBL amp- which is why Cash & T.Rex sounded so good haha. Makes using the loudness feature on that Pioneer impossible though. Did not know there were differences between TC & Mk.VII amps though, do they have different part numbers?? This further supports the aftermaket amp, flexibility & tune it yourself are nice to have.

[gadget73]

There are different part numbers, though I couldn't tell you which is which. There are several different ones on just the Mark VII, though I think its just the year code that changed. Maybe if I get ambitious and put together a stockpile of JBL amps I'll assemble test data from them for comparison. I wouldn't have figured there was any difference either until I tested one and found that there was.