Need advice on a good deck & adaptors to integrate with factory JBL amp!

[DerekTheGreat]

Hey everyone, I've got a question I was hoping you guys could answer.

My 1988 Townie originally came with the standard premium sound system. I upgraded the amp, door & rear deck speakers to factory JBL stuff (Door speakers are from a Mark VII) and now want to upgrade the factory deck as it's fidelity sucks. Girlfriend has the same set up in her '89 but with a newer Pioneer deck, so far no problems with running the stereo's internal amp through the JBL unit- sounds great, nice and punchy!

I want to drop in a Pioneer DEH-X6500HD or Alpine CDE-HD149BT or Kenwood KDC-X998 but want to know if someone makes a plug and play harness so I can send line-level inputs to the JBL amp instead of an amplified signal. I really want to retain the JBL amp. After some searching I found this and got a glimmer of hope with it..

Yes, amp in the trunk, can possibly be bypassed with a harness but no promise on that. the 88+ radios are different than prior years, and they are Lincoln specific as well as far as I know. Vic radios don't have all the same plugs since they didn't get line-level outputs like the Lincoln radios.

Please take a look at these harnesses, which one should I go with?
-This one looks like a PITA and low quality but at least I could adjust the level going to the JBL amp.

http://www.crutchfield.com/p_142C4FDK5/Scosche-C4FDK5-Wiring-Interface.html?tp=3486

-I can't find it anymore but I really want something that will adapt the harness going to the JBL amp into 4 RCA's that I could just hook-up to the back of the reciever... This isn't the correct one but you get the idea. Does someone make it for our cars?

http://www.crutchfield.com/p_120GMRSAV/Metra-GMRSAV-Factory-Integration-Adapter.html?tp=3486

Also, what do you guys think about the radio choice? I've always been an Alpine dude but when we got Ashley's Townie the previous owner had just dropped a Pioneer in it. I liked it's loudness feature (which Alpines do not have) because it boosts bass at lower volumes which makes it sound that much better and I find myself not cranking up the volume as much, so I'm kind of leaning towards a Pioneer now. But, I hate their lack of buttons! I want 1-6 for presets and forward & reverse buttons dammit! Only Alpine shines in that department. So your thoughts are appreciated.

Thanks,

Derek

[DerekTheGreat]

What, no replies? C'mon fellas!

I think I found the harness I'm talking about...

http://www.sonicelectronix.com/item_4455_Scosche-FD03B.html

That should adapt the square plug connector that runs to the JBL amplifier into RCA inputs right? Or does my 88 not have that set up? I haven't ripped it out of the dash yet to see.

This one here I think is the package deal I need to take care of the re-wire job..

http://www.sonicelectronix.com/item_12649_Metra-70-5510.html

What do you guys think? Seems to be like the first one plus the extra adaptor for the power supply and what not. Will this fit the bill for what I'm trying to do??

Thanks,

Derek

[IPreferDIY]

I've never dealt with one of these, so I can't help with the wiring stuff. I've seen people on here say good things about the premium sound system, so I'm figuring you either insulted them with "it's fidelity sucks" or they've never gone through the process and have nothing to offer.

As for choice of head units, unless you have buckets of money, it's just one of those things where you have to figure out what fits your personal tastes. I went through a phase of picking up a bunch of used ones for cheap, and I can't say that any stood out as being "clearly superior" to the others; though if you go with Pioneer, you should see if they have something available from the Premier line. Personally, I've yet to find a head unit that totally blew me away. Something like that would probably cost buckets of money.

[sly]

Ditto that... mainly gadget and 86vicky are the go-to JBL guys... you'll have to wait for one of them to chime in.

you could also search www.crutchfield.com for the JBL adapters. poke in your year/make/model/jbl system in the "what fits my car" stuff and look at the installation stuffs. should be in there.

[gadget73]

Either the Metra 70-5510 or that Schoche should work. I have that Metra kit in my Mark VII with a cheapo freebie Sony stereo and it talks to the JBL amp just fine. You do need both connectors to plug in properly. The plug on the RCA jacks is a bit shitty on it though, so you will need to be extremely careful plugging it in. I had to carefully wiggle the wires to get the pins to line up. I think one did pop out at one point but it clicked back in OK.

The Mark VII door speakers are probably not any different than the Premium door speakers. The magic is in the 6x9 trunk speakers, which are actually specific to the Mark VII or Towncar, depending. The Townie ones are close, but the pods are angled differently due to the rear window being different. Unless you're way OCD about it, you'll probably never know. I just happen to own both a Mark VII and I have a proper set of Towncar rear speakers so I know they aren't the same. Towncars also had a specific JBL dash speaker, but they're all shot by now. I wouldn't get concerned about finding that. Any decent quality dash sized speaker will do the trick better than a 25 year old paper cone that is turning to dust. The rear JBLs had a composite cone with a rubbery surround that holds up well. The midrange is paper though, and half the time they are gone. I haven't looked into how to rebuild that speaker pod yet, the one on the Mark VII was dead on one side and rattling on the other. I removed the rattling cone with a pocket knife to stop the rattles. Its got a hole in the midrange if you sit in the back, but you don't hear it from the front. The rattle was way worse than the hole.

The other hitch is that the JBL amps die sometimes. The output chips apparently have some sort of failure mechanism that is age related. Paul Protos told me that NOS versions of those chips are often found dead, but never used. They can be replaced with a newer chip that doesn't seem to be problematic though. Paul sent me a set of them to fix one of my amps.

[DerekTheGreat]

Either the Metra 70-5510 or that Schoche should work. I have that Metra kit in my Mark VII with a cheapo freebie Sony stereo and it talks to the JBL amp just fine. You do need both connectors to plug in properly. The plug on the RCA jacks is a bit shitty on it though, so you will need to be extremely careful plugging it in. I had to carefully wiggle the wires to get the pins to line up. I think one did pop out at one point but it clicked back in OK.

The Mark VII door speakers are probably not any different than the Premium door speakers. The magic is in the 6x9 trunk speakers, which are actually specific to the Mark VII or Towncar, depending. The Townie ones are close, but the pods are angled differently due to the rear window being different. Unless you're way OCD about it, you'll probably never know. I just happen to own both a Mark VII and I have a proper set of Towncar rear speakers so I know they aren't the same. Towncars also had a specific JBL dash speaker, but they're all shot by now. I wouldn't get concerned about finding that. Any decent quality dash sized speaker will do the trick better than a 25 year old paper cone that is turning to dust. The rear JBLs had a composite cone with a rubbery surround that holds up well. The midrange is paper though, and half the time they are gone. I haven't looked into how to rebuild that speaker pod yet, the one on the Mark VII was dead on one side and rattling on the other. I removed the rattling cone with a pocket knife to stop the rattles. Its got a hole in the midrange if you sit in the back, but you don't hear it from the front. The rattle was way worse than the hole.

The other hitch is that the JBL amps die sometimes. The output chips apparently have some sort of failure mechanism that is age related. Paul Protos told me that NOS versions of those chips are often found dead, but never used. They can be replaced with a newer chip that doesn't seem to be problematic though. Paul sent me a set of them to fix one of my amps.

Thanks gadget! Very detailed..
I'm a JBL fanatic. Amps are hard to come by but so far the 2/3 we found are working great. The one played the drivers side rear funny, I took it apart but nothing looked burned up so I trashed it in anger.. There are differences in the door speakers, the MarkVII's are two ways with a little tweeter (paper) mounted in the center and the magnet is of different size, deeper but not wider than the Town Car JBL unit. So far I've only been able to locate one working town car door speaker and four Mark VII speakers. I found out the rears are different the hard way, so if you want extra JBL 6x9's let me know. The VII ones have foam surrounds for the spiders and are always shot. What a shitty design that is. The earlier JBL rears used rubber or paper surrounds which are still holding up. I've got a rattle in one of mine though.

Great news about those harnesses, I'm getting excited, might have to pull the trigger soon and buy audio gear! You guys have any words about stereo choice??

Thanks for your advice and suggestions!

Also, I want JBL stuff! If you got it let me know..

[piranah]

The town cars are very picky, as I am learning, unless its just a 1990 Townie issue.

I have had to have Crutchfield send me three different harnesses to try and get my aftermarket stereo working correctly. If you want to avoid a clicking when you change the station, you will need a 12 volt to 5 volt adaptor. When I hooked that into my stereo, I lost sound in the speakers. Now I am waiting for a ground isolator to hopefully get it working.

[gadget73]

If it plays one channel funny, its a fair bet you have a dead chip. Without getting overly technical, basically the bulk of the amplifier is in one big circuit chip. Each chip runs 2 channels, so one for front and one for back. Those chips can die shorted or open. When they short, it pulls huge current and blows fuses. If open, either a channel is dead, or you get half of the audio signal, either positive or negative peaks only. I've had them go both ways. There are 3 of them here that had dead chips. I fixed one as a spare, the others are parts donors.

[piranah]

Where can I get the chips? Is there a write up on replacing them?

[DerekTheGreat]

If it plays one channel funny, its a fair bet you have a dead chip. Without getting overly technical, basically the bulk of the amplifier is in one big circuit chip. Each chip runs 2 channels, so one for front and one for back. Those chips can die shorted or open. When they short, it pulls huge current and blows fuses. If open, either a channel is dead, or you get half of the audio signal, either positive or negative peaks only. I've had them go both ways. There are 3 of them here that had dead chips. I fixed one as a spare, the others are parts donors.

Ah man, I wish I joined this forum a bit sooner, could've saved that amp maybe. Was in better shape than the one I've got now.. What does that chip look like and where can I get new ones?

piranah, Ive got a spare JBL amp for your car, works great. Let me know if you want it. I found out they aren't a good fit cor the older stuff.

[gadget73]

Its an STK 2240 chip that dies. You can replace it with an STK 2250. Not really any writeup but it involves a bunch of desoldering, removing a lot of screws, physically swapping the part, then re-assembling. If you've ever done any kind of circuit board repair work, its not a big deal. If you don't have the tools to do that, I would advise not fooling with it. Its not the only thing that can potentially fail, but its the part that has been dead in my several JBL amps.

The original part was good for 40 wpc, the replacement is rated to 50, but the power supply in the JBL amp will limit it to 40w. That may help it last a little longer since it can only be pushed to 80% of maximum. They will do a solid 40 watts RMS per channel too.

[DerekTheGreat]

Thanks gadget, I'll keep that in mind if what we've got fails or if another one we pick up plays the same way. Forty watts is solid, its good enough for what I'm doing and coupled with those rears is very punchy. You'd be hard pressed to find better speakers and I've listened to quite a few. My favorites are JBL's power series, dynamic true sound with real power handling.