JBL Factory Amp Idea

rayner601

rayner601

Dedicated LVC Member
Joined
Aug 4, 2007
Messages
615
Reaction score
0
Location
Philadelphia, MS
I disassembled the discarded JBL amp in my 97 base last night and looked up the specs on the output. For the 4 5x7 speakers they are run by 2 1 channel 45w amp chips and the 4 3.5 speakers are ran by 2 2 channel 30w per channel chips. I have also figured out how to make very cheap (basically free since all the parts needed to make the amp are already there) amp that won't cut the bass like 90% of the Ford head units and amps do. If anyone is interested, I can supply directions free of charge.
 
I'd be interested in any information that you have about the JBL amp.

PM sent.
 
1 of the caps in mine (6.5v 330 mf) leaked and my amp is shot.
fkn rubycon caps. same thing in early 90s mitsubishi ECUs.
 
i am not ready to mess with my amp right now,but would like the info sent to me for a later time,
thanks
 
Thanks for the info Joe. I've been trying to find a schematic for the JBL amp for a while now but I haven't been able to find one.

These data sheets for the amp chips helps a lot. At least I have an idea what I'm looking at now.

I've got 2 bad JBL amps and I'm trying to fix one with the parts from the other if possible.

Thanks again!
 
Sounds interesting...

I've been playing with my system but I have the stock $hit...not the JBL..

I've put the JBL tweeter in but need a new amp and to re-wire my system. Also have put in some 6.5" infinity rounds for those 5x7 units.
 
My amp was shot, I went to have it repaired. They said it was too far gone, and I ended up getting a rebuilt one for $200. I think I got screwed
 
rayner601 said:
I disassembled the discarded JBL amp in my 97 base last night and looked up the specs on the output. For the 4 5x7 speakers they are run by 2 1 channel 45w amp chips and the 4 3.5 speakers are ran by 2 2 channel 30w per channel chips. I have also figured out how to make very cheap (basically free since all the parts needed to make the amp are already there) amp that won't cut the bass like 90% of the Ford head units and amps do. If anyone is interested, I can supply directions free of charge.
Click to expand...

I'd love to get the info. You wouldn't happen to know the crossover specs would you? The stock setup has sort of a mid-range/mid-base rumble that's quite annoying.. I'm thinking of replacing the stock speakers with the Infinity Reference Series 6820CS's and want to make sure I'm matching up the tweeter frequency ranges. OR If you guys have better recommendations please let me know :)
 
You don't need an amp. I had my entire system replaced with a new receiver/cd player for less than $300 and it doesn't have some big clunky amp, and the sound is better. Technology has advanced far beyond 90s vintage. Just get a new stereo put in, that's all you need.
 
I think that some people want to keep the factory stereo. Mine sounds very good and clear + it has the 10 disc cd player as well. A factory JBL amp can be bought for $20 bucks at the local pic a part so if mine ever does go out it's easy enough to replace.

90's Vintage??? LOL!
 
As Fossten said. Hi - Fi electronics, like computers have come along way since the early 90s. Would be nice to get a powerful, high quality head unit with an I pod connection, lose the factory amp and gain some much needed trunk space.
 
Just how much trunk room do you think you will gain by removing the JBL amp? Likey not any since it sits in the tray under the rear deck along with other componets as well.
 
Tboneguy said:
I'd love to get the info. You wouldn't happen to know the crossover specs would you? The stock setup has sort of a mid-range/mid-base rumble that's quite annoying.. I'm thinking of replacing the stock speakers with the Infinity Reference Series 6820CS's and want to make sure I'm matching up the tweeter frequency ranges. OR If you guys have better recommendations please let me know :)
Click to expand...

I am thinking crossover point is around or just below 1k...The speakers aren't really the problem, it's a lack of power from the amplifier. In my car I have a Kenwood KDC-X889 with the factory speakers and it sounds pretty good to me, 100x better than the factory system. I also have 2 Infinity 12" subs with a 300w amp on them.
 
turborich said:
Just how much trunk room do you think you will gain by removing the JBL amp? Likey not any since it sits in the tray under the rear deck along with other componets as well.
Click to expand...

When i do remove the amp the shelf will go also. That package tray protudes into the trunk's useable space by over 9cm. With that gone i can fit one small suitcase upon another. What other components are on that tray? Just amp, phone module and compass module isnt it?
 
rayner601 said:
Toshiba Chip Datasheet--- http://www.datasheetcatalog.com/datasheets_pdf/T/A/8/2/TA8221AH.shtml

NEC Chip Datasheet--- http://www.alldatasheet.com/datasheet-pdf/pdf/84779/NEC/UPC2500AH.html

The NEC chips run a pair of the 5x7
The Toshiba runs a pair of the 3.5

There's also an optocoupler that compresses the volume above half way. It is a small black can looking thing that has vactec on it. Should be able to cut a lead on the led side of it to defeat it. I haven't tried that yet though.

Joe
Click to expand...

That optocoupler might control the automatic loudness feature that comes with the JBL system. The automatic loudness controls the ratio of bass to treble as the volume is increased or decreased. Without the loudness control, when you turn down the volume, you hear less bass compared to the treble. This is because of the way our ears are less sensitive to low frequencies at lower volumes.

This is one of my favorite features of the JBL system. I don't have to change bass and treble controls depending on the volume.

I love the JBL system too. It could use a little more low bass, but that's easily fixed with the addition of a subwoofer.
 
i loved the jbl sys with my cheepie sub set up, that is till the speaker cones slowly disintegrated one by one, so out with the old and in the new :D but now im lacking "some" trunk space
 
93' Blue on blue said:
When i do remove the amp the shelf will go also. That package tray protudes into the trunk's useable space by over 9cm. With that gone i can fit one small suitcase upon another. What other components are on that tray? Just amp, phone module and compass module isnt it?
Click to expand...

Are you taking that stuff out as well? If so then I guess you will gain 9 cm. Not too much room gained though. Are you going to use a new amp? Where will you install it at? If you don't need the items in the package tray then this may work out good for your particular need to fit one more suitcase.


While we are talking about the JBL amp, Does anyone know which wires on the amp go to the rear speakers? I want to run them to a amplifier in my buddies Mark to run a couple of 10's. He has been wanting me to do this for a while now, I just don't wanna mess anything up.

Thanks.
 
turborich said:
Are you taking that stuff out as well? If so then I guess you will gain 9 cm. Not too much room gained though. Are you going to use a new amp? Where will you install it at? If you don't need the items in the package tray then this may work out good for your particular need to fit one more suitcase.


While we are talking about the JBL amp, Does anyone know which wires on the amp go to the rear speakers? I want to run them to a amplifier in my buddies Mark to run a couple of 10's. He has been wanting me to do this for a while now, I just don't wanna mess anything up.

Thanks.
Click to expand...

what year you lookin at? i originally tried this and ran into all sorts of problems. later i found out 1 of my problems was the amp turn-on signal for the stock amp was only 5 volts, but i still couldn't get any sound. you could just tap into the wires off the back of the speaker and run them back, trust me your back will thank you
 
turborich said:
Are you taking that stuff out as well? If so then I guess you will gain 9 cm. Not too much room gained though. Are you going to use a new amp? Where will you install it at? If you don't need the items in the package tray then this may work out good for your particular need to fit one more suitcase.
Click to expand...

Well, my amp doesnt always work properly, my Ford tape head unit likes gospel music and the mobile phone module is defunct so will eventually remove those items. The compass module can probably stay or be moved. My plan is to get a nice head unit for I pod, strip the interior and run all new wiring / speakers without use of a separate amp. Will put some dynamat in also. (all this when the $$ permits - Lol)
 
turborich said:
Are you taking that stuff out as well? If so then I guess you will gain 9 cm. Not too much room gained though. Are you going to use a new amp? Where will you install it at? If you don't need the items in the package tray then this may work out good for your particular need to fit one more suitcase.

Thanks.
Click to expand...
I think he's talking about replacing the stereo with something not from the stone age. Doing that means no new amp is needed.

I don't know about trunk space, but the fact that I've had a great new stereo and CD player for 2 years without a big clunky amp ought to give somebody somewhere an idea. It cost a lot less to replace the entire stereo than to fix/replace the useless amp, which by the way would still leave the system underpowered compared to today's systems.
 
You must log in or register to reply here.

Members online

No members online now.
Total: 212 (members: 0, guests: 212)
Back
Top