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Discussion Starter · #1 ·
Does anyone know where the stereo amp is located on an 88T. According to the shop wiring manual there was an option for a component amp, and it kinda sorta appears to be located under the passenger front seat. I can't find the damn thing, but I only have 1.5 ohms at the speaker connectors at the stereo on 4 ohm speakers so I'm wondering if there is another location.

Thanks
 

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blusup said:
Does anyone know where the stereo amp is located on an 88T. According to the shop wiring manual there was an option for a component amp, and it kinda sorta appears to be located under the passenger front seat. I can't find the damn thing, but I only have 1.5 ohms at the speaker connectors at the stereo on 4 ohm speakers so I'm wondering if there is another location.

Thanks
I think it was only an option on 91 models... you need to ask Mr. J. Lange
 

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Yeah, not a pre89 option.... at least I don't recall it in my 88 TSRM or TEWD. I'd double check, but my car's out for the night...... damned wheel bearings.
 

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Madd Tyte JDM yo ®
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wait, what?

are you saying you installed new rear speakers, the new ones being 4 ohm?

the rear speakers are 4" with smaller tweeters. the impedance is going to be lower on the rear channels since the stock speakers are 8 ohm. so if you install 4 ohm speakers, of course the impedance is going to drop.

if you had a stock speaker amp, youd see the extra connectors/harness in the dash when you pull out the head unit...even if you cant see the stock amp under the passenger seat.
 

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Dr. Jeff Lange
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porn-adkt said:
I think it was only an option on 91 models... you need to ask Mr. J. Lange
It is common on 89+ models, but was available starting in 1988.

CRE said:
Yeah, not a pre89 option.... at least I don't recall it in my 88 TSRM or TEWD. I'd double check, but my car's out for the night...... damned wheel bearings.
Look again, you'll see in the TEWD a component amp and CD player in the 1988 book.

I've never seen it in real life, but the CD player/amp was made an option in 1988 models.

That being said, if you have the harness behind the stereo that is going to the speakers, etc, the amp is not in that circuit. What happens on cars with the amp is that the harness that normally plugs into the radio plugs into an extension harness instead and that runs to the amp under the seat. There is then another harness that runs from the amp to the head unit.

If you do not have this extension harness, you do not have the amp, if you are looking at the typical Toyota connectors, with output to the speakers, that will always be high-power wiring directly to the speakers.

Measure the impedence right at the speaker, then measure it at the head unit wiring, speaker impedence is not constant.
 

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Madd Tyte JDM yo ®
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yeah... the resistance would be different measured at the back of the radio and then measured at the terminals on the speaker enclosures.

the rear enclosers integrate the factory tweeters. so installing aftermarket speakers w/ a lower impedance rating than the factory mids will yeild an overall-lower impedance. the rear speaker enclosures are wired in parallel, mids and tweeters on the 8 speaker system.

on the 10 speaker system, there are 2 more mids at the rear passenger's shoulders. those are 8ohm impedance as well, since they are all run off the same channel as the mid and tweeter in the hatch enclosures.

if you use aftermarket 4" and 3.5" w/ the factory tweeters, i want to say that the impedance will drop to 1ohm, if not less. hmm, it didnt occur to me untill now. my impedance may be too low for my aftermarket amp that i have installed to run my rear channels. ive installed a full set of Infinity Reference's, but i havent changed the factory tweeters in the stock enclosures. i hope it sounds bad ass...w/o melting down my amp.
 

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Dr. Jeff Lange
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Flubyux2, the pre-89's only had 4 speakers. 2 in front, 2 in back. There are no speakers wired in parallel with the ones he has installed. Also, IIRC, (but not confirmed by any means), I think I recall my stock speakers being 4 ohms when I pulled them out.

(It would make sense, since if they went to 8 ohm speakers in 89 with them wired in parallel it would make the overall impedance per rear channel 4 ohms).
 

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Jeff Lange said:
Flubyux2, the pre-89's only had 4 speakers. 2 in front, 2 in back.
:bowdown: :bowdown: :bowdown:

It returns... my memory from hell.... I was thinking of the wiring diagram for the 6 speaker setup. :ugh2:
 

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Madd Tyte JDM yo ®
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jeff... i figured as much. i didnt recall finding the 3.5" mids on the rear passenger shoulders behind the trim panels. but my 87 turbo definitly had a bose system w/ tweeters in the rear enclosures. i think the door enclosures were mids and highs too. also bose units. i took them out and so i had something to install in the other 89 that i stole the infinities from.

im just trying to think of how im going to run 6 speakers off one amp. does anyone know what the impedance of the 89+ tweeters are?

ive got
3.5"- 4ohm
4.0"- 4ohm
tweeter= ?ohm

they are all run off one channel per side... and im afraid my overal load is going to be 1ohm or less... i dont want my cheap old alpine amp to melt down.
 

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Discussion Starter · #10 ·
Thanks to all. I can't figure whats going on. I had a 10 year old Pioneer head pushing the stock speakers whith cones that had basically disintegrated. So .... I put in four new 4" Hertz speakers which obviously improved the sound over the disintegrated stockers ... but still not great. According to the gurus at two reputable car audio shops the the next step was the deck head. so, I bought a Kenwood KDC-X590, hooked it up and got very faint distorted sound with the volume cranked. Back to the stereo shop where they said " you must have an amp in there somewhere and you've blown the ICU's on the deck. Tore the car apart looking for an amp .... but no amp to be found. Back to the stereo shop to get another deck ..... same result. I now have a third deck and I'm afraid to hook it up. Guess I'll try to get everything working on the bench and see if I can find out why the deck keeps blowing. Right now I'm not real impressed with Kenwood or East Hamilton Radio, but still not 100% positive that there isn't something goofy going on at my end.
 

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