View Full Version : Quality ICE Install ??????????

30-10-01, 08:54
Hi Guys,

Went to local Car Audio installer to get a new sony head unit,
single din + cubby hole........

Hmmmmmmm was offered discounts of 50 quid here and there
but nothing special.

Then i saw the price of SONY head units - wow - did not realise
how much of a discount we got on high-street prices.

So, I told him i'd source the head unit my self, and everything changed :
now i have to pay 50 quid for fitting,
50 quid for a special "harness" (??) to bypass the stock amp
30 quid to get a cubby hole
and "a bit of money" for any special connectors required.

Upshot of this is, i'm probably going to fit it myself
although the head unit I am going to get (CDX-CA850 - 189.47quid)
has a 1xsubwoofer output and 2xpre-outs.
anyone know what this means?
and how would i bypass the stock amp to wire up all the speakers
directly??? (and where is it?)

plus, what size are STOCK front, rear and subwoofer speakers?
and how the hell do i get to the stock sub to replace it??


30-10-01, 09:49
Subwoofer output is just a bass signal. There should be some control for this in the head unit that allows you to adjust the level.

Pre-outs are what you use to feed another amplifier. It sounds, from what you say, that the head-unit already comes with a 4-channel amp built-in which you want to connect to the stock speakers. But if at some stage you wanted to have additional speakers, fed by another amp, then you would feed that amp with the pre-outs

The speaker wiring terminates at the amplifier which is located under the passenger seat.

Not sure what you mean about "stock front and rear subwoofer speakers.

Some cars have a subwoofer box located immediately behind the rear seat. There are four other general speakers, one in each door and one either side of the rear seat.

The door speakers can just about accommodate a 4.5" component speaker with a little increasing of the mounting-hole diameter. The rear two speakers are of a bigger diameter such that you can easily substitute with a pair of 5.5" component units.


30-10-01, 10:14
Thanks for the info Ash,

How do i open the subwoofer in the rear of the car?
and what is the speaker thats in there? or is it 2 speakers?

If the speaker wires terminate at the amp under the seat,
do i just need to extend the cable up to the head unit?
what connectors would be needed to connect it to the head unit?
standard phono-plugs?


30-10-01, 10:25
I think Dean has the info you need as regards the connections. I'm sure he posted something about 2-weeks back about connecting an aftermarket head-unit to the stock wiring using a readily available adaptor harness.

As for the bass-box I never had to take one apart. I'll have a car here maybe later today, or tomorrow that has one fitted so I'll take a look.


30-10-01, 10:57
Dean and I used the harness that terminates behind the dash, driving the front and rear speakers directly, bypassing the wiring under the passenger seat.

Incidentally, for comparison:

Cubby hole 25.00 (N.I.C.E.)
Toyota to ISO adapter harness 10.99 (Halfords)
Other connectors - not needed (possibly aerial adapter, but this came in the stereo kit).
Time to fit: about 5 hours

Your preout connectors (input FROM head unit TO amp) will be phono plugs at both the head unit and amp ends. The speaker level connectors (output FROM amp TO speakers) will be some other proprietary connector, or flying leads. You *may* have to join these up yourself by soldering or crimping.

Is the subwoofer output from the head unit a line level output like the preouts (in which case you will need a subwoofer amp), or is it a speaker level output?

30-10-01, 14:53

I'm confused now - sorry, i'll try and clarify what i think is
the stock setup :

All 7 speakers go into the AMP,
This then goes into the head-unit.
I need an ISO connector from halfrords to connect to the
leads from the AMP and connect this to my new head unit.
Fine - This should work ok - but if i want to bypass the amp then :

You are saying, that further INTO the dash is a different
connector, that drives the fr/rear speakers directly,
and i should connect the ISO harness to that???????
would that drive the sub-woofer or not?

sorry for my stupidity, but i went to another local installer
(Edworthys) and they quoted me
44quid per hour to fit head unit + ISO connector (10quid)
44quid per hour + 20 quid for new speaker wires to bypass the amp
44quid per hour + 30 quid for a new cubby hole
192 quid for 3 hours work + the cost of the head unit !!

They said that if i simply connnect the head-unit to the amp,
then nothing will work, because Uk head units have built in amps.

now i'm pretty sure thats boll*x! therefore i hate people telling me
boll*x so i am not going there EVER !


30-10-01, 14:59
To be honest, unless you want to do the work yourself and forgo your warranty (possibly), my advice is to buy the head unit from an ICE expert.  They'll install it free at most places, maybe charging a tenner for the harness....

I thoroughly recommend Ipswich Car Radios on Woodbridge Rd, Ipswich (duh).  That's kind of close to Norwich....the guy in there is a perfectionist and he put my alarm and CD player in and it was done absolutely immaculately.

He even knew to turn the ignition off before removing the dash - so has clearly had some Supra experience other than just mine.

30-10-01, 16:48
Sorry, Tony! I'm probably not making things any clearer :-)

First off, Dean and I are both driving the 6 speaker setup directly via the stock harness behind the dash. Fitting the stereo this way was the proverbial piece of p*ss (electronically speaking). One Halfords Toyota-to-ISO connector and away you go (assuming .

HOWEVER, if your stock setup has 7 speakers and an amp then I'm a little bit lost. In fact I have no idea how you would wire up the stock amp to an aftermarket head unit, and whether you should supply it with a line level or speaker level signal, or what. The information about the connectors to the amp I gave was for aftermarket stuff. Whoops.

I recall Paul Booth saying that his car has two wiring setups: one that uses the amp and 7th speaker via the amp, and another which just drives 6 directly.

What we need here is someone who has already fitted an aftermarket head unit to a 7-speaker system, using the stock amp if possible.


16-11-01, 09:31
Well its all done,

Got a new stereo head-unit via work (sony) for about 120 quid
less than retail.

Went back to Compact Car Audio to get it fitted,
the guy i spoke to originally wasnt there - and GOOD - because
the other guy knew EVERYTHING about Supra's installs.


They plugged the head-unit directly into a harness that was
"deep down in the dash" and bypassed the stock amp.
(my guess is that the speakers all go to the front of the dash, then back out again as one harness straight into the stock amp)
This drove all 6 speakers , but did not drive the subwoofer.

My head-unit had a subwoofer pre-out, this could not be driven by the stock amp, so at half-price they installed a tiny-little amp and cable from the head-unit to the amp, amp to subwoofer.

They then fitted a nice little cubby hole to keep my remote control.

All in all an excellent job,  the amp is placed against the back of the
rear passenger side seat, with a little more cable than necessary in order to fold it down when required.

Quality wise, the sounds is FAR superior than stock a much wider range of sound, plus the stock would require 1/2 turn on the vol knob to get decent sound out, then new unit requires setting 2 out of 30 !!!
(speaker upgrades to follow!!!!!!)

They said if you were to ever sell the car, all you would have to do,
was put the stock head unit back in, and wire it back into the stock amp, using all the stock leads which were still there, then remove the new amp, and thats it !

one thing i am not sure about is - they wired a fuse
directly off the battery, and round into the back of the dash
(i assume for the amp in the boot)

Cost :

Head Unit : 189 quid via work
Cubby Hole : 30
1/2 price AMP : 70
Cable : 20
Fitting of all the above (3 hours) : 80
Total charge from Car Audio : 200 quid !

I can upgrade my speakers myself !

Thanks to Mark Kindell for recommending them !

time to get the Kylie tunes on

mmmmmmmmmmmmmmmmmm kylie