Basic advice to fit aftermarket speakers

[Mattyc]

Hello. Going to fit some pioneer component speakers I have lying around to my Alfa Gt. Just a few quick questions. These speakers have a crossover. The wire which clips to the stock woofer via a yellow clip, can I just cut off the clip and use them wires to connect to the crossover then connect crossover to each individual speaker OR, does this wire already have the stock crossover, high pass fuse thing attached? Hope that makes sense! Trying to work out which wire to run the crossover off. I know not to use the tweeter wire. Also, any advice on which colour wire to use for negative and positive would be excellent. Thanks for looking and any help in advance.

[shiny_car]

Yes, just cut off the yellow plug. The audio signal is 'full range', no crossover beforehand. The (non-BOSE) factory woofers have no crossovers, and receive a fullrange signal; the tweeters have a tiny inline capacitor that functions has a highpass crossover. The capacitor is mounted within the tweeter.

Can't remember if there's markings on the plug or factory woofer to help determine polarity. Is there a '1' and '2' on the plug? It is important to work it out; if the polarity is wrong on one side/door, the speakers end up out of phase, which will sound worse.

If you have a multimeter, you can do a continuity check between the terminal/wire in the yellow plug, and with the terminal connecting to the headunit (which can be identified by the wiring schematic on the factory headunit; eg: the schematic will show what terminal is for the front left positive wire).

[Mattyc]

Thanks shiny_car, you seem to be the ICE king!
I have bought some adapters which just connect to the stock yellow plugs, these i think can only be fitted one way and the leads are coloured black and red so HOPEFULLY should be easy to get the polarity correct.

[Mattyc]

Just say, for arguments sake, i got the polarity the wrong way, is it really obvious?
Is there a industry standard to wire something.
E.G. in my kenwood head unit, it says the wires going into the harness:-
Purple, rear right (+)
Purple black, rear right (-)
Gray front right (+)
Gray black, front right (-) etc etc.
From this i take it kenwood have solid colour as positive and stripe/mix colour as negative.
Is this industry standard and do alfa conform to this standard or do alfa just wire it up randomly like everything else??!!??!!
Hope that made sense!

[shiny_car]

If the speakers are out of phase, it's fairly obvious, though sometimes only when compared with being inphase. The imaging can be poorly focused (eg: the vocals are diffuse rather than pinpoint accurate), and bass can suffer.

The difference can be subtle, the point that it sounds good either way. Even if speakers are wired (electrically) inphase, they can be acoustically moderately out of phase and sound a little off. Basically, if it sounds good, it's likely inphase.

Wiring harnesses do follow an industry standard. So your Kenwood wiring harness will have those standardised colours and stripes. However, the Alfa wiring - and virtually all other marques - does not follow this standard.

This is my factory GT headunit schematic sticker: http://pic20.picturetrail.com/VOL97/.../291012684.jpg

It will be the same as your original one (if you don't still have it). So, for example, you can find the terminal in the Alfa plug for the RF+ (right front positive) speakerwire. Set a multimeter to continuity mode, and probe that terminal, and one of the wires in the right door speaker plug. When the wires correspond, the multimeter will beep, and thus you've confirmed the (right front) positive wire. The other will be the negative wire, and can be confirmed by probing it together with the RF- terminal.

No digital multimeter? A basic one with continuity mode should only cost 15 quid, so go get one! Handy for all autoelectrical work (incl checking voltages, etc).

[Mattyc]

One last stupid question, if BOTH speakers were connected the wrong way and both were out of phase, would I notice? In my door, the yellow clip had a 1 and 2 on it. 1 was pink and black and the 2 was purple and black. I connected the 1 lead, pink and black, to the positive on the crossover. As long as I connect the 1 to the positive on the other side will that be OK? The door panel was easy to take off BUT a nightmare to put back on. I have done the best I can but its not as good as previously, bit loose and unlevel but the best I could do. May have another go tomorrow.

[shiny_car]

'1' should be the 'positive', no probs.

Indeed, if both are wired (electrically) out of phase, they will be (acoustically) inphase. Except with the rear speakers. But probably not a big deal.

[Mattyc]

Thanks shiny car, your a star!

[Mattyc]

All fitted and sounds fantastic! Thanks for your help! Not doing the rears, just leave them on really low.

[a17esh]

A up guys, I have the bose system in my GT and want to add some components.

I have a pioneer head unit fitted.

I need some brackets made up for the GT, any pics of what I need to make and a idiots guide....or can I just buy them.

I will def sound proof the door cards.

Not fitting the speakers is it just cut the clips and attached to the speakers?...or will the bose be a pain in the arse?

[a17esh]

I know fitting amp amp would be easy........should I just do that and leave the bose plugs taped up?

[shiny_car]

Here's a couple pics of what you'll find behind the door trims: BOSE speakers in the GT doors:
http://pic20.picturetrail.com/VOL97/.../312714695.jpg
http://pic20.picturetrail.com/VOL97/.../312714694.jpg

Remove the coaxial speaker, the plastic speaker ring/baffle, and the foam lining, you end up with a door that has lots of 'service holes' which are terrible for sound quality ('X' marks the holes):
http://pic20.picturetrail.com/VOL97/.../312967214.jpg

The best bang-for-buck method of sealing the holes is using quality car audio self-adhesive sound deadener (eg: Dynamat Xtreme, Stiner Road Kill, etc) and cover over the holes. I went to more extremes, and covered the outer door skin (ie: inside the door), then cut mdf panels for each service hole (painted, to make them moisture-resistant), then applied Dynamat over the top:
http://pic20.picturetrail.com/VOL97/.../313625228.jpg
http://pic20.picturetrail.com/VOL97/.../314773594.jpg
http://pic20.picturetrail.com/VOL97/.../314773601.jpg

To make new speaker baffles/rings, I used mdf wood. To ensure the front of the speaker frame gently sealed against the back of the speaker grill, I measured the total depth from the door to the front of the BOSE speaker; it was 40+mm (I think it was 41mm). I then determined I needed a 35mm thick ring to recreate this (with my 6mm thick new speaker frame); so I made a new spacer from 18+3+18mm mdf.
http://pic20.picturetrail.com/VOL97/.../314773618.jpg
http://pic20.picturetrail.com/VOL97/.../314773597.jpg
http://pic20.picturetrail.com/VOL97/.../314773615.jpg
http://pic20.picturetrail.com/VOL97/.../314773613.jpg
http://pic20.picturetrail.com/VOL97/.../318943430.jpg
http://pic20.picturetrail.com/VOL97/.../319876520.jpg

I used a router to create 'perfect circles' but that's because I have a router and circle-cutting jig. You don't have to be so precise, and can simply use a jigsaw to hand-cut the rings. No-one will see them behind the door trims!

You can see that the shape of the piece that screws to the door has 'feet' for the screws; use the BOSE spacer as template to trace around the edge for this same shape. Then mark the holes for the screws through the BOSE spacer too. My 3 pieces are glued (PVA glue) together, with screws to help hold them together; painted, to make them moisture-resistant.

You can just cut off the BOSE yellow plugs. MAKE CAREFUL NOTE of the polarity of the wires. In my second photo above, the 'larger spade plug' wire connecting to the BOSE tweeter with be the POSitive speakerwire. Trace that back to see what colour wire in the speaker loom it corresponds with. If you accidentally stuff up the polarity to one of your speakers, it will be out of phase, and performance will likely suffer. If your new speakers have spade terminals, I suggest crimping on new terminals to the speakerwire to suit, but if you are experienced with soldering, you can solder directly onto the speaker terminals (avoiding sending too much heat through the terminal/tinsel wires and voicecoil).

Fitting an aftermarket amp may be easy. Of course, you'll need to run a new fused powerwire from the battery, through the firewall, under the door sill trims/carpet, to where the amp is (presumably in the boot). Time consuming, but easy enough to do if you are experienced with such work. Plus the groundwire, remote wire, RCA cables, speakerwire.

[a17esh]

Wooosers.........

Well I actually have the wires all ready for the amp....apart from amp to front speakers...... just need to get them through the door.....so may as well amp them up :-).... help from your thread actually.

These speakers brackets look like a fiddle to make, I will however give it my best shot.

Just sound dead at the back of the bracket to get a seal around it?

What about autoleads adaptors....are they any good? for 9.99 would save me a lot of messing....but they look like they will leave gaps all over.

[a17esh]

OOO and what size speakers?

[shiny_car]

Originally Posted by a17esh

Just sound dead at the back of the bracket to get a seal around it?

Stick pieces of deadener over the holes. You can do smaller pieces if using it sparingly, or larger pieces to cover not only the holes, but deaden the whole panel (to reduce resonance/vibrations). So the deadener serves those two purposes here: creating a sealed enclosure for the speakers, and reducing resonance.

What about autoleads adaptors....are they any good? for 9.99 would save me a lot of messing....but they look like they will leave gaps all over.

Haven't seen or used them. Unless they are bespoke for the GT (or 147), they may not be a perfect fit. Custom spacers can be made to be a perfect size for the doors and speakers.

Originally Posted by a17esh

OOO and what size speakers?

6.5".

[a17esh]

Thank Shiny..........

There are the adaptors i was on about.

[a17esh]

Car Audio Equipment | Buy online at Car Audio Security oops these are them sir!

[shiny_car]

What are they made of? Wood is better, because it's more dense/solid. But plastic will do.