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Discussion Starter #1
In Car Entertainment.
I would like to start a serious thread on the subjest to help me.
Please post pics, suggestions and tips on what you have done to your 33.

I'm after SQL not SPL



My setup so far which I started in 2004 lol and still haven’t got round to finishing it.

Head unit
Alpine CDE-9827R

Amp
DLS CA21

Sub
JL Audio 10w3v2-d4 @2 ohm

I have just found out that the amp I bought with the sub should not be used at 2 ohm. I took it apart and found a blown mosfet and resistor. I have fixed that now and plan to use it for the front components and add the following.

Components
SPL Dynamics SD5.2 5 ¼” Thinking of going to 6.5" later

Sub amp
JL Audio 500/1

Sub box
I have just had a slot ported box made by a friend, wow what a difference that made. I gave him moral support when making it and held this and that.

I can now use the JL sub amp without worrying as it will go down to 1.5 ohms

I connected the components today and ran them off the head unit.
I need to figure out how to fit them properly and not look too out of place, HELP!

I was planning on using an MDF ring to screw the component to and then shaping the other side to fit to the metal of the door in the lower front corner. When I looked today, guess which of the two types of regulators I have. Yes, the ones that point to the front and are right in the way!!

I noticed that all the OEM Alfa speakers have all fallen apart, the rubber / foam connecting the cone to the frame has disintegrated!

I was thinking of putting down some 20mm ply wood in the boot floor, screwing the amps down to this and then screw some 1” by 1” strips to the ply wood base and then cutting out the shape of the amps and sub from ply board to make a false floor to hide the wires. I could also make a bracket to hold the sub box in place with a padlock for security.
To be able to get to the space saver I could undo the padlock, lift out the sub box, remove the false floor, which wont be fixed and open a hinged opening for the spare.

Any other ideas?


Would leaving a circular hole over the spare wheel well cause a problem with the sub being on top of it, rather than a hinged opening?

Anyone got any ideas on upgrading the tweeters but still keeping them in the same place as OEM ones?
 

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I haven't worked on a 33, but I will apply general principles. :)

For the speakers, you want to use the door cavity as the 'enclosure' for the 5.25" woofers. Can you post pics of the door trims (front and back), and of the metal door?

With my 155, I will have to customise the fitment, as there are no factory door speakers. So I will cut a round hole in the metal 'plate' to accommodate the back of the speaker. To facilitate the 'sealed enclosure', I will use self-adhesive sound deadening sheets (ie: Dynamat Xtreme) to deaden the doors and cover over the service holes, stopping air leaks. So I'll cut a round hole in the metal in this pic, nearby the wiring loom/plug: http://pic20.picturetrail.com/VOL97/467659/20674651/337040745.jpg

A hole will be cut in the door trim in a suitable position where it's flat. There will be a gap between the metal door plate and the back of the door trim. An mdf wood spacer will be screwed into position.

On the surface/front of the door trim, I will secure another mdf spacer. It's shape and trim will be cosmetic, so probably trimmed in black vinyl. The speaker (Sinfoni S165W) will screw to this outer spacer. So basically:
speaker > outer spacer > door trim > inner spacer > metal door

So the speaker/spacer will end up over the light grey trim, infront of the grab handle: http://pic20.picturetrail.com/VOL97/467659/20674651/337040907.jpg

I don't know what the 'regulators' are. I presume they can be relocated, even if you have to extend the wiring?

I am fitting 3-way components, so the midrange will go into the kickpanel areas in fibreglass pods. The drivers will be angled upwards/inwards, with extensive testing to find the best imaging.

I will probably fit the tweeters in the factory speaker locations, atop the dash. But you need to experiment here too. Usually, having them 'all the way out infront' and 'out to the sides' is best. That's because it keeps the pathlengths relatively similar. The pathlength is the distance the sound has to travel from the tweeter to your ears. For best imaging, the L and R PLs are the same, but this is somewhat impossible in a car when the seats are not dead centre in the middle of the car! You sit to the R or L; in the driver's seat, the PL from the R tweeter is less than the L; this affects imaging and the soundstage. But having the tweeters 'out in front' as far as you can place them, minimises the difference. So, at the base of the A-pillars in the corner with the windscreen can be ideal.

But this brings about other compromises. In particular the reflection of treble off the windscreen. Hence, experiment. It will be a compromise between 'best imaging' and 'practical fitment'.

A false floor in the boot is the way to go. Totally up to you on how it's designed: where each component fits, and where they are functional/accessible, and position/direction of the subbox.

In the 155, I have built a part-fibreglass box to fit on the lefthand side. False floor is from 6mm mdf, supported by mdf blocks underneath, bonded to the chassis. Amplifiers will be close to the rear seat. Hinged section to access the spare underneath.

http://pic20.picturetrail.com/VOL97/467659/20911958/381625108.jpg
http://pic20.picturetrail.com/VOL97/467659/20911958/381691796.jpg
http://pic20.picturetrail.com/VOL97/467659/20911958/381842433.jpg
http://pic20.picturetrail.com/VOL97/467659/20911958/385230549.jpg

'Padlock' seems a bit extreme ;) . Having a hole in the false floor sounds fine. Just ensure the subbox is securely fitted.

:)
 

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Discussion Starter #3 (Edited)
Thank you for your comments, I have been reading up on this stuff and think i am not going to be able to keep an OEM look and will have to make something.
Here are some pics.
With trim
What someone else has done
Without trim
Close up of regulator 1
Close up of regulator 2

NS boot
middle boot 1
middle boot 2
OS boot
boot carpet / template

sub placement

sub dimensions W584mm x H305mm x D327mm
sub amp dimensions L340mm W235mm H60mm

Speaker amp dimensions 51,5mm x 280mm x 290mm

I had the idea to use mdf spacers on the metal of the door, with the face that is attached to the metal shaped so it is air tight, i was also thinking of dynamatting the whole of the metal in one sheet and cut out screw holes for the door handles, then i found out how expensive it is lol.

Rough dimensions of the boot floor looking in from the rear ourside of the car is
94 cm wide
76 cm from front to back boot catch panel
62 cm spare wheel well
90 mm high to the sill behind the rear seats
 

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The photos are very helpful. :)

Sealing over all the service holes in the door is important for good speaker performance. Dynamat Xtreme is certainly relatively expensive, but there are cheaper alternatives on the market. Speak to your local ICE specialist retailer to see what they use.

For a good air seal, you can also use closed-cell foam rubber stripping as a gasket between your spacer and the metal door, and other joins.

From the pics, if you're prepared to cut a slither of metal from the doors, you should be able to fit (round) 6.5" speakers into the area where the factory speaker is.

Your boot is a bit smaller than the 155. You just have to design the layout so that everything fits. You could also mount the amplifiers onto the subbox; they tolerate this fine.

:)
 

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Discussion Starter #5 (Edited)
It has been suggested to use wickes high tack flashing tape, Hi-Tack Flashing Strip - Alumimiun Flashing - Roofing -Building Materials - Wickes
Thanks for the tip on sealing the door and what to use.
I am prepared to cut away :) I will be getting replacement door cards on Tuesday and will modify them, that way I can keep mine original if I ever sell the car.
The problem with fitting speakers in the original position is that they get covered by the passenger and my legs,


at the bottom front would be ideal, or above my knee here

or making a kick panel box,


I couldn’t find any info on what volume would be good for 6.5" mid woofers. I was thinking the sound stage would be better with the speakers facing front to back, compared to side to side but don't know if the lack of space in the kick panel box compared to the space in the door would justify making them. I could cut the carpet away and leave the back of the kick panel box open, so that sound goes into the space behind it, what do you think? I've attached some pics of the foot well for you to see the size, with my 5 1/4" woofer in shot for size reference.




What about dash mounting?


This is what the dash looks like underneath, I think the air feed for the door windows might get in the way but may be moved but then how does one cut out the holes without removing the windscreen?



I have heard that it’s not good to mount the amps on the box due to vibrations to the pcb. I am happy to mount the amps on the floor, may even light up around them :)

I tried to make a quick sketch using Google sketch up but couldn't figure out how to make shapes with exact measurements, doh!

I went to make a start on the boot floor today but B & Q didn't have any sheets big enough, with a friend, the chippy “master craftsman” as he likes to be called :)
I will put some 5mm blocks around the bottom, so that no wires get pinched. I have 90mm to play with so was thinking 15mm plyboard + 5mm blocks, 65mm x 65mm edging and 5mm plyboard to top it off.
The 65mm x 65mm will be used around the edges of the amps and the 5mm ply will have cut outs where the amps and sub is, I can also drill holes into the 65 x 65 for the wires to go straight into the amps and therefore hide all wiring under the top ply sheet.
If there is room I would like to make cut outs for my oil, petrol can, fire extinguisher, first aid box and engine coolant containers. I wish I knew how to use Google sketchup or had access to a cad program.

I will put wires in place for rear speakers because i will eventually like to put a 5.1 surround system in in the future with a dvd head unit but knowing me that will be in another 6 years, not sure where to mount the center speaker though :) I could just get away with analogue surround now though
 

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Again, photos have been very helpful. :)

It has been suggested to use wickes high tack flashing tape
Ah yes. I have used this in the past as a cheaper alternative. For the purposes of sealing over the holes, it should work ok.

I have found the main limitations can be:
*thinner and more flexi than 'proper' incar sound deadener; the stiffer the better, cos it will not flex, and will help create a more rigid 'enclosure' for the speaker
*narrow rolls: I haven't seen it in sheets, and only in rolls, up to 4" wide; just makes it more tedious to apply
*not as dense/heavy: not that important for the purposes of sealing holes; but the other purpose of sound deadener is to add mass to the panels, to reduce the (audible) resonant frequency; means less audible vibrations/rattles; deadener also converts kinetic energy (vibrations) into thermal energy (heat) as part of the 'stopping vibrations' function

But definitely a reasonable alternative if it does work out cheaper. But could be worth roughly calculating how much it costs for a roll or two, compared with 3 'sheets' of Dynamat Xtreme or alternative incar deadener.

The problem with fitting speakers in the original position is that they get covered by the passenger and my legs,

or making a kick panel box,

I couldn’t find any info on what volume would be good for 6.5" mid woofers. I was thinking the sound stage would be better with the speakers facing front to back, compared to side to side but don't know if the lack of space in the kick panel box compared to the space in the door would justify making them. I could cut the carpet away and leave the back of the kick panel box open, so that sound goes into the space behind it, what do you think?

What about dash mounting?
There are pros and cons to each.

From a sound quality/performance point of view, you should aim to:
*have at least 10L/0.3cuft for a sealed enclosure for the 5.25" woofer
*aim upwards and angled 'inwards' towards the opposite-seat headrest

A door cavity might be around 1cuft/28L of volume, which is fine for a car audio speaker. Speakers are generally designed to be mounted in the door, taking into account the size of the average car door.

If the 'enclosure' is very small, you won't have much midbass. In a door, a 5.25" speaker should be able to play down to 100~150Hz without probs. In something like a 3L/0.1cuft enclosure, it may struggle to play down to 200Hz loudly; the small box overdampens cone movement.

The concept of a 'sealed enclosure' is quite important. In the kickpanel, it can be difficult to build a largish enclosure; but also ensure it's somewhat sealed. You don't want the soundwaves off the front of the cone interacting with the soundwaves off the rear; interaction can lead to cancellation/phase issues, which manifests as loss of some frequencies like loss of bass or some of the midrange/treble (it'll just sound relatively poor).

So it ends up being a compromise. The ideal position might well be in the kickpanel areas, angled appropriately. But build suitable enclosures will be a challenge. As such, the doors remain the most convenient place to install, at some loss of imaging. I think the Alfa 75 set is even worse, yeah?!

I wouldn't mount them on the dash without doing a lot of work. It looks a bit flimsy. You'd really need to reinforce it and build enclosures underneath. That might be do-able, but it's again another inconvenient approach.

I have heard that it’s not good to mount the amps on the box due to vibrations to the pcb. I am happy to mount the amps on the floor, may even light up around them :)
An amp of good build quality (good soldering) will not fail. They are subject to constant vibration from being inside the car anyway. 'Heat' remains the biggest cause for amplifier failure, but most amps are well designed these days.

But if you can floor mount them, no probs.

The design of an installation is half the fun :) . As you're doing, it's good to consider all options and trial-fit things here and there, then decide on what the best compromise is.

If you're going all-out, I'd build kickpanel enclosures for the 5.25" drivers. You can make a complex shape (with mdf wood and fibreglass combo) that houses the speaker in the kicks, and extend the enclosure onto the floor as a low, flat 'box'. You will lose some floor 'height', but this area can be the most convenient to build into.

:)
 

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Discussion Starter #7 (Edited)
Hi,
Based on the volume needed and the box size, I will mount in the door.
What about using the closed-cell foam rubber stripping and thin MDF cut out with routed edges to fill the larger holes and then flash tape the whole surface, or is this overkill? Does it matter if there is an obstruction between the rear of the speaker cone and the door cavity? I assume as long as it’s a good seal it shouldn’t matter?
How much and where should i put flash tape on the outer inner doorskin, i assume i need to?

I just ordered some MDF spacer rings, 1x 5 1/4 by 9mm and 1x 6 ½ by 9mm and 1 x 6 1/2 by 18mm for when I upgrade. I will mount the 6.5s to the inner door and the 5.25 to the outer and when I upgrade to 6.5s I will replace the outer ones with 6.5, that way it will save me doing the same job twice.

I think this will open up a can of worms but here goes lol
I am soldering the spade connections to my speaker wires for 3 reasons.
1, bare wires will corrode after time.
2 crimping is only done well with an expensive tool, which I don’t have access to.
3 I want to be able to upgrade, so soldering directly to the speakers is inconvenient. The can of worms debate is vibration in a car on soldered joints, am I going about this correctly.

I was so gutted that I couldn’t make a start yesterday, next week end I guess.
Thanks for your time and explaining
 

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Discussion Starter #8
SC16v you said
To begin with , there are two versions of power window mechs for the 33. One of them has the motor looking down towards the lower front corner of the door, and the other one has the motor facing in the exact opposite direction.
Both of them fit all 33's ( S3's ) but you will need the second one so you can have the clearance in the front lower corner of the door.
in this thread
http://www.alfaowner.com/Forum/alfa-33-sud-and-sprint/210147-my-33-xtreme-tuning-2.html
do you have any pics of them?
 

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if you're brave enough to go for it Al, i reckon the dash mounted woofers would be mega! You can make a sealed enclosure in there, and just get some longer plastic pipe to re route the air feed round it.

I've always gone for sealed boxes when making speakers, even if they are thin and weedy, cos a small part of schoolboy physics that i remember said something bout a speaker that makes 1db noise in free air will make ten in a sealed enclosure... You also get the benefit of the elastic rebound effect of the air trapped in the enclosre. A rule of thumb says sealed boxes are harder to drive, but its also harder to hurt units that are in a sealed box. most car speakers a 4ohm with high sensitivity. so are very easy to drive. The biggest losses in audio quality in a car are from resonant frequencies (things that rattle in the doors etc), and the ability of cars to soak up most of your low frequencies.

Have you considered mounting the amps to the backs of the rear seats? Not sure how heavily you intend to abuse the amps, but air flow is a consideration as they can get mighty hot when hammered.

If you wanna go 3-way with your speakers, i would highly recommend getting some active xovers. Think maplin do budget ones, and there's usually a selection on the ebay... will help keep the speakers in phase, and can help to tune out resonant frequencies. more scope for tuning to your taste too

Joe
 

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Discussion Starter #10 (Edited)
I can get 45.7x81.2cm dynamat for £12.21 +P&P £2.50
Or
150mm 10m Wickes high tack flashing tape for 11.99
Is it necessary to do the whole door like this?
http://i212.photobucket.com/albums/cc290/spresv/alfa/IMG_0098.jpg
Spresv, what siize sheet did you use?

Alfasloot
I have never taken out a dash in my life, I’m scared of squeaking and rattling once it goes back in, I don’t think there will be enough room to make a 10L enclosure either. That pic of the dash is from Pats car that he broke, I could ask him if I could take another look or swap with mine after I modify that.

RE; the amps, I would like to be able to use the fold down seats, with the boot being filled, when the sub is out at some point, so I will stick with flat mounting them. I won’t be abusing the amps as I want to be able to hear in my old age :) and will eventually upgrade the components for SQ, however I could always leave some holes in the 65mm wood surroundings and put some thermally activated fans there with some ducting from the spare wheel well’s drain plug.
I have an active crossover but again I have been told it’s a PITA to set up. I looked at hiring a spectrum analyser but had no luck finding anywhere. My local car audio place says that they can setup in about 1 hour at £50 an hour, so I might try passive and then active but it means running another run of wires lol. I don't think it's worth it with cheap £80 components, maybe when i upgrade
 

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What about using the closed-cell foam rubber stripping and thin MDF cut out with routed edges to fill the larger holes and then flash tape the whole surface, or is this overkill? Does it matter if there is an obstruction between the rear of the speaker cone and the door cavity? I assume as long as it’s a good seal it shouldn’t matter?
How much and where should i put flash tape on the outer inner doorskin, i assume i need to?
At a minimum, use the tape to seal over the holes. mdf panels can help make the 'covering' more rigid, and is a technique I use too (3mm mdf cut to shape, with a coat of paint to make them water resistant).

If you tape right over the mdf to hold it in position, there isn't a need for any gasket (foam rubber).

This is the work I did on my GT:
http://pic20.picturetrail.com/VOL97/467659/19095446/313625219.jpg
http://pic20.picturetrail.com/VOL97/467659/19095446/313625228.jpg
http://pic20.picturetrail.com/VOL97/467659/19095446/314773594.jpg
http://pic20.picturetrail.com/VOL97/467659/19095446/314773601.jpg

The back of the speaker should 'communicate' with the door cavity. It's not essential for the back of the speaker to line up with the hole. So some overlap with the metal of the door would be ok. I presume that's what you're asking.

On the outer door skin, focus on the area immediately behind the speaker. Ideally, cover the inner and outer skins completely, but for best bang-for-buck, seal the inner skin, and do behind the speaker on the outer skin.

I am soldering the spade connections to my speaker wires for 3 reasons
I am an advocate of soldering. There's good and bad quality crimping and soldering. Just do a good job of whichever method you choose.

If you wanna go 3-way with your speakers, i would highly recommend getting some active xovers.
An 'active' 3-way setup would require 6 channels of amplification for the speakers: 1 channel per driver. Not sure he's prepared to add another amp and active xover unit for this purpose.

I can get 45.7x81.2cm dynamat for £12.21 +P&P £2.50
Or
150mm 10m Wickes high tack flashing tape for 11.99
Is it necessary to do the whole door like this?
You will probably need at least 2~3 sheets of Dynamat (Xtreme) of that size, to do both doors to the 'minimum' discussed above.

I have an active crossover but again I have been told it’s a PITA to set up.

I don't think it's worth it with cheap £80 components, maybe when i upgrade
Exactly. I only recommend people to go 'active' when:
*they have enough knowledge/experience to tune such a setup
*they are mixing and matching different brands/series of drivers, where there isn't an off-the-shelf passive xover available
*the component speakers have a passive xover unit designed to suit bi-/tri-amping: usually always much more expensive speakers
*they wish to have time correction on individual drivers/channels

:)
 

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Discussion Starter #12 (Edited)
Well my MDF rings didn’t arrive today so will be here tomorrow, the guy I was supposed to pick up the door cards from blew me out and couldn’t spare 5 mins for me to collect, he was “ILL” Maybe he will drop them off to me later this week to make up for it, otherwise I’ll have to wait another week!!

OK I will make some templates of card and get my chippy friend to cut them out of 3mm mdf with a routed edge, I’ll glue them in with the foam rubber, incase they rattle loose :) Then at a later date I’ll dynamat the whole door and behind the speaker when I get my door cards.
Do dynamat not do large sheets anymore like the pic of a 33 with the whole door done? I popped into a car audio shop and the sheets they had would only do ½ the door and they only had 1 box, doh!

You were correct about what I was asking regarding the back of the speaker :)
Looks like I maybe buying a Dremel tomorrow :) and I’m still waiting for my 4awg splitter for my amps

Thanks again for your suggestions and help.
 

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Dynamat sheets come in slightly different sizes. But none are big enough to be applied as one piece to a whole door (it would also be a tricky job doing it in one piece).

This is Oz pricing, but it details the sizes of sheets according to what pack you buy: http://www.fastfoursforumscarclub.com/temp/fhrxstudios/pdfs/dynamat_pricelist.pdf

Note, the pic you showed of the 33 door uses older Dynamat. They used to have 2 qualities of product: the older stuff (like pictured), and Dynamat Xtreme which is better. Now there's only Xtreme AFAIK.

:)
 

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Discussion Starter #14
I see.
These are the two best prices, i now assume the cheaper is the older type
Dynamat Dyn10125 Car-vision.co.uk
and the more expensive is the extreme type
Dynamat 10425 Soundproof Mat - Extreme £18.38 including VAT. DYN10425. Buy discounted car audio online at In-Car Express

I have calculated to do the whole door requires about 4250cm2 one sheet of 50cm by 76cm and another at 9cm by 50cm

I went to buy some plywood yesterday only to find they dont cut to size and the sheet was too big to fit in my car

Rather Pi..ed off, i chased my MDF ring order only to find they had my phone number wrong and my bank card number wrong, i gave them my email address for a conformation sale when i placed the order, i can only assume they wrote that down wrong as well as no one emailed me, incompetance really annoys me, another day wasted!!

Looks like the only thing i can do is make card templates for the MDF
 

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The older stuff is no longer listed on the Dynamat website. There may be old stock around, but check first.

If you want something cheaper than Xtreme, then check with local retailers what brands they offer, cos there's many different options.

I hate incompetence! ;)

:)
 

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Discussion Starter #16 (Edited)
:) Thanks again.
Well everything is on hold, waiting for 4awg distribution block, well one in 2 out, it has still not been ordered and might be there for saturday. Finally got a conformation email for the MDF rings at 16:00, even though i called at 11:00 am, so they won't be with me for another day!!
Did get a quote for the plywood, 12mm or 15mm, what do you think?
I just ordered some second skin damplifier along with replacement tweeters, as i am missing one.
 

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Plywood is ok, but a little harder to work with (saw, sand, etc).

For 'covers' over the service holes in the doors, 3~6mm is ample.

:)
 

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:lol: That makes better sense!
 

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Discussion Starter #20 (Edited)
lol
so... 12, 15mm or something else??
Got my MDF rings, not completely round.
I just phoned the guy to arrange to pick up the door cards tomorrow, only to be told he hasn't got them FFS! Loosing interest now! so i am going to have to cut mine up.
I can't decide if i should dash mount the tweeters, door mount, or a piller mount them and should i replace the doorbell wire with the same stuff I'm using? Ithink the woofer and tweeter should be asl close as possible to eliminate sound delay but a better soundstage if inline with the ear.
 
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