Audio upgrades

[Pappa]

Okay I'm thinking of upgrading this:


To a high-quality 6.5" component set.

Then add a decent 12" sub in the back, an amp for the fronts and a monoblock for the sub (in the back i guess).

Anyone else build a stereo in a 300??

Is it hard to fit a 6.5" in the doors? Should i look at alternative placements (build boxes in the dash or similar)?

How much does the alternator deliver, and would it be feasible to upgrade the cable from the alternator to the battery? I guess I'd be pulling a maximum of 400 watts or around 35 amps of load on the battery / alternator. I have a Bosch alternator and a 1.4, car is from 1987. Couldn't find anything on the bosch alternator in the Haynes, perhaps it's been changed in the past.

I took a quick look and it seems like the + cable from alternator to battery is a tiny tiny thing with a quick connector on it, is this correct? It's the only red wire i could find on the alternator. If so this needs correction

Also, which other cables should be "beefed up", how about the cable from B- to chassis (kinda small braided copper cable?), and the cable from engine to chassis (have not checked for it)? Does the alternator have a separate ground wire?

And i guess the car isn't very well dampened, is it hard to fit dampening inside the doors, or does the doors have quite a bit of space in them for dampening stuff?

Thanks,
Jo

[Jason B]

No idea about 300 specific audio stuff (or alternators, being lazy), but if there is anything more general about electrics or acoustics then I may be able to help.

My opinion on any kind of speaker fitting job is that it can be done with a bit of thought, just need to be brave and reach for the drill/knife/fibreglass. My saab wouldn't fit 6.5" speakers on first look, bit of tasteful alteration and they look totally in keeping with the car.

[Pappa]

Alteration isn't much of a problem.. I'll make everything fit.

Anyway, how is this for speaker placement?



6.5" midbass, 4" mid, 1" tweeter

I'll angle the midbass and mid with some fancy MDF rings so they'll point at the driver or passenger, i dunno what would be best. Also the driver's face will be on axis to the tweeter. I'll make a stand in mdf for the tweeter if necessary (the speaker set comes with a tweeter stand designed for this use, will have to see how it holds up).

Would this be okay, or should i change the location of the tweeter to get a higher soundstage. The mid is already quite high up but putting both the mid and the tweeter on the A coloumn would probably lift the soundstage a lot wouldn't it?

[Jason B]

All depends on how tuneable the system will be, what you've suggested looks pretty good and should give you very few problems. Tweeters produce the most directional sound in the most audible frequency bands which is a little conflicting when it comes to placement as you want the directivity focused on the ears, but at the same time if it is not possible to reduce the volume of the tweeters separately (i.e. no active crossovers) then they will have too much prescence mounted on the A pillars. I would say that where you have suggested is a good starting point.

[Pappa]

Really? Thanks! The crossovers included in the speaker set has adjustable tweeter levels, i can choose either 0db, -3db or -6db, so i at least have some sort of adjustment possiblity.

How do you feel about dampening in the doors? I have bought some butyl mats, but not enough to cover two whole doors though. I bought 6 sheets measuring 30x45 centimeters, and counting rough the doors are 50x100cm or so? A pack of 6 sheets was all i could afford Speeding tickets are piling up you know, driving a pure performance veichle pays..

Would it be best to cover the flat areas of the door with the mats and directly behind the speakers with the mats? I also have some rubber foam dampening mats but they're not as stiff, maybe i can use them in corners where i don't need rigidiy?

[Jason B]

I'd be tempted to fit the speakers first and then work out what areas rattle the most before placing damping material. This is mainly because vibration is a very interesting subject and often the best solution is not the one you'd expect.

[Chris_C]

I've got 6x9s in the doors of my future turbo, which sound lame compared to the 6.5" components I have in my rally car/current daily. First thing to note is 6.5" dont fit in the standard location with manual windows, but electrics are easy to fit.

I've got my tweeters on the angle bit where you're drawn 4" on your piccy above, the angle makes the tweeters aim perfectly. The depth is easily cured, mine are mounted on a ring of 18mm ply.

[Pappa]

I've got 6x9s in the doors of my future turbo, which sound lame compared to the 6.5" components I have in my rally car/current daily. First thing to note is 6.5" dont fit in the standard location with manual windows, but electrics are easy to fit.

I've got my tweeters on the angle bit where you're drawn 4" on your piccy above, the angle makes the tweeters aim perfectly. The depth is easily cured, mine are mounted on a ring of 18mm ply.

Hm as you can probably see i have manual windows. Any suggestions where i should fit the 6.5"? I don't mind cutting in the angular part near the original holes and making something out of MDF to slot it in nicely either, but less work would be neat..

[Pappa]

I'd be tempted to fit the speakers first and then work out what areas rattle the most before placing damping material. This is mainly because vibration is a very interesting subject and often the best solution is not the one you'd expect.

That's a good approach, didn't think of that one Sounds good, I'll do that then. Quite a bit more work, but probably better in the end given my limited supply of high quality damping mats.

[Pappa]

Well I've decided to be lazy.

I'm gonna mount the 4" midrange in the factory hole, mount the tweeter where the 4" was gonna be and I've made baffle boards for the 6.5" with an angle bracket on, I'm gonna screw these in between the wheel arch and the door.

This area actually has a hole designed to fit a 5x7" speaker, which seems strange, since it'd be aiming directly at your legs. Anyway there was no sound insulation whatsoever, so i began putting butyl mats and foam mats in there but halfway through i got sick of it, so here's how it came out:




I don't know what you guys call this in england, but it's pretty genious stuff. It'll kill some tyre noise for sure.
It's currently hardening so i have not cut the exess off yet (this stuff expands a lot more than you might think). I'm gonna put some of this in the trunk too i think, but it might be better with a couple foam mats (no butyl mats, too expensive). I'm also gonna put some of this under the hood, the hood does not have any insulation and this stuff will work nicely to kill the engine noise.

Here's how the 6.5" woofers will be mounted when it's done:


Hope it'll sound okay, i understand car midbass drivers are designed to be suspended in an open box, so i guess it'll work out alright.

.. and yes, this looks ghetto. The baffle boards are sourced from a cheap stereo rack I've never used, so i cut these out to make some use of it. (Just to explain the cheesy color and the extra hole)

I also removed the door panel on the drivers side and put butyl mats on the outer door plate and foam mats inside the door panel. The doors in this car has no insulation whatsoever, no wonder it's noisy to ride in. There were two mats of some kind on the outer door plate though, but they're just vibration killers and don't really work that well. Knocking on the driver side door now produces a dead "thud", almost like knocking on a block of concrete. I have not done the passenger side yet, but when i knock it it's ringing like crazy, very bad

I'm gonna take some pics when i soundproof the passenger door tomorrow. It's too dark and cold to work outside now, at least to do anything useful.

[Pappa]

Speakers have been installed on passenger side, sounds very clear, punchy, tight, but i guess the 6.5" isn't mounted optimally.

I'm gonna have to mount it in the door somehow. A tiny baffle board and IB mounting doesn't bring out enough low end, plus the vibrations in this setup probably cause cancellation.

I'm gonna mount it in the rear end of the door, I'll give up some imaging / soundstage, but I'll probably win tons and tons of bass response. It's the only place I'll recon it'll fit without too much work. 3 seconds with a router i guess.



Oh and to fit the 4" mid i had to operate on the door hanger thingie with an angle grinder I fixed it so the door stays open when you open it though, and it closes fine. Just had to shave half an inch off the hook on it.

..this part is broken on the left side though, it's annoying when the door won't stay open



Oh, and the pics are coming! If anyone cares