Port through rear deck

[SamE30e]

Ok, so I picked up a MTX 12" sub and a MTX Class D mono amp.

I bought a pre built box with it and am putting it in my e30. It's a non ported box, if I wanted to port it through the rear deck, is it just as simple as drilling a hole and putting a piece of PCV tube through a hole in the rear deck?

Any help would be awesome, i'm new to this.

[mbbollman]

I am not reall sure either but I think the sub is actually tuned by the length and size of the tube in a ported box. If you run the tube into the passanger cabin it will probably sound like muddy gargling. Thats just my thought...

Hope it helps

[StereoInstaller1]

Sam, what is the size of the box? In general, ported boxes are nearly twice the size of sealed boxes. Are you looking for a maximum sound kind of thing, or just want a bit more boom? You can poke holes in your car, just don't expect much.

As far as porting directly from the box into the car, don't even think about it if we are talking about the typical 1 cubic foot sealed box...You will make your woofer be dead in short order.

Give me measurements!

Luke

[netcsk]

Yes, the port tuning frequency (the highest output of the port with a steep roll off on each side) is determined by port diameter and length. You need to know speaker specs and enclosure specs to design the port so it doesn't sound horrible.

[SamE30e]

The box is a cube box 1.68cu ft and with a MTX 12" MZS1204 300watt RMS sub and a MTX X300dp 900watt amp. I got a Cap ( I don't really know what the benifit of it is, all I know is that my car starts faster now, i'm new to car audio)

If I put a wrench in the trunk, it will bounce a good half inch off the floor if I turn it up a bit. But in the car its not as loud as I'd like it, I want a nice thump but its more of a constant bass sound.

http://www.mtx.com/caraudio/products...under300XD.cfm Amp

http://www.mtx.com/caraudio/products...erformance.cfm Sub

I need help with the tuning of it, I know how to do the Gain, but not like low pass filter and sub sonic. If someone could help me with that, that'd be awesome. I have a panasonic head unit which is pretty decent and its all running stock componants, minus the tweeters, I couldn't figure out how to run them.

[StereoInstaller1]

I swear...someday I will have the entire world trained to give model numbers....fucking hopeless, I tell ya.

OK, so set your filters like this:

low pass: 80Hz
Subsonic: 25Hz
Bass boost (EQ) : None if possible..or as little as you can stand.
Gain: 90% of max IFthe deck has a subwoofer output, otherwise, tune to taste.

So your box is 1.68 cubic feet on the inside? That is huge, sealed, IMO, but too small for ported. If you were to go somewhere between 1.8 and 2.2 cubic feet ported, you could make very nice clean bass in your E30.

Why are you not using the stock tweeters? They actually sound great if set up properly. Go find an old installer, ask him if he has any spare decent crossovers to sell. DON'T ask a salesman, don't waste your time.

Now that I am actually understanding what you are trying to do, I might be able to get you some decent answers!

Luke

[SamE30e]

Was it bad I gave model numbers? lol

Can't I just wire the tweeters off the 5 1/4's? Or is that a big no no? What would I benefit from by having a smaller box?

P.S what are crossovers, are they that box thing with the bridge?

[StereoInstaller1]

Model numbers let me know exactly what you actually own, since "Panasonic Head Unit" narrows it down to about 300 different decks...it really helps to know what I am dealing with. If I knew the model number, I can suggest deck settings that will clean up the sound drastically.

A larger box will give you lower, cleaner bass...and lets you port directly into the cabin, so your efficiency is maximized. You can gain as much as 12db of output, which can be used either to make more boom, or put less stress on the woofer/amp, to allow it to play cleaner. Clarity is always my first goal, as long as it is fun.

Crossovers are 877777777777777777777777 (sorry, kitten was typing) a device that separate frequencies and send them to the appropriate speaker. The stock premium sound crossovers that are built into the stock midrange are crap, and really limit the sound quality of the front speakers. If you use aftermarket crossovers the sound quality and power handling will improve drastically...you should be able to find a set locally for about $20.

Too much coffee!
Luke

[SamE30e]

Yea, I was looking for the Model number, it doesn't have very many settings. Bass, Treble, Fade, Balance, SW lvl. Thats about it.