PHATMAN5050

Here is the link to the thread in the 5th gen forum. Additions inclue HCCA 15D Sub, HCCA 250R amp to power the sub, completely custom box and enclosure, and surround for the amps. Credit to DND Autosound

hrygeek

Zach, the website is up again. ALL IS GOOD. Go to the pics page on the website. 2001 Maxima

GoldMember

iTrader: (5)

releasedtruth

Incloser? As in "look in closer" or "enclosure" Wonders of public education.... Just playin

MaxSE03

iTrader: (1)

Looks really good. I was thinking about having the sub face that way but thought i would lose quite a bit of sound. How do you like it?

hrygeek

What kind of "sound" are you looking for? Facing forward will produce better SPL numbers and will sound "louder" outside of the vehicle most of the time. Facing into the trunk will give a perceived louder sound because the waves have something to bounce off of (back of trunk).

MaxSE03

iTrader: (1)

Most guys i know get a few extra db with the subs facing the trunk lid(in 4 door cars). Do you have anything to support your claim? I love learning new things.

It's not possible for my box to face forward though. It's 4.4 cubic ft.

hrygeek

What?

#1, SPL measured in decibels is a measure of SOUND PRESSURE. Not loudness. 2 completely seperate things. By firing forward all of the air travel is moving toward the measuring device. ALL air movemenmt is forward. Please do a search on the subject. By firing toward the trunk, waves have a chance to reach your ears giving you a "perceived" loudness.

#2. Why can't you face forward? Zach's box is 4.6 cubes without taking into account bracing and sub structure. Explain please.

MaxSE03

iTrader: (1)

#1 Why is it most guys get a 2-3 bd increase on a mic when facing the rear. Maybe i'm not understanding what your trying to say. Do you have a link? I'll take a look at it if you do. Like i said, i'd love to learn new things. I'm not proclaiming to be an expert!

#2 It is a slot port box and the port would be firing directly into a body panel.

hrygeek

I would have to see that. Hatchback yes. Trunk? Never seen it. Move the port. I'm not trying to get into a pi$$ing match with you but have you actually seen someone gain 2-3dbs (with an spl meter) by facing the subs to the rear? Or is this something you heard. Normally to gain 3db it takes twice the power or twice the speakers. That's a lot of gain for facing a box a different direction (wrong direction at that).

MaxSE03

iTrader: (1)

I'm not trying to get in a pi$$ing match either. That's why i said to show me a link. If that is the case, i would like to see it.

I've heard a 2-3 db gain and i saw a 2 db gain at a SLAP show held in Jacksonville Florida this weekend. The subs were in a Acura Legend. Mic was in passenger windshield both times. Playing the same tone, he got a 143.x on the first attempt and a 145.6 on the second with the box facing the trunk lid. I also know the theory behind a 3 bd gain.

Post this at www.soundillusions.net and see what they say.

Can not move the port! It is to long. I would have to have the sub facing forward and the port facing the rear. Or tear the box apart and make a muti section port.

hrygeek

In a ported box? Which way was the port firing? Need more info than acura legend.

MaxSE03

iTrader: (1)

Do you have a link to something i can read! You keep posting and don't give me any info on the matter.

Not sure if the box was sealed or ported. The announcer said the guy turned his box so the subs faced the rear and was trying to beat his first score. Which he did do.

So is this statement not true:
In the trunk of the car they have room to mature a full waveform, which takes about 6' for a 10" sub. That's why most of the time the subs are put in the back, aimed at the rear of the vehicle.. so the wave will reflect off of the tailgate and come forward allowing more distance for the frequency waveform to complete.

Just give me something i can base your statements on. I'm not calling you out nor saying your full of it. You may have different findings in different cars. I would just like something i can read.

hrygeek

I am still trying to find the mathematics involved in why it's not true. I have info on why it's "louder". I am still on the job. Haven't forgotten and am not backing down, right or wrong. Will stand up either way.

http://www.installer.com/tech/aiming.html

MaxSE03

iTrader: (1)

The first diagram shows the sub box would be at the rear seats with sub facing forward like phatman5050's setup. The second diagram depicts my setup which has rear of box at the seats and subs facing the trunk. The article then says that the subs facing rear setup resulted in much better bass. So now i know i have much better bass that someone with the same setup but facing forward.

There is no reason to get into the 3rd or 4th diagrams because most people do not mount a box at the rear of a trunk with the subs facing forward. Plus we are talking about the setups in the first two.

hrygeek

The article depicts the sound waves and yes facing towards the trunk gives a perceived loudness greater than that of facing forward. I have already conceded this point. The article states nothing about SPL. Again, SPL is SOUND PRESSURE MEASURED in Db's.

MaxSE03

iTrader: (1)

Due to decreased cabin volume, waveform, and cancellation, wouldn't the 1st diagram still have less SPL than the other 3? Maybe not in all cars but wouldn’t that be the case in most?

hrygeek

Cancellation has less to do with spl than sq. When wave match, better sq. Still has nothing to do with SPL.

hrygeek

Cancellation has less to do with spl than sq. When wave match, better sq. Still has nothing to do with SPL.

MaxSE03

iTrader: (1)

After reading through everything twice i see where i was missing the point about spl and didn't realize it until i was driving home from work. Still though, do you have information/links to everything you have said? Also what about the cabin volume? Wouldn't diagram 2, 3, and 4 still produce better SPL in certain vehicles and #1 in others?

Here is a link to a Admin comment on Caraudioknowledge under SPL competion: Link

Here is another link that is pretty interesting: Link

hrygeek

That's talking about true spl enclosures. ones that are made to play at the res freq of a vehicle, burp once, and that's it. Very good article. Still working though.

hrygeek

Okay, here's what I got: If an enclosre is built and tuned to either the res freq or 1/2 the res freq, firing the subs forward (porting forward) will produce higher spl (db's) than firing in any other direction. Boxes that have been built that are not tuned to the res freq (or 1/2) may produce higher spl because the wave then has more room to develop. These and more fun facts can be found at caraudioforum.com, sounddomain.com and you can also email shadetreeaudio@yahoo.com (the guy who published the faq's at orioncaraudio.com). That's all I got.

MaxSE03

iTrader: (1)

Sounds good to me!! I even learned a few things looking through all the links.