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View Full Version : where should i put my subs???



88 Accord DX
01-23-2003, 09:49 AM
ive got my subs in the trunk right now but they hit so hard they rattle it and im too lazy to rattle proof it....

so what should i do? put them in the back seat or leave them in the trunk.

im scared to put them in the back seat because i dont have an alarm system yet and im afraid of someone stealing them. also they might be a little too loud right behind my ear. but in the trunk they sound gay on the outside of the car and i hate that.

AccordEpicenter
01-23-2003, 12:46 PM
if you put em in the back seat they will probably get stolen and anyways they would prolly sound like crap too. If you wanna get some sound deadening for cheap, get some spray foam and foam the shit out of your trunk lid. I still havent found out how to completely soundproof the back deck area, but you might wanna work on your 3rd brakelight, they can make alot of noise against the glass

n1accord88
01-23-2003, 02:31 PM
And anyway, it doesn't matter what it sounds like outside the car, it is you that is listening to it inside the car....if you have a balanced sound inside that is all that mattered.

I don't know if you have tried yet, but you could always put mounting brackets on your box and mount them to the trunk, it would take a lot to take them then.....and you could face the woofers towards the seat.

88 Accord DX
01-24-2003, 05:51 AM
okay i sat down and i found where the sound is coming from. one is the liscense plate which is an easy fix. next is the cross bars on the trunk lid and third is the sides of the trunk. i went to go buy some spray foam but they said it was $30 a can so i said fuck you and have a nice day.ill prolly go to walmart and get some cheap houseing foam and use it.

dXsquared
01-30-2003, 04:21 PM
it should be 4 bucks a can for expanding foam


Travis

Mike's89AccordLX
01-31-2003, 11:51 PM
I thought everyone put them in the trunk.

TJ89Accord
02-01-2003, 12:04 AM
it would probably sound worse on the back seat. And it would definatly look worse / ghetto on the back seat.

tim

AccordEpicenter
02-01-2003, 10:26 PM
most competitors put their subs in the back seat or closer (ie, wall) but unless you have them completely isolated, i mean COMPLETELY isolated from the trunk there is no point, they will sound like ass unless they are mounted firing directly up, because the inverse sound wave coming from the back of the speaker will reflect off the trunk lid and cancel out a fair portion of the original sound wave from the front of the speaker. To illustrate it, put your subs in your back seat firing forwards (or in your trunk better yet) and listen to them with the trunk closed, and then compare em with the trunk lid open, youll be shocked at the difference.

n88accordLX-i
02-03-2003, 12:18 AM
Dude, no competitors put their subs in their backseat... The reason a wall works so well is because its totally sealed off from the rest of the car, so the subs are pressurizing the front seat area, not the entire car, just keep the subs in the trunk and face em towards the backseat.

87DXHatch
02-03-2003, 12:40 AM
Shit, I haven't replied to this yet? I must be losing it...

It's called slot loading theory, boys. It mainly applies to ONLY sealed boxes (some of it applies to ported too, but it gets complicated as hell with that).

The theory is this:
When a sub plays a beat, there are two waves: 1 wave that goes straight out from the sub, the way you would think it would. However, there is a SECOND wave that goes BACKWARDS from the sub. If you have the sub in the trunk facing forward with the box close to the cabin, the back wave will reflect off your trunk and come back almost opposite of the originial wave, causing SEVERE cancellation and a SEVERE reduction in sound. If you have your sub like this, try listening to it with the trunk closed, then open the trunk. If it gets louder when you open the trunk, move where you have your box IMMIDIATELY.

So, going by slot loading theory, the BEST place to put your subs in your trunk is as far back as they will go facing backwards. Positioned like this, the primary wave will almost immidiately hit the trunk when it fires, almost immidiately reflecting backwards. It will be almost 100% in phase with the secondary wave, then, thus increasing the overall loudness of the sub.

Welcome to my world, boys, prepare to get lost in it ;)

Vanilla Sky
02-03-2003, 01:13 AM
could you eliminate the secondary wave with anything? just curious

88 Accord DX
02-03-2003, 05:53 AM
okay i have the subs in my trunk facing towards the trunk lid. if i lined the boxes with foam or that pink panther stuff would it help to reduce the secondary wave.

Square
02-03-2003, 11:03 AM
If you have some extra money, get some Dynamat sound deadener and line the inside of the trunk with that. They also make it for liscense plates. It's a little bit of work but you will be quite impressed with the results. :)

87DXHatch
02-03-2003, 12:26 PM
I don't think you guys really get it...

As long as the primary and secondary waves are nearly in phase, the secondary wave ADDS it's power to the primary wave. It's only when they are out of phase that it SUBTRACTS from the primary wave. If you eliminated the secondary wave (something that I'm pretty sure is impossible) then it would be half as loud as before.

Here's an example of slot loading theory: Downfiring home subwoofers. The sub is a couple inches off the floor, facing downwards, and firing so that the primary and secondary waves nearly line up.

Any other Q's? :wave:

n88accordLX-i
02-03-2003, 06:08 PM
Originally posted by 87DXHatch


So, going by slot loading theory, the BEST place to put your subs in your trunk is as far back as they will go facing backwards. Positioned like this, the primary wave will almost immidiately hit the trunk when it fires, almost immidiately reflecting backwards. It will be almost 100% in phase with the secondary wave, then, thus increasing the overall loudness of the sub.



:werd:

88 Accord DX
02-03-2003, 07:50 PM
Originally posted by 87DXHatch
I don't think you guys really get it...

As long as the primary and secondary waves are nearly in phase, the secondary wave ADDS it's power to the primary wave. It's only when they are out of phase that it SUBTRACTS from the primary wave. If you eliminated the secondary wave (something that I'm pretty sure is impossible) then it would be half as loud as before.

Here's an example of slot loading theory: Downfiring home subwoofers. The sub is a couple inches off the floor, facing downwards, and firing so that the primary and secondary waves nearly line up.

Any other Q's? :wave:


yeah so what your saying is to get both waves to move at the same time and speed. what if i made a box with the speakers facing toward or away from each other. like this----->
[ (>o o<)]
get it?

man forget it ill just leave them as they are.

87DXHatch
02-03-2003, 08:34 PM
Then you'd get some mondo cancellation unless you wired one speaker out of phase (ie: + to - and - to +)

Square
02-03-2003, 09:21 PM
This is not true. There is no such thing as "slot load theory" or cancellation from the backwave of the sub. True, this will happen if the speaker is playing free-air, (out of the box), but not in the box, or any box for that matter. And having the subs facing the rear of the car, straight up, or into the back of the rear seat will make a minimal difference, (only 1 to 2 dB in output).

The whole reason for having a speaker in a box, depending on what kind it is, is to keep the backwave from interfering with the frontwave.

Sealed enclosures trap the backwave in the box and uses it like a spring to better control the movement of the woofer.

A ported encloser uses a "tube" or "slot" to tune the backwave to a point to where is exits the box at the same time as the frontwave, adding to the overall output at any given frequency.

A bandpass enclosure utilizes both of these concepts to get "the best of both worlds", meaning that it will produce the tight, accurate bass of a sealed enclosure with the extra power output of a ported enclosure with the added feature of being able to tune it where the frequency rolloff of the sealed eclosure starts to drop off.

Hope this helps clears things up a bit. :D

88 Accord DX
02-04-2003, 05:49 AM
Square sounds and looks (his sig) like he knows what hes talking about.

87DXHatch
02-04-2003, 09:54 AM
Originally posted by Square
This is not true. There is no such thing as "slot load theory" or cancellation from the backwave of the sub. True, this will happen if the speaker is playing free-air, (out of the box), but not in the box, or any box for that matter. And having the subs facing the rear of the car, straight up, or into the back of the rear seat will make a minimal difference, (only 1 to 2 dB in output).

The whole reason for having a speaker in a box, depending on what kind it is, is to keep the backwave from interfering with the frontwave.

Sealed enclosures trap the backwave in the box and uses it like a spring to better control the movement of the woofer.

A ported encloser uses a "tube" or "slot" to tune the backwave to a point to where is exits the box at the same time as the frontwave, adding to the overall output at any given frequency.

A bandpass enclosure utilizes both of these concepts to get "the best of both worlds", meaning that it will produce the tight, accurate bass of a sealed enclosure with the extra power output of a ported enclosure with the added feature of being able to tune it where the frequency rolloff of the sealed eclosure starts to drop off.

Hope this helps clears things up a bit. :D

You are the type of person I hate. A person that is not only ignorant on a subject, but then refuses to think that there is another possible answer to the question.

Ok, genius, when did I mention ONCE the back wave?? I NEVER did. I said SECONDARY wave. NOT back wave.

The backwave is what you build an enclosure for. The SECONDARY wave is a product of the speaker moving forward.

The SECONDARY wave is what causes cancellation, in a SEALED enclosure. In free air, the forward and backward waves cancel each other out.


there is no such thing as "slot load theory"

Well damn, then me and all these guys are just idiots then...

http://installer.com/tech/aiming.html
http://www.caraudioforum.com/vbb2/showthread.php?s=&threadid=116559&perpage=15&highlight=slot%20loading&pagenumber=1

Um, only 1 to 2 db? Actually, slot loading can boost it up to 3 db, and 3 db is a DOUBLING in loudness. Want to know another way to boost your db by 3? Add a second sub. Hmm... slot load and get 3 db that way... or add another sub and get 3 db that way.... HMMMMMMMMMMMMMMM.

And your comment on bandpass is totally wrong. Bandpass is NOT the "best of both worlds." Bandpass is just that: a narrow BAND of frequencies boosted, and the rest attenuated. Bandpass enclosures are like ported enclosures, only they are cut off at a certain point. Meaning: bandpass enclosures are retarded to make for anything but competition, where a narrow band of frequencies needs boosting.

Hey, you know what? Prove me wrong on any of these, with some evidence, and I'll gladly admit I was wrong. I'm all about learning. And I'm trying to lay some education on you, let's hope you take it. ;)

Square
02-04-2003, 11:06 AM
Alright.

For one thing, I have been installing show quality systems for sound quality and SPL comps before you ever reached 1st grade!!!! I've also been installing home theater systems that cost well over $200,000 for years now. So don't even try to come in here and tell me that I'm wrong!!!!!

Second, do you really think I'm going to listen to a LITTLE ZIT FACED PUNK like you who thinks he knows what he's talking about?! You think you get a little information from a site and know everything there is to know about audio!

Third, try reading this page which is part of that link you posted. http://installer.com/tech/freqandwave.html

It tells you right there in black and white!!!!!! A 3 foot distance from the sub to the back of the trunk is not going to make one hell of a difference in sound when the wavelengths are 22 feet long and longer the lower the frequency!!!!! Dumb ass.

And slot loading has to do with a type of subwoofer enclosure, NOT if the trunk lid is open or closed. If that's the case, why don't we all just take the damn trunk lids off of all our cars?! Slots are just another type of port!

And yes, I know the effects of adding ports, or another driver will double the output.

I AM NOT totally wrong about bandpass boxes either. Yes, they have a narrower range because they act like a natural crossover. However, what do I know? I'm only 33 freakin years old!!!!!!!

I feel sorry for everyone on this board that actually listens to you. It's called "The Blind Leading The Blind" and you are without a doubt the ignorant one here.

Try going to school and becoming certified in this field before you ever try to go up against me again! If you can reach my certs, MECP and a degree in Electrical & Acoustical Engineering, and prove me wrong, go for it! I will probably be retired by then, but oh well.

Have a super duper day!

:flip:

87DXHatch
02-04-2003, 11:35 AM
:D Thank you I will.

Well damn then, if you had made your original post THAT clear, I wouldn't have responded as I did. (BTW, I absolutely LOVE getting people pissed ;) :D :flipa: )


It tells you right there in black and white!!!!!! A 3 foot distance from the sub to the back of the trunk is not going to make one hell of a difference in sound when the wavelengths are 22 feet long and longer the lower the frequency!!!!! Dumb **:eek:**

I know it says that, but I don't entirely agree. I can stick my head next to a sub playing 20 hz and hear it perfectly. A 20 hz wave is 55 feet long. Does this mean I have to hear the entire wave to have my brain register that it is a 20hz note? I don't think so...


And slot loading has to do with a type of subwoofer enclosure, NOT if the trunk lid is open or closed. If that's the case, why don't we all just take the damn trunk lids off of all our cars?! Slots are just another type of port!

I used slot loading in reference to where he puts his subs. Slot loading is the theory that is used when you face subs towards the rear instead of towards the front, not a whole new enclosure design, even though I know you can design slot loaded enclosures. Why would you take the trunk lid of the car? :confused:

I jumped on your case about bandpass 'cause I was pissed that you flat out said that slot loading theory does not exist when it does.


I feel sorry for everyone on this board that actually listens to you. It's called "The Blind Leading The Blind" and you are without a doubt the ignorant one here.
Name some stuff I've been wrong about. :flipa:


Try going to school and becoming certified in this field before you ever try to go up against me again! If you can reach my certs, MECP and a degree in Electrical & Acoustical Engineering, and prove me wrong, go for it! I will probably be retired by then, but oh well.

When I got to this part, I crapped myself. That is EXACTLY what degree am planning on going to school for :eek:!! Now I want to learn as much from you as I possibly can! (See, I'm all about the learnin' ;))

I checked your age (as you obviously did mine) after I posted and I noticed you were 33. It just made me wonder...

Enjoy your dinner! :D

87DXHatch
02-04-2003, 01:48 PM
I'd bet you've read my other threads... am I wrong anywhere? I'd really like to know because I thought I was right on all of them... let me know if I'm otherwise ;)

importracerkid
02-09-2003, 04:13 PM
Square
I like your setup in your accord, did you do it your self, how would I go about about doing something like that?

TJ89Accord
02-09-2003, 04:42 PM
I know that in my car, I had my box facing the back of the car, as close to the back seat as possible. I moved to towards the back about half a foot, and I can hear a VERY big difference. I think it had something to do with the port being pretty much blocked off before, that and it was a very tight squeeze where it was, maybe not letting the sound get through to the inside of the car.

tim

loco87
02-10-2003, 10:04 PM
Second, do you really think I'm going to listen to a LITTLE ZIT FACED PUNK like you who thinks he knows what he's talking about?! You think you get a little information from a site and know everything there is to know about audio!

ouch...zing!!

87DXHatch
02-10-2003, 11:12 PM
Originally posted by loco87
Second, do you really think I'm going to listen to a LITTLE ZIT FACED PUNK like you who thinks he knows what he's talking about?! You think you get a little information from a site and know everything there is to know about audio!

ouch...zing!!
:lol lol, you just made my week.

http://www.caraudioforum.com/vbb2/images/thumbup.gif

Vanilla Sky
02-10-2003, 11:31 PM
actually, i was throwing around some of the theories 87DX is talking about here, and yes, they do work... i got a 5dB increase (mostly by luck, i guess) simply by ptting my sub as close to the wall as possible (this is measured by a radioshack meter, so i don't know if it's accurate or not... it's probably not, though)... it's enough of a difference that i have to re-adjust my parametric EQ on my computer so i can hear the mid and treble, too... too bad it's coming from a crappy soundcard...

AccordEpicenter
02-12-2003, 10:32 PM
well i dont know about you but everybody else in the world gets the most gain by pushing the box in their trunk all the way back until it hits the seat firing towards the trunk lid. It reduces the cancellation due to phase shift.

meanaccord
04-18-2003, 11:20 AM
ok, since you guys are talking about boxes. What do you think about slot ported boxes. I have a sealed in mine pushing 1.65 to each chamber with some audiobahn's, right now its just the tight bass, not deep. Everybody tellsme that slot ported boxes knock soooo much harder. Should i try that or just increase the area inside my box to about 2 if not larger?

POS carb
04-18-2003, 07:39 PM
how big are those audiobahns?

meanaccord
04-19-2003, 10:55 AM
they are 12's, they need 1.25 -1.65 internal volume, i want that strong deep bass without distrotion. So everybody....slot or 2 c.u. ft sealed?????