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NoLoud4U
08-16-2012, 09:29 PM
I'm trying like hell to get 2 15s to fit in my car. If this will work I'll be reconing the XLs. Net is 7 cubes. Port is 107.5sq with 15sq per cube. 32hz tuning. This is the ONLY way it will fit. My concern is the sub placement in front of the port. This quick drawing is from the top looking down. 26535405

CAT MAN
08-16-2012, 09:31 PM
i did a dd 15 15 box like this and the customer loved it. i have done a few like that none have had many issues at all.

CAT MAN
08-16-2012, 09:32 PM
actually derek here is a vid of the 1515 box 2 DD 1515s - YouTube (http://www.youtube.com/watch?v=v5_-DIKYXtk&list=FLIMJZBUW0QeMA_SHXOTVtFg&index=14&feature=plpp_video)

NoLoud4U
08-16-2012, 09:35 PM
I dont know about moving the subs to the front of the car. It has liked them as far back as possible. That wont work with 15s. Tony he liked it, you know what I'm looking for, will I like it?

CAT MAN
08-16-2012, 09:38 PM
I dont know about moving the subs to the front of the car. It has liked them as far back as possible. That wont work with 15s. Tony he liked it, you know what I'm looking for, will I like it?

in all honesty im confused if this is sarcasm. lol i keed

in all honesty for what you want i dont see any problem just put a port divider in there. and you should be fine. but port forward? its a hatch fire that bish to the rear

NoLoud4U
08-16-2012, 09:39 PM
in all honesty im confused if this is sarcasm. lol i keed

in all honesty for what you want i dont see any problem just put a port divider in there. and you should be fine. but port forward? its a hatch fire that bish to the rear

Its to the rear. I meant the subs.

CAT MAN
08-16-2012, 09:41 PM
Its to the rear. I meant the subs.

gotcha.

you should be alright. if you need i can fool around and design one to those specs just to see.
let me look at it sometime. im sure we could squeeze a tad more space.

NoLoud4U
08-16-2012, 09:45 PM
gotcha.

you should be alright. if you need i can fool around and design one to those specs just to see.
let me look at it sometime. im sure we could squeeze a tad more space.

haha.. There isnt a inch left. That leaves a few inches behind my seat for the amps. Looks like Ill be gutting the hatch again soon, should be fun. It also should be the cheapest way to gain output.

kushy_dreams
08-16-2012, 09:45 PM
Subs look too close to the port, I see them unloading and not getting to use the full airspace. Move them to the back by the port exit.

mazdakid
08-16-2012, 09:46 PM
id try with the subs at the back of the car with the port running along the bottom of the box firing back

CAT MAN
08-16-2012, 09:47 PM
haha.. There isnt a inch left. That leaves a few inches behind my seat for the amps. Looks like Ill be gutting the hatch again soon, should be fun. It also should be the cheapest way to gain output.

i need to gut mine for the new box. i dont like the carpet :p.... you need to come to that show lol just saying

if you want you can try aeros Derek. that gives you some room to play with and aeros in hatches are ***.

or do a bottom port. lotsa things you can try.

CAT MAN
08-16-2012, 09:48 PM
Subs look too close to the port, I see them unloading and not getting to use the full airspace. Move them to the back by the port exit.subs close to a port have been an issue for ever and i've never had a problem. all the airspace will be used regardless


id try with the subs at the back of the car with the port running along the bottom of the box firing back

beat me to it

kushy_dreams
08-16-2012, 09:48 PM
id try with the subs at the back of the car with the port running along the bottom of the box firing back

Good idea, I like the sound of that too, just make sure the port opening doesn't exceed a 9:1 ratio

NoLoud4U
08-16-2012, 09:49 PM
Subs look too close to the port, I see them unloading and not getting to use the full airspace. Move them to the back by the port exit.

Cant. Dont have the width

kushy_dreams
08-16-2012, 09:49 PM
subs close to a port have been an issue for ever and i've never had a problem. all the airspace will be used regardless

I do not agree with this... Moble Enclosurs ;

goingdef
08-16-2012, 09:50 PM
**** man MORE? That ****'s already an experience! I don't know if more would be bearable! i can't even work on mine right now my hearing is about 30% my wife and mom think it's fluid but if it's not better tomorrow I'm going to the E.R.

NoLoud4U
08-16-2012, 09:50 PM
id try with the subs at the back of the car with the port running along the bottom of the box firing back

Cant. Dont have the height

CAT MAN
08-16-2012, 09:51 PM
I do not agree with this... Moble Enclosurs ;
Moble Enclosurs; ?

i learned from him odly enough. alot of things.

NoLoud4U
08-16-2012, 09:51 PM
**** man MORE? That ****'s already an experience! I don't know if more would be bearable! i can't even work on mine right now my hearing is about 30% my wife and mom think it's fluid but if it's not better tomorrow I'm going to the E.R.

Thats ***** man.. I broke my hand yesterday.

CAT MAN
08-16-2012, 09:52 PM
Thats ***** man.. I broke my hand yesterday.
did you break it on the knob of the closet door when you stepped out?








yeah i went there

NoLoud4U
08-16-2012, 09:56 PM
did you break it on the knob of the closet door when you stepped out?








yeah i went there

Funny guy. Go troll JL, end up like me on RF page. I cant even post there anymore.

CAT MAN
08-16-2012, 09:57 PM
Funny guy. Go troll JL, end up like me on RF page. I cant even post there anymore.

how do you handle those kinds of people? i know you like to help. i do too but DAYUM

goingdef
08-16-2012, 10:01 PM
Thats ***** man.. I broke my hand yesterday.

WOW now that ***** hopefully I will be able to hear again in a day or two I hope! right now it sounds like I'm in a room by my self but there are three adults and 6 kids running around and the TV is turned up to 50 but all I hear is muffled talking and the tv lightly in the background along with a ringing:crying: God I want to hear again!

BTW if you need a hand lifting anything hit me up I'm deaf but still able you just got to yell at me to have a conversation.

NoLoud4U
08-16-2012, 10:03 PM
how do you handle those kinds of people? i know you like to help. i do too but DAYUM

A few of them are good people.

---------- Post added at 10:03 PM ---------- Previous post was at 10:02 PM ----------


WOW now that ***** hopefully I will be able to hear again in a day or two I hope! right now it sounds like I'm in a room by my self but there are three adults and 6 kids running around and the TV is turned up to 50 but all I hear is muffled talking and the tv lightly in the background along with a ringing:crying: God I want to hear again!

BTW if you need a hand lifting anything hit me up I'm deaf but still able you just got to yell at me to have a conversation.

I wish I couldnt hear the wife.

CAT MAN
08-16-2012, 10:04 PM
A few of them are good people.

next time ill try to help but that was a lost cause. like shawn saying ported boxes CANT have sq...

---------- Post added at 10:04 PM ---------- Previous post was at 10:03 PM ----------


A few of them are good people.

---------- Post added at 10:03 PM ---------- Previous post was at 10:02 PM ----------



I wish I couldnt hear the wife.
q-tip bro. jab it in

mazdakid
08-16-2012, 10:08 PM
next time ill try to help but that was a lost cause. like shawn saying ported boxes CANT have sq...

---------- Post added at 10:04 PM ---------- Previous post was at 10:03 PM ----------


q-tip bro. jab it in

thats how i went deaf for a few months, got a hole in my eardrum

CAT MAN
08-16-2012, 10:09 PM
thats how i went deaf for a few months, got a hole in my eardrum

i still dont have but 60% hearing in the left ear if i was to guess because of it

NoLoud4U
08-16-2012, 10:12 PM
SQ is subjective, we all know that. I dont think a ported box will ever be on the level of a sealed box for TRUE SQ. You can control peaks but not eliminate them.

NoLoud4U
08-16-2012, 10:17 PM
@Moble Enclosures ; pro-rabbit ;

Inputs before I start tearing stuff apart?

CAT MAN
08-16-2012, 10:32 PM
SQ is subjective, we all know that. I dont think a ported box will ever be on the level of a sealed box for TRUE SQ. You can control peaks but not eliminate them.
6ths 4ths and ported can all be well controlled with the port/s... ;) you know this tho..


and yeah ask them before you go 100% thats just my experience and what i do

NoLoud4U
08-17-2012, 08:48 PM
Bump

pro-rabbit
08-17-2012, 08:51 PM
Cliffs? I missed a lot some how..lol

NoLoud4U
08-17-2012, 09:04 PM
Cliffs? I missed a lot some how..lol

I was hoping you could take a look at my layout. I'm a bit concerned about the port and sub placement. It's a really quick sketch, the 10x25.5 is a slot port going out the back. Box is 13 inches double baffled tall. For my subs reconed to 15s.

Moble Enclosurs
08-18-2012, 11:29 AM
I do not agree with this... Moble Enclosurs ;

Yea, loading can be an issue and if you have ran them like this all the time, as you said, CATMAN "subs close to a port have been an issue for ever and i've never had a problem. all the airspace will be used regardless", then the differences of that an a properly loaded design may not be noticed, or may be overlooked.

It is possible to get a good response from some designs where they are positioned close to the port if the port is acting as a pressure valve or much like an HVAC type air flow setup based on pressure, but the placement of the subs in other design styles becomes more important and sensitive to phase issues and can reduce peaks in a response curve. In fact, it is a great idea to do this in some SPL setups to gain efficiency in the higher bass range to match gain-just have to be careful then of excursion issues. That is the other consideration here.

The thing with ideas such as the one pictured in the beginning of the thread, is that the port will act as a pressure chamber just as much as the compression area does, so placement in that sense is not really a big issue here as long as the port is on the lower side of the recommended cross-sectional area.

You know, here is a way to look at it. THink of the box as a vehicle cabin, and think of a vehicle cabin as a box, because in reality-based on physical aspects of each, they are, and any bounding areas are, essentially the same thing, just each with different dampening and absorption coefficients. The length of a wave does not change, the speed of sound changes minimally based on other minor changes (temp, humidity, etc), but all in all, the propagation is a constant, jsut like it is in a more dense material, such as water (which is where I began my experimentation on sound propagation). In any confined space, regardless of size, reflections occur, and changes are similar to that of any finite space for boundary effects of each frequency. Its the intensity that changes the most. and the pressure fluctuations that change the most.

SO, that being said, think of this design as a blowthrough, that leaks into the trunk still. What will happen is you will get good output (if it is actually designed to do so-and not just based on limitations and tuning), but with phase issues and pressure loss at lower frequencies (not all, but at those that are not excited by the vehicle it will be installed in). The response will have obvious peaks and nulls. And again, this does not say the output will not be good, or it will not have the sound you like........you might even end up enjoying it.......but the subs may not enjoy it as much as you, and neither will the box or the electrical load on the amps. It may have huge load peaks as well, depending on tuning and such, for impedance changes.

All in all, try it. Thats what I am saying. If you dont like it, you will at least know why now. :D. If so, then you were meant to listen to those effects by personal preference. That is something as a designer that is hard to figure for in an acoustical sense, because some are sensitive to a few dB differences, some have different opinions in a good SQ sound (mainly in lower ELF tuning vs higher tuning) and some love the huge BP like peak in some responses and don't care of the mechanical effects that occur as long as the subs last a while, etc. SO, those types of differences are better off measured than calculated alone. This is why you will here other designers say, "real life tuning will override any calculation" and such things as that. Because in reality, they do.
SO, give it a try, if all of the figures show it will work, and report back with some results! It will help others in the long run as well on whether or not they want to do a shot in the dark install for fun and maybe give more confidence for others to blow a few bucks for something that not many others will try.

RangerDangerV2
08-18-2012, 11:31 AM
2.8 cu ft per woofer, sep. chambers, with about 100sq inches of port tuned to about 34. thats what I think you should do.. but no one ever listens to me.

mazdakid
08-18-2012, 12:01 PM
His port is going to take up as much space as each sub gets if he did that ranger, i doubt he has enough room for a box that big.

RangerDangerV2
08-18-2012, 01:04 PM
His port is going to take up as much space as each sub gets if he did that ranger, i doubt he has enough room for a box that big.

then op should not do 15s if he cannot put them in the correct box. if he can find the space for my suggestion I bet it will get down.

CAT MAN
08-18-2012, 04:35 PM
yeah derek just keep the 12s

mazdakid
08-18-2012, 04:42 PM
Maybe keep the 12's or switch to a single 18 if you want to try something different.

NoLoud4U
08-18-2012, 05:11 PM
This is bull ****. How can I gut the entire b piller back and only fit 2 12s. Wtf

CAT MAN
08-18-2012, 06:16 PM
This is bull ****. How can I gut the entire b piller back and only fit 2 12s. Wtf

4 10s? more cone area than 2 12s IIRC. bout 4 net cubes is all they would need

NoLoud4U
08-18-2012, 06:19 PM
4 10s? more cone area than 2 12s IIRC. bout 4 net cubes is all they would need

I cant buy more subs. Reconing was going to be cheap. I think I'm just going to try a new box with a single 6 inch flared areo

CAT MAN
08-18-2012, 06:20 PM
I cant buy more subs. Reconing was going to be cheap. I think I'm just going to try a new box with a single 6 inch flared areo

geet dat port area in or you wont like it.

NoLoud4U
08-18-2012, 06:22 PM
geet dat port area in or you wont like it.

what did you say

CAT MAN
08-18-2012, 06:23 PM
what did you say

been around my homies too long



do lots of port for joo d-man. lots and lots.

Moble Enclosurs
08-18-2012, 06:25 PM
geet dat port area in or you wont like it.

Yep yep. Make sure you have adequate port just as much as volume. In fact the more port and the less compression, the more it will act as a tline lol. But seriously, since your port and driver cone will be in phase in the right frequency range, the port area is just as important as cone area as it acts the same......round ports more so than slots, but still the same effect. In other words, port area can equal cone area and it will act more efficiently than a smaller port because the port works like the cone for pressure. So, either smaller subs and a lot of port (better idea nearly always) or biggest subs possible and the likeliness to go better sealed wall or take the gamble of a smaller port and chance a bad setup.......thats the honest truth.

NoLoud4U
08-18-2012, 06:26 PM
been around my homies too long



do lots of port for joo d-man. lots and lots.

1 6er will be 9sq per cube. I can go 34hz and up.

pro-rabbit
08-18-2012, 06:37 PM
I was hoping you could take a look at my layout. I'm a bit concerned about the port and sub placement. It's a really quick sketch, the 10x25.5 is a slot port going out the back. Box is 13 inches double baffled tall. For my subs reconed to 15s.

Hit me up with the specs when you get around to it.. gross and net volumes and such...

Sorry been crazy busy out here so keeping up with various threads gets a bit hard some times.

Also, what are your goals? SPL goals can offer a vast difference from daily and you can get away with many different things that are typically issues in daily setups.