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Dee-vub wrote: Bloody hell thats mental! Now i have you and top's brains to pick when it comes to my install!!

When it comes to making a box, how do you get the best potential out it?

I have a 15" RE sub, but i dont just want a box plonked in the middle, i want it all to flow as a nice install but want to get the best sound out of the sub! How do you go about 'tuning' it?

you want your sub to be used to its full use
go for a bass horn setup
not ported or sealed or bandpass stuff
i started with my 15" explode in a sealed box
then a larger sealed box
then a larger ported box to sonys instruvtions
got louder bit by bit
untill i made a bass horn setup
the bass hurts didnt think 1 15" could make so much crisp deep and stupidly loud noise going all throught the hz range unlike a sealed or ported were you either get top end from a sealed or low from a ported

look up bass horn pictures on the net usually used for large PA systems

let me know if want some more help on this

Sounds drool worthy mate!!!! I dont even know what a bass horn setup is
I'll have a wee looky

Dee-vub wrote: Sounds drool worthy mate!!!! I dont even know what a bass horn setup is
I'll have a wee looky

yes its worth looking up and the time it takes to make it
it a real pain in the ass lol
as i didnt want to use all the boot with 1 sub
ony half i made the box to use all the room on the on side so it sloped with the seats
which made loads of angles and maths for the 6 boards inside the box
but i like it so much i want to used the hole boot with 3 horns together
set at different hz with 3 12" woofers
just saving up for the new amps and subs
cuz im savin up for the cupra shell swap as well lol


heres a crapy little sketch the blob thing on the left is the sub
and the diagnal lines are the partitions were the air (the red) moves
getts push around from the left to right and then up the side and out the top
to a hole above the sub were there the air goes in and out
as you can see its a long root round and out for the air
so you get the resistance of a sealed box
but as its ported you get the depth
so its the best of both

ive just tried to get some pics on the net bit couldnt find the one i bassed mine on but if u want to know just ask i will draw a sketch


this is how it looked when i got it in there will take some more pics for u gys[/list]

BratManGTi wrote:you want your sub to be used to its full use
go for a bass horn setup
not ported or sealed or bandpass stuff
i started with my 15" explode in a sealed box
then a larger sealed box
then a larger ported box to sonys instruvtions
got louder bit by bit
untill i made a bass horn setup
the bass hurts didnt think 1 15" could make so much crisp deep and stupidly loud noise going all throught the hz range unlike a sealed or ported were you either get top end from a sealed or low from a ported

look up bass horn pictures on the net usually used for large PA systems

let me know if want some more help on this

a well designed ported box will play all frequencys in a vehicle far better than a horn design, to be honest most manufacturers sub box designs leave a lot to be desired and the ported sub boxes use ports which are way too small for them to be of any use, i would suspect that the sony design used a tube type port of 3 or 4" in diameter in probably 2 or 2.5 cubic ft, way too small a port to be functional!

a horn is designed to work in vast areas ie, like you say nightclubs or concert sized venues, unless you have an estate car that is passat length (ie not a polo) or a van with the enclosure at the rear of the vehicle then a ported enclosure (well designed) will play lots better than a horn of any sort as there simply isn't enough room for the full wave to develop in a smaller car like a polo

i am sure your happy with your xplod sony item, but as far as hifi goes they are not too well built and do not sound anywhere near as good as a JBL GT4 or GT5 of a similar size, however as long as you are happy then thats what matters, however unless you have heard a very good sub to compare the sony too you will not (no offence) know the difference between a good sub and an average one, it is all in the enclosure and design but for average joe, i would not even consider a horn type enclosure as the results from a good, well designed ported enclosure will far outway the results of a horn

BratManGTi wrote:

Dee-vub wrote: Sounds drool worthy mate!!!! I dont even know what a bass horn setup is
I'll have a wee looky

yes its worth looking up and the time it takes to make it
it a real pain in the ass lol
as i didnt want to use all the boot with 1 sub
ony half i made the box to use all the room on the on side so it sloped with the seats
which made loads of angles and maths for the 6 boards inside the box
but i like it so much i want to used the hole boot with 3 horns together
set at different hz with 3 12" woofers
just saving up for the new amps and subs
cuz im savin up for the cupra shell swap as well lol


heres a crapy little sketch the blob thing on the left is the sub
and the diagnal lines are the partitions were the air (the red) moves
getts push around from the left to right and then up the side and out the top
to a hole above the sub were there the air goes in and out
as you can see its a long root round and out for the air
so you get the resistance of a sealed box
but as its ported you get the depth
so its the best of both

ive just tried to get some pics on the net bit couldnt find the one i bassed mine on but if u want to know just ask i will draw a sketch


this is how it looked when i got it in there will take some more pics for u gys[/list]

having typed all the above (must press refresh next time before replying!) the enclosure you have is not a horn, and definately not what most clubs/concerts use! its a transmission line enclosure, i would agree that these do sound really quite good, and are as near to free air as you can get = natural sound quality!

as far as three different tunings is concerned, this will compromise sound as unloading and phase cancellation will occur, if this covers all the different frequencys well then it should be well designed and as such, you would need to add two more with identical tuning, ideally with a common chamber and the line area at the throat and the ported end times'd by three for maximum effect and sound quality

the phase of the pressure waves leaving the end of a transmission line enclosure will vary with line length ie the distance from rear of driver to the open end of the tunnel, if you were to tune three differently and put them in a car then the phasing at the end of the three ports would effectively cancel the front waves of the drivers in the other two transmion lines and generally arse about with the sound

if you do want three seperate enclosures for ease of removal to use some boot, then i would build three identical enclosures that fit side by side in the boot and then they will all sum together and make one very loud quality sound as long as you have the room for the three with the same dimensions as they are now

F*ck me thats all soooo dam confusing! I have no clue what you 2 are yammering on about

Anyways, i am going to go with a sealed enclosure.....situated in the middle of the boot with an amp either side. It'll be subtley shaped and be smooth inside the boot.

The gear i have gone for is

Pioneer DEH9800BT
Rainbow C-265 2 way componants
Focal 2.75 2 channel amp (power the comps)
RE SE15" Sub
Diamond audio D7401 monoblock class D amp(power the sub)

What you guys reckon to that gear? And will a sealed enclosure suffice??

cheers guys

all sounds pretty good to me!!

I'm not a massive fan of 15" subs tho, small and punchy for me

all depends on how its setup up though, so let us know how it goes down!

Yeh i got a really good deal on the 15" so, went for it! Thats why i am going to go for the sealed box to help regain some of the punchiness

a well designed ported box will play all frequencys in a vehicle far better than a horn design, to be honest most manufacturers sub box designs leave a lot to be desired and the ported sub boxes use ports which are way too small for them to be of any use, i would suspect that the sony design used a tube type port of 3 or 4" in diameter in probably 2 or 2.5 cubic ft, way too small a port to be functional!

right then to start off
the 2.5 cubic ft and 3 or 4 inch port are not even half what sony recomends in the manual
these arnt your adverage 15" explod peices of crap off the shelf with a 300w rms
these are phase 2 c class explotion subs with 780w rms and peak of 2500w
i have the one in "horn" designed box
was 38db louder than my freinds twin 15" c classes in a double ported box
at the midlands sound off championships
i have had a JBL sub it was a GTi5000 which was special order
the top of the reange sub in jbls 06 range
it was a great sub but a pain in the back side to power and would not reach the higer hz like the sony
also the same for the latest JL bad boy but not as bad
my next subs will b 3 of the the new jls in 3 different boxes
this will ensure the whole hz range is covered to its best with a nice natural sound as the depth of the ported cannot match the depth of bass from a horn
as prooven in the sound offs

BratManGTi wrote:right then to start off
the 2.5 cubic ft and 3 or 4 inch port are not even half what sony recomends in the manual
these arnt your adverage 15" explod peices of crap off the shelf with a 300w rms
these are phase 2 c class explotion subs with 780w rms and peak of 2500w
i have the one in "horn" designed box
was 38db louder than my freinds twin 15" c classes in a double ported box
at the midlands sound off championships
i have had a JBL sub it was a GTi5000 which was special order
the top of the reange sub in jbls 06 range
it was a great sub but a pain in the back side to power and would not reach the higer hz like the sony
also the same for the latest JL bad boy but not as bad
my next subs will b 3 of the the new jls in 3 different boxes
this will ensure the whole hz range is covered to its best with a nice natural sound as the depth of the ported cannot match the depth of bass from a horn
as prooven in the sound offs

so what was the box spec as i am curious to know for these subs as i can't find them on sonys website (even in the old models)??? a link would be good

what db score did your box hit then? and what did your mates hit? not heard of the midlands sound off championships tho, got a link to that too?

dumdum wrote: so what was the box spec as i am curious to know for these subs as i can't find them on sonys website (even in the old models)??? a link would be good

what db score did your box hit then? and what did your mates hit? not heard of the midlands sound off championships tho, got a link to that too?

ditto

every 3dB is double the pressure, so 3dB more is 2 times, 9dB 8 times, 15dB 32 times, 24dB 256 times....

so you're talking roughly 2 to the power of 12 times more powerful when you say 38dB! did you mean 3.8?

38dB equates to ~4000 times more pressure than your mate with 2x15" subs.

what did he have?! paper cups?

As above really, Dave is exactly right. It's said that a gain of 3db is twice the volume!

My ported box is tuned to about 45hz which is quite high really so it doesn't really play anything under 30hv very well if at all. It plays the higher frequency's fine, in fact a lot of the ported designs I've heard have done - even one tuned to 29hz! I'm sure you can back that up dumdum (Am's Altezza)

As dumdum asked, what did your install hit db wise just out of interest and do you know what mic was used?