HitManSE

iTrader: (1)

I know how all that goes
As for needing an SSF at a 30hz tune, nah. You can play down to 24hz w/o any worries. You'll actually reach close to xmax at 24hz but still not there yet. Like I said, there is NO music that plays that low. You'll never hit 24hz unless your playing test tones. And this is in the 3ft box im talking about.

IF you want to add a port to your current box, that would also work. You subs take up just 0.1ft dispacment. It looks like you would need a 3" round port (PVC should work fine) thats about 9-9.5" long. That should place you at about 30hz. I said 9-9.5" because my brain isnt working correctly & I cant figure out how much dispacment the port is going to take up. Thats going to effect to airspace therefor the lenght of the port has to be changed to account for that. That would place you between 30-32hz though. Either way you shouldnt have any problems. Actually it should place you between 30-31hz if you go with 9.5".

Either way with your current box (if you choose to take this route that is) you should still be able to take it down to 22hz (given its smaller) and you'll reach xmax at 22hz. One again, there is no music that low. Even that song by LiL Jon-Get Low hits about 45-55hz. SO either way, you dont really need an ssf.

Hey its worth a shot, worst comes to worst you can just stick the peice you cut your of your back back in, seal it back up and put carpet over it again. Its only going to cost you like $6 got the pipe All you got to lose is $6 and a little time You call man, its not my setup you decide what to do, Im just saying you "could" nearly 2x the output with a few $.

If you want more info, then by all means man go over to CAF and ask away.

slickrick

iTrader: (12)

yeah i go on soundillusions.net. im still just paranoid i wil mess up my subs without a ssf. but if lil john plays at 45hz then if i go no lower than 22 like you said i should be good. what about turn on thumps? i read that and going over bumps can also mess up subs? is this true or shananigans? and also, if its tuned to about 30hz the sub will pound from like 45to 25 like u said? what about the higher bass? i really like the high bass and i dont wanna lose it going ported. moreover, how will i guarantee no port noise? im not exactly the best port builder

HitManSE

iTrader: (1)

As far as it pounding harder, it looks like it should gain 3db starting from 30hz and consistantly gain all the way to 100hz, the gain is still 5db at 80hz and holds through to 100hz (most people cut it off from 63-80hz, but im sure you already knew that ) so its not going to be exacly 2x the output, but more like 1.5-1.8x if you want to be picky about it The 5db gain starts at about 50hz were it matters so it will definetly be an obvious gain.

As for turn on thumps Never heard about that. I used to have that an nothing happend.
Bumps in the road what

As for no port noise im not exactly an expert either so go back over to SI and make a thread about it. See what they got to say. I didnt want to model a port large then 3" because if I go upto 4" you'd have to increase lenght to 17" and im lost after that.

Give them this link...
ftp://208.187.38.55/Phoenix_Gold/ma...rs%20manual.pdf
It has all the info they need to model it perfectly. See what they come up with, besides...id like to see how close I am. Im sure im not too far off be we'll see.

slickrick

iTrader: (12)

yeah the turn on thumps and bumps in road came from an old car audio book my roomate has. i didnt buy it either. im really impressed with the gains i could feasibly get. i cut mine off at 80hz. anything above that i dont need. so where wold i put the ports, on each side of the box? and also, is there a diference in how the bass sounds in a ported compred to sealed? im just wondering this because i havent heard a ported enclosure in a long time. but it seems people who are really into car audio only use ported enclosures.

HitManSE

iTrader: (1)

Yeah, if bumps in the road mess up subs then we'd all have blow subs Thats obviously bullsh!t IMO. Here is the thing about ports though, I dont know how much you know about them but ill try to sum it up.
Here is what the difficult part is about porting your current box and why it would sound the way it would (more on that later)
The more port are you have, obviously you have less chance of port noise. BUT here is the catch, with ports its weird but if you go with a wider port, you'd actually have to use a longer port which is going to take up more space in the box, leaving less room for the subs.

The 1st one I modeled up was with a 2ft box. Add the subs & air space drops to 1.8, add the port & your left with 1.75ft. That was with a 3" diameter port thats 9" long, port tune will be at 31hz.

Now if you want to use say a 4" port, you'd have to make the port 19" long to tune it to 30hz. Now you have just 1.71ft for both subs.

If you want to use two 3" ports... you'd have to use a total of 22.5" or 11.25" for each port to tune it to 30hz, but now your space drops to 1.7ft.
The wider the port, the longer its going to have to be. Its backwards, but hell it works

Here is the wierd thing about how its going to sound, it doesnt have the peaky low end the most ported setups would. The reason for this is because your not playing with a lot of airspace so you'd gain output for sure, but if you had 3ft of air space to play with you'd have a gain of about 7db from 30-45hz compared to the 3db gain its showing right now. So the way its going to sound, is not going to change much. Its just going to be louder. There is no low end peak. So basically all your going to gain just more db output as far as I can tell.

Ill try to upload a pic of the slope of the sealec v.s ported, its looks pretty much identical...just louder.

HitManSE

iTrader: (1)

Here's the pic. I know it sucks, but thats cardomains fault
The ported one is the one on top (green) the sealed is the lower one (yellow)

slickrick

iTrader: (12)

hmm. so it sounds like i could add some polyfill and make up for not porting my box. jk. well i guess there is almost no point to porting my actual box then. mainly because im lazy and id prolly mess up doing it and id be mad if i had to buy a new box. maybe one day, when i start to go deaf and want more bass ill buy a bigger box. i still wonder how they'd sound ported... maybe one day. also, if i stay sealed ill have less rattles.

HitManSE

iTrader: (1)

Heres is another of the cone excursion. Its kinda hard to see, but if you look closley you can see that at 22.10hz is when your close to xmax with the 1.7cu.ft setup using two 3" diameter ports that are 11.25" long each.
Thats at a 30hz port tuning.

HitManSE

iTrader: (1)

Do as you wish, im just showing you what it would sound like

slickrick

iTrader: (12)

so how much les excursion is that? like % wise? and where would i put these ports on the box?

HitManSE

iTrader: (1)

These are the apprx #'s. They are the mm's the cone travels in complete stokes. 36mm is Xmax, with a ported setup the closer you get to the tuning frequency the less the sub travels. So the #'s you see arnt jacked, at 30hz the ported setup would barley be moving. Its once you go below the tuning frequency that the sub starts to swing like mad. Ill even add the 20hz just to show you what would happen should you go that low

Just keep in mind, you'll never find music that goes that low.

As far as were you'd place the ports technically its better to place them firing out the same side the subs are facing, but were talking about the speed of sound here. So you wont notice the diff much if you place the port on the sides of the box, or whatever. Just as long as you have enough room to fit them. It shouldnt really matter much.


............Sealed.....Ported
80hz:.....8mm.......13mm
70hz:.....10mm.....15mm
60hz:.....13mm.....17mm
55hz:.....15mm.....18.2mm
50hz:.....17mm.....18.6mm
45hz:.....20mm.....18.0mm
40hz:.....22mm.....16mm
35hz:.....25mm.....11mm
30hz:.....29mm.....5mm
25hz:.....32mm.....21mm
20hz:.....35mm.....47mm <~~you dont want to go that low
15hz:.....38mm.....64mm <~~

So at 25hz you'll be getting 35% less cone movment.
As 30hz...82% less movment.
At 40hz...27% less movment.
Basically once you go go below 50hz, the ported setup has A LOT less stress on the sub then sealed would. Unless you somehow decide to play a 20hz test tone, then you'll have an inverted cone

slickrick

iTrader: (12)

so at what hz does rap usually play in? 35-55?

HitManSE

iTrader: (1)

35hz is pretty low but it some songs do hit that low. On average it will play in the 45-65hz range.
The song that gets the lowest that I can recall is Late nite tip but 36mafia, it can dip as low as 28hz. It floats in the 30-45hz most of the time though.

superblack98se

You could just take a couple sponges cut it up into pieces and put it under your rear deck! It worked for me!!!

HitManSE

iTrader: (1)

You have no idea how much this thing flexes the rear deck do you?
Id need something way more dense the sponge aka eggcrate foam.

slickrick

iTrader: (12)

yeah mine literally hops around. i put him back there and he was trying to hold it down, it was useless. he said i should use some pillows, i said thankx 4 the pro tip.

vqman

AND YOU SAID MY BOSTON Z6's ARE OVERKILL!!!



-vq

HitManSE

iTrader: (1)

I never said that

HitManSE

iTrader: (1)

This one is for you VQ. Note the ^wall^ & ^nervous^ smilie? Its called sarcasm.

Once again I said THE BOSTON Z6's ARE OVERKILL!!! Im not trying to hide or deny that I said that.

vqman

oh, I get it now..

kinda...

sometimes I don't really get all the smiles.....

cut me some slack, I'm just a dumb jarhead...

-vq

HitManSE

iTrader: (1)

I never went as far as to directly insult you. I did what you asked...twice