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Kenny Pollock
12-18-2006, 10:17 AM
Doing the wall with two 18" fully-loaded BTLs.

My wall is 16.94 ft^3 gross right now... I still need to take sub displacement out and figure port tuning and displacement.

I'm doing subs side by side, port on top. I have about 9" of height to play with and 34" width.

This wall is for daily/Bass Race. I'm wanting to hit mid 150s, but I appreciate my lows. My last box was 10 cubes (yeah, I know, too big) tuned to 30hz and I loved it.

We're looking for some dimensions... how long should the port be and what size height/width of the port.

16.94 ft^3 gross is what we're working with before displacement. I'm figuring .7 for both subs.

I talked to TypeRBass and he helped us out a little, just looking for some assurance and answers.

KARLEON
12-18-2006, 10:35 AM
Kenny, just a question....How many "WALL" threads do u have?

Have u tried some of those online calculators? Just type in your information and it automatically calculate everything for u? Or was you wanting someone to go through with a pen and pad and figure it out for u just incase those calculators may be a little bit off?

KARLEON
12-18-2006, 10:37 AM
BTW, i have used those calculators a few times, and doubled check with pen and paper, and they do seem to come out accurate. Just a thought for u.

Kenny Pollock
12-18-2006, 10:39 AM
How many wall threads?

This will be my fourth thread relating to the wall... and I'm currently building my 3rd wall. This one will be perfect :)

Thanks for the information, I've never designed an enclosure, so I'll check out one of the scripts online.

Kenny Pollock
12-18-2006, 10:57 AM
Talked to Nick RE: this... learned some things.

We're gonna do 5.3" high and 34" wide... port length 31"... should bring us to ~32hz after sub and port displacement hopefully.

j3bus2k3
12-18-2006, 10:59 AM
I'll crunch the numbers real quick...

oxsign
12-18-2006, 11:01 AM
What are you putting this into?

KARLEON
12-18-2006, 11:02 AM
wow, congrats on the walls. i didnt know u actually completed the other walls. I was just noticing different threads by you and it was referring to a wall.

Good luck on this one

j3bus2k3
12-18-2006, 11:03 AM
I got 29.39Hz...

Kenny Pollock
12-18-2006, 11:04 AM
Thanks :)

Vic: It's going in my 1996 Chrysler LHS.

Wall so far:
http://kennypollock.com/newnewwall.jpg

Kenny Pollock
12-18-2006, 11:04 AM
I got 29.39Hz...
Good enough, if it's not hitting mid 150s on the TL we can just cut the port length a little to raise tuning, right?

Mr Bojangles
12-18-2006, 11:09 AM
looking good.. I'm about to redo my wall with 2 solo-baric 15" and 12cuft. Good luck man

Mr Bojangles
12-18-2006, 11:10 AM
Good enough, if it's not hitting mid 150s on the TL we can just cut the port length a little to raise tuning, right?

yep!

j3bus2k3
12-18-2006, 11:10 AM
Did it again, taking into consideration the port walls on each side adding 1.5" to the width and height and came out with 30.7hz...

Kenny Pollock
12-18-2006, 11:20 AM
Thanks Scott :) Teaser pic of the wall up soon :up2somet:

dbornotdb
12-18-2006, 11:28 AM
Teaser pics in other thread.
:D

CBFryman2
12-18-2006, 11:33 AM
180sqin of port area for a wall with 2 18's. I'm no expert on building walls but I'd do at least 250. It isnt like you are tight on space. I'd also do plugs but that is just an idea. Easy swap in swap out. 30Hz for daily listening, 35Hz for bassrace, 45Hz for SM 1-2 or SS 1-2.

CBFryman2
12-18-2006, 11:33 AM
PS
The wall is looking great this time. :naughty:

j3bus2k3
12-18-2006, 11:38 AM
I'm just glad you got ahold of PE before they shipped out your speakers, lol. Pics? :D

CBFryman2
12-18-2006, 11:41 AM
Just ran some numbers. 9"x34" with a 1" space top and bottom and a 2" space on each side for the bolts will allow for 210sqin of port area.

If yo uhave a TL on hand Build a port as deep as it will allow and run a sweep from 20-80Hz. Shorten the port in 2" incraments untill you get the flattest responce on the TL. That will be your daily plug (who cares about tuning?).

Next find a song you want to bassrace with. and crunch the numbers to tune for it, start a little low and shorten untill you get the best average score you can muster. Keep shortening untill you start to loose on the song. Build another plug as long as the port was when you did your loudest run.

Next find your peak frequincy with your daily port and if it is above the peak of your bassrace song use your bassrace test port and shorten it untill you get your best peak. That will be your dB Drag port (dB Drag is always fun and you know you will want to spend the extra $10 to compeat in it in 1x and 2x competitions).

That is what I would do personally. Just a suggestion. :)

saywhat?
12-18-2006, 11:42 AM
kenny, make sure that port doesnt take up a massive amount of displacement....it should be fine, but i would go close to 200. meade has about the same I do believe, and his does just fine (and moves a **** ton of air I might add)

systembumping
12-18-2006, 11:50 AM
It's for daily? Where are you gonna fit the girls?

ngsm13
12-18-2006, 11:50 AM
12-13cubes NET

TUNE IT HIGHER!!!!!!!! It'll still sound good... tuning that low is stupid for this type of system.

Tune it 33-36hz... you have two 18's... they can handle the lows.

Port, 180-240 sq. in.

nG

CBFryman2
12-18-2006, 12:27 PM
It's for daily? Where are you gonna fit the girls?

There is a passeneger seat. I know from experence three girls and myself can fit in my truck...Comfert isnt an issue as long as they are hot. :laugh:

The hottest always rides in the middle. Stick Shift FTW.

xluben
12-18-2006, 12:37 PM
i'd go for a switchable (meade-style) port.

then if you're not happy, you can just make a new port, not have to start hacking up the wall.

CBFryman2
12-18-2006, 12:41 PM
i'd go for a switchable (meade-style) port.

then if you're not happy, you can just make a new port, not have to start hacking up the wall.

What he (I) said. :naughty:

saywhat?
12-18-2006, 01:14 PM
i'd go for a switchable (meade-style) port.

then if you're not happy, you can just make a new port, not have to start hacking up the wall.

meades isnt a plug.....

saywhat?
12-18-2006, 01:15 PM
12-13cubes NET

TUNE IT HIGHER!!!!!!!! It'll still sound good... tuning that low is stupid for this type of system.

Tune it 33-36hz... you have two 18's... they can handle the lows.

Port, 180-240 sq. in.

nG


that is what i have told him no lower than 33. its been shown that these subs dont exactly love a tuning much lower than that, and 33-36 they love. atleast in "normal" boxes.

iamamp3pimp
12-18-2006, 01:46 PM
wow, congrats on the walls. i didnt know u actually completed the other walls. I was just noticing different threads by you and it was referring to a wall.

Good luck on this one

same car, none were finished......

iamamp3pimp
12-18-2006, 01:49 PM
and i'd 35 it. a box this big, as well as the fact that these move a ton of air anyway will make up for it....you just have to be more careful to not unload them.

Kenny Pollock
12-18-2006, 02:30 PM
Not doing port plugs because of the time restraints... I'm looking to get it done by the 30th... so I'm settling for one port.

I'm not competing in dB drag or burping it... only daily/Bass Race. I can always cut the length to tune it higher...

vetkilr
12-18-2006, 03:19 PM
12-13cubes NET

TUNE IT HIGHER!!!!!!!! It'll still sound good... tuning that low is stupid for this type of system.

Tune it 33-36hz... you have two 18's... they can handle the lows.

Port, 180-240 sq. in.

nG

I was just gonna say that.Shouldnt be a problem not like your throwin alot of power to them.....prob 2K to 2200 watts max.

Did all you tuners account for the ports cubes when you did the tuning figures??

j3bus2k3
12-18-2006, 03:20 PM
I was just gonna say that.Shouldnt be a problem not like your throwin alot of power to them.....prob 2K to 2200 watts max.

Did all you tuners account for the ports cubes when you did the tuning figures??

Your referring to the numbers I put up? Yea, I took his gross, subtracted his sub displacment and physical port displacment as well as wood for the port. Then used the forumla off JL's site to come up with it...

saywhat?
12-18-2006, 03:23 PM
joel, he should be putting a little more than 2k per. but, real world numbers are more meaningful than rated, so who knows really. no one will till they are in the car and playing. should be loud regardless.

MikeyB
12-18-2006, 03:25 PM
12-13cubes NET

TUNE IT HIGHER!!!!!!!! It'll still sound good... tuning that low is stupid for this type of system.

Tune it 33-36hz... you have two 18's... they can handle the lows.

Port, 180-240 sq. in.

nG

Yeah I would definately tune it a bit higher, maybe 34, it will still hammer the lows, no doubt, and I would do atleast 200sq in of port area.

MikeyB
12-18-2006, 03:26 PM
Not doing port plugs because of the time restraints... I'm looking to get it done by the 30th... so I'm settling for one port.

I'm not competing in dB drag or burping it... only daily/Bass Race. I can always cut the length to tune it higher...

Tune it to 34, I promise.........

vetkilr
12-18-2006, 03:27 PM
joel, he should be putting a little more than 2k per. but, real world numbers are more meaningful than rated, so who knows really. no one will till they are in the car and playing. should be loud regardless.

Yeah think the same it will be loud eitherway............I would also stay under 15-20% of SD at least to avoid unloadin and tuning.

Kenny Pollock
12-18-2006, 03:49 PM
Yeah think the same it will be loud eitherway............I would also stay under 15-20% of SD at least to avoid unloadin and tuning.
What's SD?

vetkilr
12-18-2006, 04:18 PM
What's SD?
dual.7/dual1.4
Sd 1210cm^2 /1210 cm^2

CBFryman2
12-18-2006, 04:24 PM
Not doing port plugs because of the time restraints... I'm looking to get it done by the 30th... so I'm settling for one port.

I'm not competing in dB drag or burping it... only daily/Bass Race. I can always cut the length to tune it higher...


You say that now.:p:

In that case start with the longest port you an fit and shorten it untill you are flat and loud. Assumeing you have a TL on hand. 2.5 hours and maybe 10 sweeps and you will find your sweet spot.

And you can still do port plugs. Make your daily one and then when you have time after the 30th build another.

Kenny Pollock
12-18-2006, 04:26 PM
You say that now.:p:
I'll be running a bunch of 2400s, can't be in any Street class I don't think... lol

CBFryman2
12-18-2006, 04:28 PM
I'll be running a bunch of 2400s, can't be in any Street class I don't think... lol

1x competitons they dont really care. Doing dB Drag for fun is only an extra $10. They check woofers, walls, and amps.

iamamp3pimp
12-18-2006, 08:56 PM
SD = surface diameter = cone area

xluben
12-18-2006, 10:28 PM
Not doing port plugs because of the time restraints... I'm looking to get it done by the 30th... so I'm settling for one port.

I'm not competing in dB drag or burping it... only daily/Bass Race. I can always cut the length to tune it higher...

just cut a rectangle for now.

making a port shouldn't take more than than 20 minutes (probably less if you're already cutting/assembling mdf).

this way you won't cut it down to a 40hz tune for a comp you want to win, and then end up wanting your 30hz tuning back for the rest of the year.

dbornotdb
12-18-2006, 11:24 PM
Right now, the port is 183.6 square inches and I plan to have a 2 part port.
May suggest higher tuning so the 1st part will be 18" deep.
A 2nd, detachable part to the port will make it 30" deep as Nick @ Fi mentioned.


The people behindf the sub should know what works right?

xluben
12-18-2006, 11:31 PM
Right now, the port is 183.6 square inches and I plan to have a 2 part port.
May suggest higher tuning so the 1st part will be 18" deep.
A 2nd, detachable part to the port will make it 30" deep as Nick @ Fi mentioned.


The people behindf the sub should know what works right?


good to know there's some room for tinkering.

seems like kenny changes his mind a lot :D

(no offense at all, i do the same thing, but i can just see you being unhappy in a month or two when you have to do permanent changes to your port).

Kenny Pollock
12-18-2006, 11:40 PM
:p: No offense taken... it's true, I change my mind a lot more then I should... but this wall is final :)

xluben
12-18-2006, 11:43 PM
:p: No offense taken... it's true, I change my mind a lot more then I should... but this wall is final :)

wanna bet :evil: