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Robert 2001
12-14-2011, 07:21 AM
Im looking to do a basic bandpass design or slot port box for 2 rf p1 10s. System will be running around 300 rms off an oldschool bazooka ela 300.1 mono amp. I would like to know what is the sealed to ported ratio on a bandpass box, how to tune to 32 hz,and same for slot port design/ opinions on both, and where to place ports. Box is going in a 2003 chevy tracker. thx

duanebro
12-14-2011, 09:24 AM
tuning on a 4th order bandpass box is normally much higher than ported. You need software like WinISD to model it if you want good results.

duanebro
12-14-2011, 10:05 AM
4BP Fb3 = 38-86hz
closed chamber = 1.3 cf
ported chamber = 1.5 cf
1 6" areo port 11.25" tuning is 57hz
All volume is net, you must make room for the drivers and port in the design.

Robert 2001
12-14-2011, 01:10 PM
Ok 2/1 ratio now how do I figure port size and tuning

Robert 2001
12-14-2011, 01:19 PM
Would a ported box work just as well? I wanna hit as low and hard as possible out of these subs. I currently have them sealed but have to build a new box as my wife blew the corner out in her box.

galacticmonkey
12-14-2011, 02:00 PM
I could design and build you a bandpass if you wanted. Im not too far away.

duanebro
12-14-2011, 07:01 PM
do a 2 to 1 ratio. 1.5 sealed and 3 ported. Tune to 50 or 55 hz. Invert eh subs , that will provide better cooling. Make the port as big as u can fit. That way it wont interfere and u wont have nearly as much port noise

how did you come up with this?

Robert 2001
12-15-2011, 06:25 AM
Anyone?

duanebro
12-15-2011, 08:22 AM
You can use WinISD to figure it out. This sub models better in a bandpass box than ported imo. Forget the ratio given in a post above. Modeling is the only way to go with higher order boxes. For this box use 1.3 cubes for the sealed side, and 1.5 net for the ported. A 6" "aero" port works well and is only 11.25" long.

any more info that you need?

Robert 2001
12-15-2011, 12:08 PM
I was wanting to do 2 ports 1 ea sub. Wanted to keep subs in seperate ported chambers and share the sealed space. Would something like a slot port on the ends of the box work for ports? Are the above dimenions for both subs. Would 2 cvr 10s do better I own a set of those and p1s wlith amps for both hangin out

duanebro
12-15-2011, 01:38 PM
They might be better I don't know. I don't have time to model it now. Ported boxes are much easier to build. If you want a design for the P1s ported I can draw something over the weekend.

Robert 2001
12-16-2011, 06:54 AM
Thatll work really wanted to do bp as I dont see many people running them. However im open to a ported as well as it would b an upgrade over a sealed/ blown out prefab. Still cant believe she blew the box out with p1s lol.

duanebro
12-16-2011, 07:46 AM
if you can, pm me Saturday, just so I don't forget. I can draw up a band pass if you want. But can you build it? LOL I just do 2d drawings btw, but they work.

Robert 2001
12-16-2011, 01:06 PM
If it can b made I can make it one way or another. I built current box in my sig with a sawzall on the tailgate was told l7s wouldnt fit. This winisd is it available for moble or home computer only.
.

duanebro
12-16-2011, 01:11 PM
pc only. it will show how a sub will respond to different boxes. It doesn't design the box, just volume, tuning... things like that.

Robert 2001
12-16-2011, 01:24 PM
Ill try to find it thanks for the help will get with u where can 1 find this

duanebro
12-16-2011, 01:31 PM
m.facebook.com/WinISD?refsrc=http%3A%2F%2Fwww.google.com%2Fm&_rdr

duanebro
12-16-2011, 01:34 PM
oops, that didn't work. they have a face book page. it is a beta - so there are issues. but it works great. you will need a guide to get you started.

duanebro
12-16-2011, 01:58 PM
What are the exact models and years on those subs?

brandinooooo
12-16-2011, 02:10 PM
The cvr's would hit better and lower. I have the perfect ported box design for cvr's. As for the p1's, you should just do ported as well.

duanebro
12-16-2011, 06:34 PM
cvr's are best ported, at least the new models. (that is what I looked at) could you post your perfect box Brandin?

wenn_du_weinst
12-16-2011, 06:53 PM
I sure hope you guys that are ''modeling'' are including cabin gain other wise it's much worse then experienced guesses

duanebro
12-16-2011, 09:01 PM
I sure hope you guys that are ''modeling'' are including cabin gain other wise it's much worse then experienced guesses

I'd like to pm you - but your mail box is full.

If you want SQ. you need to stick to sealed with these subs. That will give you the flattest fr. with cabin gain. For ported these subs won't have the sq of sealed. But they will be much louder. Just my 2 cents.

wenn_du_weinst
12-16-2011, 09:04 PM
they are gone now

duanebro
12-16-2011, 11:21 PM
How much space do you have for a box? I don't want to design a box that won't fit!
How big is the sealed box you have now? Just to compare to what I modeled. And did you like it before you blew it up?

Duane

duanebro
12-16-2011, 11:48 PM
http://i1091.photobucket.com/albums/i386/duanebrow/OptionsforFRP110.jpg

Ok, this is for one P1 @ 150 watts. (I know you will be using 2;))

The blue line is sealed response in 1cf. 80hz lp (Low pass crossover)

Green is ported 1.4cf tuned to 27hz (yes this is very low, It makes the FR roll off like a sealed box) 80hz lp

Red is band pass, about 1.3cf. NO lp filter.

I tried to make the boxes roll off to account for cabin gain. At first glance the ported box looks good. But it starts to roll off lower than the cg should start, so it could be "boomy." And unless you listen to music with bass lower than 41hz the band pass is louder. A single sub in the bandpass should be about as loud as 2 sealed. (In theory/on paper)

I'd like anyone with experience to give their opinion please.

Thank you,
Duane

brandinooooo
12-17-2011, 12:01 AM
http://i7.photobucket.com/albums/y253/scwolves10/NicksComp12s.png
http://i7.photobucket.com/albums/y253/scwolves10/cvr12.png

This was designed with cabin gain in mind (2001 Chevy Blazer SUV) which was about 52 (If I remember correctly). Somewhat flat response from 30 - 85 (LPF at 85). Not boomy or peaky at any frequency

duanebro
12-17-2011, 12:18 AM
This was designed with cabin gain in mind (2001 Chevy Blazer SUV) which was about 52 (If I remember correctly). Somewhat flat response from 30 - 85 (LPF at 85). Not boomy or peaky at any frequency

That looks close to what I have with the ported box. You should look into updating WinISD. It is being developed again. I found a link: http://www.linearteam.org/download/winisd-07x.exe

brandinooooo
12-17-2011, 12:32 AM
I have alpha but it fucks up too much and you can't add your speakers.

RAM_Designs
12-17-2011, 12:47 AM
You can add your own speakers with the Alpha version, I do it all the time. Follow the instructions on what order to enter the t/s and it makes it a lot easier.

brandinooooo
12-17-2011, 12:57 AM
Na I can't even add them on the alpha version I have. Unless they changed the location of the Add Speaker button or w/e it is. I didn't check it out too much because it always freezes

Robert 2001
12-17-2011, 01:27 PM
Ill have to measure I was figuring a ported box would b around 2.8 cu ft +disp.so ill prob end up around 3 cu ft finished. I had 2 12 in a prefab bp in it before. This is my wifes she likes the rfs for some reason there ok sealed nothin special though. The cvrs are in my pics old 300 rms ea. P1s are like 2 yrs old m ps410 150ea

J31Rob
12-17-2011, 01:28 PM
If you need software to build/design enclosures.. you're doing it wrong.

Robert 2001
12-17-2011, 01:58 PM
Tell me how u design a bp box .

duanebro
12-17-2011, 02:03 PM
If you need software to build/design enclosures.. you're doing it wrong.

Please, show me the right way! :D

TurboRedneck
12-17-2011, 02:39 PM
Fer a kwik instal i jess lay dem speekers bak der and hook dem wires inta dem. Dey rollz aroun da floor till da magnets fine sumtin metal ta sticks too.

Fer a speshul Hi-Fi seestem i uses wat da manufechtoors sejests an oftin sinds wit da speekerz. Da box dey come in'll do jess fine. Ya only needs a penseel fer pokin a hole in da backa da box fer da wirez. An anutha good part iz whin dey quits makin noize ya jess pull da wirez off'n takem backta Walmert.

-biLLy bOB

(no offense to anyone, just a voice in my head)

J31Rob
12-17-2011, 02:46 PM
Tell me how u design a bp box .


Please, show me the right way! :D

I have someone who knows what they're doing design it. You know.. those guys who did the **** before makeshift inaccurate software came out. :fyi:

Robert 2001
12-17-2011, 02:55 PM
Open to suggestion on how to diy guess yaall dont know cause noone has spoke up yet wanna talk smack about it but cant man up

duanebro
12-17-2011, 04:22 PM
I have someone who knows what they're doing design it. You know.. those guys who did the **** before makeshift inaccurate software came out. :fyi:

Lol, please answer the question. How do these guys know how to design a bp box? The software uses the same formulas as the old school. It is just much faster.

as far as the software being wrong, I have made a 6th order bp box and measured it, its fr was exactly like the model.

wenn_du_weinst
12-17-2011, 04:35 PM
if you think some one can design you any enclosure with out knowing the transfer function of your cabin your doing it wrong. Plenty of those old school guys pull **** out of their ***.

Robert 2001
12-17-2011, 11:46 PM
So far outer box dimensions 36 1/4 inches by 11inches deep by 14 inches tall aprox 3 cuft minus sub displacement of .085 ea sub how do I figure my port disp to tune said box btw box has 3/4 inch ceter divider ports to outsides.

Robert 2001
12-17-2011, 11:52 PM
Tuned around 30 to 32 hz.

duanebro
12-17-2011, 11:57 PM
If I read this correctly, you have two separate chambers, one for each sub?

Robert 2001
12-18-2011, 12:04 AM
Thats what I was planning on wanted to do bp but dont really know about it was going to chamber the subs in it as well.

disturbed471985
12-18-2011, 12:06 AM
Fer a kwik instal i jess lay dem speekers bak der and hook dem wires inta dem. Dey rollz aroun da floor till da magnets fine sumtin metal ta sticks too.

Fer a speshul Hi-Fi seestem i uses wat da manufechtoors sejests an oftin sinds wit da speekerz. Da box dey come in'll do jess fine. Ya only needs a penseel fer pokin a hole in da backa da box fer da wirez. An anutha good part iz whin dey quits makin noize ya jess pull da wirez off'n takem backta Walmert.

-biLLy bOB

(no offense to anyone, just a voice in my head)

Do what? English bro........ Dews u hera mez dozz..

Robert 2001
12-18-2011, 12:06 AM
Slot port on ends of box

duanebro
12-18-2011, 12:20 AM
As far as Band pass, this is what I have so far:
http://i1091.photobucket.com/albums/i386/duanebrow/Car%20Audio%20Designs/p14bpbeta1.jpg

The dotted line in the center are where the drivers go. I would angle these "walls" to make installing the subs easier. I did them strait to get the volume of the chambers correct first. The ports on the end are full height slot ports.

duanebro
12-18-2011, 12:23 AM
I'd use aero ports for the box you're building. Or square, if you use the whole height of the box for a slot port it will be really skinny or long.

fwiw 6"x 2" x 21.5" port is .22cf. 32hz box 1.3cf net

Robert 2001
12-18-2011, 12:36 AM
Could use like half of the height on the side or whwwatever skinny would make alot of noise was thinkin lik 3x7 port but not sure on length for tuning. What is the depth on that box

TurboRedneck
12-18-2011, 01:10 AM
Curious, what are you calling an "aero" port?...aka round? If so, they will cover design flaws on parallel side...rectangular boxes. Poking one in wherever you want never seems to pickup standing waves and works ok every time. However in my experiences a wooden slot port on a rectangular box have the possibility of being quiet if the ratios of W x L x H are not correct. Instead of memorizing the formula I angle a side. Usually it fits the vehicle better, picks up some lost cubic inches, and more visually appealing with an angled side too.

A slot port working in a rectangular box is a craps shoot but in the builders favor. Probably 7 of 8 will out perform a round port, so you've got good odds.

Remember to radius All corners of the port, Inside & out. So many skimp on the details, may as well bought a lesser quality sub.

Disturbed, congrats! You are not a redneck. Its ok, not everyone can be perfect. hehehe

duanebro
12-18-2011, 01:20 AM
Could use like half of the height on the side or whwwatever skinny would make alot of noise was thinkin lik 3x7 port but not sure on length for tuning. What is the depth on that box

The depth of the box is 12.5'.
I knew I needed to post that too!

6"x 2" x 21.5" port is .22cf. 32hz box 1.3cf net <--- this is for the box you posted, 3x7 would be longer yet and is not needed in this case, do to lower power.

duanebro
12-18-2011, 01:36 AM
Curious, what are you calling an "aero" port?...aka round? If so, they will cover design flaws on parallel side...rectangular boxes. Poking one in wherever you want never seems to pickup standing waves and works ok every time. However in my experiences a wooden slot port on a rectangular box have the possibility of being quiet if the ratios of W x L x H are not correct. Instead of memorizing the formula I angle a side. Usually it fits the vehicle better, picks up some lost cubic inches, and more visually appealing with an angled side too.

A slot port working in a rectangular box is a craps shoot but in the builders favor. Probably 7 of 8 will out perform a round port, so you've got good odds.

Remember to radius All corners of the port, Inside & out. So many skimp on the details, may as well bought a lesser quality sub.

Disturbed, congrats! You are not a redneck. Its ok, not everyone can be perfect. hehehe

Yes round, I thought that the golden ratio didn't make a difference if the wave lengths are longer than the box. This could be a problem in big boxes and full range speakers. (home audio mainly) If you get into very long boxes WinISD is off. It is a limit of the software. I have to have someone else model tower speakers for my house do to that.

And yes all corners need to be rounded, and I always flare the ends of the ports also. It helps a bit and looks nice.

Robert 2001
12-18-2011, 10:19 AM
Still debating on what to do really want to do bp trying to draw A 3d of the bp done it seems a little smaller than the ported doees that seem right?

duanebro
12-18-2011, 12:47 PM
Still debating on what to do really want to do bp trying to draw A 3d of the bp done it seems a little smaller than the ported doees that seem right?

It is smaller about 2.4-2.5cf, net. I designed it to try to give a fr of a sealed box, just louder. I had to keep the sealed part small to increase power handling. Then the ported chambers were sized to give me the fr I was going for.

duanebro
12-18-2011, 01:02 PM
as for what box to make - both! Try them out to see what you you like, and let me know what you like about both boxes, plus the sealed one too. If you go with the bp, throw the cvr 10s in the ported and sell it. (I don't think they will work as well in the bp box.)

Robert 2001
12-21-2011, 02:31 PM
I think ive made my mind up to do a ported instead of the bp at the moment may build the bp box if im not happy with output. Measurements 36 1/4 x 14 x 13. Port 14x1x11.44 for 32hz tuning sub disp .085 with a center divider box ends up 2.77 cu ft does this sound about right
? Opinions pls.

duanebro
12-21-2011, 03:25 PM
oops, I didn't look at where I was posting. I said the wrong thing. Sorry.

TurboRedneck
12-25-2011, 10:50 PM
I think ive made my mind up to do a ported instead of the bp at the moment may build the bp box if im not happy with output. Measurements 36 1/4 x 14 x 13. Port 14x1x11.44 for 32hz tuning sub disp .085 with a center divider box ends up 2.77 cu ft does this sound about right
? Opinions pls.

Your numbers are all within 10% of a box I'm very pleased with for CV 15's I did a couple weeks ago. I say let the wood fly, solid design.