Hi everyone, I was just wondering if anyone has any tips on porting a Folded Horn W-Bin cabinet. I've got 8 of these cabinets, 4 18 inch versions, and 4 15 inch versions, I've installed some ports in them based on port length recommendations from the software I used (winISD), it had all the T/S specs for the speakers pre loaded. I just wanted to make sure the same porting rules apply that you would use for a standard box. I just didn't know if having the port on the opposite side of the chamber as the baffle makes a difference in how to tune it or not.
Thanks
Glenn
Thanks
Glenn
Hey gjeff80 !!!! 😀
It's very easy to port a W Bin Enclosure. I did it myself with
the panel you would remove to insert the woofer.
What you need to do is scale the cabinet the woofer sits
in.
I'm currently using Bass Box Pro, and, Eminence Designer,
which offers a Pyramid, Truncated design. So........ I took
all the measurements, punched them in, and...............
It's very easy to port a W Bin Enclosure. I did it myself with
the panel you would remove to insert the woofer.
What you need to do is scale the cabinet the woofer sits
in.
I'm currently using Bass Box Pro, and, Eminence Designer,
which offers a Pyramid, Truncated design. So........ I took
all the measurements, punched them in, and...............
port
hmm... you guys have me thinking now... I shouldn't need special software that does pyramid boxes if I know the volume of the chamber right? I believe I found that correctly, I figured that out manually, all I did was take a measurement of the inside height, (h), the inside length of the two chamber walls (l), and then I took a measurement of the inside length of the front baffle (w1), and the small piece near the rear (w2), I averaged the two front and rear pieces ((w1+w2)/2) = (w) and that gave me my width, so then I just calculated box volume like a straight box, (l) x (w) x(h) / 1728.
My concerned was if you follow the same porting guidlines because the port is located on the rear of the driver. I just didn't know if it caused any problems because some of the sound is coming out of the front of the driver, and some is coming out of the port which isn't traveling out of the w-horn.
Thanks
Glenn
hmm... you guys have me thinking now... I shouldn't need special software that does pyramid boxes if I know the volume of the chamber right? I believe I found that correctly, I figured that out manually, all I did was take a measurement of the inside height, (h), the inside length of the two chamber walls (l), and then I took a measurement of the inside length of the front baffle (w1), and the small piece near the rear (w2), I averaged the two front and rear pieces ((w1+w2)/2) = (w) and that gave me my width, so then I just calculated box volume like a straight box, (l) x (w) x(h) / 1728.
My concerned was if you follow the same porting guidlines because the port is located on the rear of the driver. I just didn't know if it caused any problems because some of the sound is coming out of the front of the driver, and some is coming out of the port which isn't traveling out of the w-horn.
Thanks
Glenn
The aim of porting a horn is to extend the low end, therefore if your horn's lower cutoff was say 50Hz (some compact W's are even higher than this), then try port tuning at 35-40Hz. Also be aware that horn loading a driver lowers the driver's Fs - estimate around 10% lower. The horn output at the port frequency usually drops off quite rapidly, so time arrival problems would be minimal - just don't try tuning the port too high. You may find that the required port length (taking into consideration port air speed) could be way too long to physically fit.
Cheers
Cheers
It makes no difference tuning wise.
The only concern with having the ports at the rear would
be designing cabinets for stacking, say four or more.
Rear porting in this case is not a good idea, a shelf port
to the front of the cabinet, top or bottom, should be used.
🙂 sreten.
Thanks, I've been tuning all the W-Bin pors to 40Hz, and went with the length ports winISD recommended I use. I'm running JBL 2226H speakers in the 15 inch w-bins, they used to be sealed, but the internal volume of the chamber is only 2.6~2.7 cubic feet, so I felt they were being restricted by being in such a small enclosure, so I installed 4 2 inch ports with a length of 6.5 in each box, which was what winISD said would tune the port to 40Hz.
Then one set of the 18 inch w-bin sets is loaded with a JBL 2240H woofer, the internal volume of this chamber is about 7.65 cubic feet, again I tuned this cabinets port to 40Hz.
Then the last set of 18 inch w-bin's I haven't ported yet since I just finished one of them. It's JBL's 4518 cabinet, I'm going to try an extra set of Cervin Vega 189E woofers I have sitting around, but I'm waiting to see if I can find the T/S specs, or measure them so I can plug the parameters into a box building software.
Does 40Hz sound about right for tuning the port too, according to the graph on WinISD it seemed to provide the best looking graph for the woofers. Also, how accurate is the graph that WinISD generates, I know it is based on a regular front loaded box, but how much will a W-Bin Horn affect the graph, will it still have the same curve just with increased dBs?
Thanks again guys!!
Then one set of the 18 inch w-bin sets is loaded with a JBL 2240H woofer, the internal volume of this chamber is about 7.65 cubic feet, again I tuned this cabinets port to 40Hz.
Then the last set of 18 inch w-bin's I haven't ported yet since I just finished one of them. It's JBL's 4518 cabinet, I'm going to try an extra set of Cervin Vega 189E woofers I have sitting around, but I'm waiting to see if I can find the T/S specs, or measure them so I can plug the parameters into a box building software.
Does 40Hz sound about right for tuning the port too, according to the graph on WinISD it seemed to provide the best looking graph for the woofers. Also, how accurate is the graph that WinISD generates, I know it is based on a regular front loaded box, but how much will a W-Bin Horn affect the graph, will it still have the same curve just with increased dBs?
Thanks again guys!!
W Bins is a straight horn folded to take up less space.
You cannot just tune the box to a desired frequency until,
you know how the speaker will respond tuned to that
desired frequency in the enclosure.
Horn woofers TS Parameters are totaly different from
Bass Reflex woofers, and, you can't tune a Woofer
using bass reflex equations to work with a horn woofer.
You cannot just tune the box to a desired frequency until,
you know how the speaker will respond tuned to that
desired frequency in the enclosure.
Horn woofers TS Parameters are totaly different from
Bass Reflex woofers, and, you can't tune a Woofer
using bass reflex equations to work with a horn woofer.
Omniflex,
Do you know how I would go about tuning the port of a folded horn if i know the T/S specs for the woofer? I thought of leaving the cabinets sealed, but the majority of the W-Bin boxes I found online all had some type of port installed in in the front piece. I guess tuning them is a lot more complicated than I thought.
Thanks again for all your help on my posts!
Glenn
Do you know how I would go about tuning the port of a folded horn if i know the T/S specs for the woofer? I thought of leaving the cabinets sealed, but the majority of the W-Bin boxes I found online all had some type of port installed in in the front piece. I guess tuning them is a lot more complicated than I thought.
Thanks again for all your help on my posts!
Glenn
Yes I know how to it.
I explained it to you on my first reply.
Dude, I own four W Bins, all housed with Cerwin Vega
Eighteens.
They are tuned to 52.37 Hz, and, have a f3 @ 50 Hz (RED)
If I kept them sealed, the f3 would be 141 Hz. (YELLOW)
I cut them off at 50 Hz, and are tuned on 100 Hz. With
the help of a Electronic Crossover of course!
I explained it to you on my first reply.
Dude, I own four W Bins, all housed with Cerwin Vega
Eighteens.
They are tuned to 52.37 Hz, and, have a f3 @ 50 Hz (RED)
If I kept them sealed, the f3 would be 141 Hz. (YELLOW)
I cut them off at 50 Hz, and are tuned on 100 Hz. With
the help of a Electronic Crossover of course!
Attachments
Omnifex,
Thanks, here is the graph I got using winISD, but I just got confused by your previous post saying how you can't simply tune the enclosure without knowing how a speaker would response to that speaker. This woofer is a JBL 2240H, basically what I did here, was loaded up winISD, select the 2240H, select a vented enclosure, entered in the volume of the chamber 7.65, then said tune the port to 40Hz, and I used 3 3 inch ports, and it said to make them length 2.38 inches, and it gave a vent mach of .05.
The yellow line was a sealed enclosure, and the green line is the ported enclosure??
Did I do this wrong?
Thanks, here is the graph I got using winISD, but I just got confused by your previous post saying how you can't simply tune the enclosure without knowing how a speaker would response to that speaker. This woofer is a JBL 2240H, basically what I did here, was loaded up winISD, select the 2240H, select a vented enclosure, entered in the volume of the chamber 7.65, then said tune the port to 40Hz, and I used 3 3 inch ports, and it said to make them length 2.38 inches, and it gave a vent mach of .05.
The yellow line was a sealed enclosure, and the green line is the ported enclosure??
Did I do this wrong?
An externally hosted image should be here but it was not working when we last tested it.
I can't see your graph. All I see is a red X 
7.65 Cubic feet is a good size for a single 18 inch driver.
My internal chamber in my W's are 4 cubic feet.
You must have some huge horns!!!!!
Just keep in mind that if you're planning to use all
the horns together, They must be tuned to the
same frequency, and have almost the same cut off
response.Or, they will cancel each other out
(Phase problems)
7.65 Cubic feet is a good size for a single 18 inch driver.
My internal chamber in my W's are 4 cubic feet.
You must have some huge horns!!!!!
Just keep in mind that if you're planning to use all
the horns together, They must be tuned to the
same frequency, and have almost the same cut off
response.Or, they will cancel each other out
(Phase problems)
hmm, let me reupload the picture to my webspace, it was working last night.
The first 18 inch w-bin cabs I had, we got from someone, I don't know if they are a name brand, they are built really well, all miter cuts, they were HUGE, they were 4ft, (w) by 4ft (d), by 20inches (h). They must have had an internal chamber volume of about 10ft or something, but they were just too large to move around, they wouldn't even fit down the basement stairs. So we ended up cutting them down to 36 deep, which only changed the internal volume to about 7.65 cubic feet, and probably made the mouth of the horn 5 inches smaller or so on each side of the center. But atleast they are movable now. I figured that all the cabs would have to be tuned to the same frequency, so I've been using 40Hz for all the boxes because that seemed to give the best response because I'm crossing them over at the crossover at 100Hz, and 40Hz seemed to give flatest response with a lower response then if I tried porting them into the 50 Hz range.
-Glenn
The first 18 inch w-bin cabs I had, we got from someone, I don't know if they are a name brand, they are built really well, all miter cuts, they were HUGE, they were 4ft, (w) by 4ft (d), by 20inches (h). They must have had an internal chamber volume of about 10ft or something, but they were just too large to move around, they wouldn't even fit down the basement stairs. So we ended up cutting them down to 36 deep, which only changed the internal volume to about 7.65 cubic feet, and probably made the mouth of the horn 5 inches smaller or so on each side of the center. But atleast they are movable now. I figured that all the cabs would have to be tuned to the same frequency, so I've been using 40Hz for all the boxes because that seemed to give the best response because I'm crossing them over at the crossover at 100Hz, and 40Hz seemed to give flatest response with a lower response then if I tried porting them into the 50 Hz range.
-Glenn
Ok Glenn, All Systems Go ! 😀
Hmm............
Its obvious the 2240 will perform much better in a
reflex than sealed. It exceeds in SPL, low frequency
extension in -3 dB, and, -10 dB over the sealed
chamber.
So, you have the B 48's!!! Those were designed for
the movie Earthquake in the 70's by Cerwin Vega.
I believe the 189 was the Driver used in this cab.
The JBL 2240 replaced the K 151 which was used
in Don Keele's horn.
I'm using the smaller version to the B 48's (24 inches
deep)
The next thing you need to do, is see if the port noise
will be too noisy. I believe you can add the amount of
wattage you're planning to use on WinSID so you can
see how much port noise the vent will make. You may
need to play with the ports size, and, length to reduce
the port noise under High SPL's.
Hmm............
Its obvious the 2240 will perform much better in a
reflex than sealed. It exceeds in SPL, low frequency
extension in -3 dB, and, -10 dB over the sealed
chamber.
So, you have the B 48's!!! Those were designed for
the movie Earthquake in the 70's by Cerwin Vega.
I believe the 189 was the Driver used in this cab.
The JBL 2240 replaced the K 151 which was used
in Don Keele's horn.
I'm using the smaller version to the B 48's (24 inches
deep)
The next thing you need to do, is see if the port noise
will be too noisy. I believe you can add the amount of
wattage you're planning to use on WinSID so you can
see how much port noise the vent will make. You may
need to play with the ports size, and, length to reduce
the port noise under High SPL's.
Omniflex, is a ported box concidered a "reflex" box? Those must be the B36's I have, I got 3 of them from someone, two were loaded with CV-189E's, and then the other one had a McCauley 18 in it. Neadless to say, they were all blown at the time, so we got some JBL 2240's and put them in the cabs and ran them in a club for a few years, before it closed down. Then when the club closed, we decided to cut them down to 3 feet in length so they could be more portable. Then just recently somene gave me one of JBL's 4518 (Don Keele's) W-Bin Horn, so I just made another one this past week, the plans were online, and easy to follow, I was thinking of loading those two cabinets with the CV-189E's once I get them reconed, and I'll have to figure out the T/S specs and hopefully can figure out what size port to install.
winISD used the PE when it figured out the port Mach, it will show a number in either green or red, I believe for this cabinet it had a Mach of .05, which was good I was told, but I wanted to use 3 inch diameter ports, so I had to use 3 of them at a length of 2.33 inches to get this Mach. I think in the help file they said this has to do with the noise of the port, I think it said below .11 or something you don't have any problems with noise.
Thanks again
Glenn
winISD used the PE when it figured out the port Mach, it will show a number in either green or red, I believe for this cabinet it had a Mach of .05, which was good I was told, but I wanted to use 3 inch diameter ports, so I had to use 3 of them at a length of 2.33 inches to get this Mach. I think in the help file they said this has to do with the noise of the port, I think it said below .11 or something you don't have any problems with noise.
Thanks again
Glenn
Next time upload a TINY image such as this one-saves time waiting
yes.
use winisd pro it shows a graph of airspeed and is more likely to be assuredly accurate.
If horns do this- what about ported boxes or sealed boxes for that matter,are not cancelling each other out simply because they are tuned to different frequencies.
assuming one plays the same input polarity into each- then each will produce the output-with whatever phase distortions-but not 180* out like u say...
I fail to see your reasoning,but no woofer will be phase accurate.
(as i understand it)
Cheers!🙂
Attachments
mikee12345
Have two cabinets. One tuned at 40Hz, one tuned at 30Hz.
Feed a signal that has alot of 35 Hz emphisis. The cabinet
tuned at 40 Hz, will be out of phase with the box tuned at
30 Hz.
This is why, it is essential to use the same tuning when
using multiple enclosures.
Sealed cabinets are never out of phase. However, once you
go below the tuning frequency, you will encounter phase
shifts.
Have two cabinets. One tuned at 40Hz, one tuned at 30Hz.
Feed a signal that has alot of 35 Hz emphisis. The cabinet
tuned at 40 Hz, will be out of phase with the box tuned at
30 Hz.
This is why, it is essential to use the same tuning when
using multiple enclosures.
Sealed cabinets are never out of phase. However, once you
go below the tuning frequency, you will encounter phase
shifts.
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