Post by: Igor Mamuzic on September 29, 2004, 02:22:17 PM
Post by: Elliot Thompson on September 29, 2004, 06:16:19 PM
It is customary (And, out of respect to the Lab Members)
to have your real name listed somewhere in your post.
The JBL 2226H is a very versatile speaker. Meaning, it
can be used for a reflex, or horn-loaded enclosure.
It all depends on what kind of bass you are looking
for, and, what are the size requirements, for the enclosure.
Best Regards,
Post by: Igor Mamuzic on September 29, 2004, 07:36:19 PM
thank's
Post by: Elliot Thompson on September 29, 2004, 09:47:21 PM
As I mentioned in my previous post, the 2226 can be used
in a reflex or a horn. Its TS Parameters, are within the
crossroads of choice.
If you want sub bass, your looking along the lines of
the Lab Sub, in terms of size.
By you having only two of these drivers, you would be
better off with a reflex cabinet.
There are no 15 inch horn designs available that go
lower than 60 Hertz.
With A Reflex, you could get down to around, the low
40's with those speakers.
Of course, if you are up to the task, you can design
a 15 inch horn sub.
The Crown 1400 CSL is ruffly 500 watts @ 8 ohms, 750
watts @ 4 ohms. I'm guesing you are planning to run
one driver, on each channel of the amplier. Correct?
You can't Bridge it, for it won't handle 4 ohms in
Bridged Mode.
Post by: Nathan Lehouillier on September 30, 2004, 12:17:57 AM
but its really deep. I saw a couple of these in a dance club
they looked old but sounded great. I asked the guy running
the system and he said that they had 1X Gauss 15" in them
so your vented gap 2226 sould kick alot of butt in these
compared to the Gauss dino's. Est. 40x24x32 L,W,H
Good luck!
Post by: Igor Mamuzic on September 30, 2004, 10:57:52 AM
Post by: Tom Herr on September 30, 2004, 11:50:49 AM
I would also suggest you look for a pair of used EAW BH500's. They are a good match for those drivers.
Another option would be go to JBL's web site. They offer cab dimesions for their drivers as do most other major speaker companys.
Best of Luck
Tom Herr
Post by: Elliot Thompson on October 01, 2004, 07:08:27 AM
Here's a design that may work for your needs.
It would be best to contact the designer, for further
information. The horn was designed around the JBL
2226 H.
http://www.geocities.com/xobt/jblhorn.html
Best Regards,
Post by: raj on October 02, 2004, 01:30:30 AM
Can the 2226H s go as low as 40hz in scoops , and with four together they must be pretty good .
Does the power handling of the driver also increase in scoops ??
cheers
Rajeev
Post by: Michael_Elliston¶ on October 03, 2004, 12:32:42 AM
The 2226 design on my site-
http://www.geocities.com/xobt/jblhorn.html
That is just one of the designs. If you have a certain requirement i can model something up and CAD it
I just have a few questions
Boundarys- walls or on the ground
4 boxes you said each with 1 driver?
Power to be used?
Maximum size limit/volume
Low frequency extension vs Efficiency-whats important
eg lower F3 but 102db/1watt,or higher F3 and 109db/1watt
Im actually thinking of redesigning that horn to have a labhorn style of throat with wedge front chamber.
-Note that i havent built it yet
Cheers!
Mike.e
Post by: Tom Herr on October 04, 2004, 08:08:47 AM
4 scoops will go down to 40 hz. Of coarse that depends on the box design. The scoops I have are not JBL scoops. I built these about 10 years ago, from prints an associate had.
4 of them side by side do sound pretty good for what they are. However in a scoop there are phase issues. Sound from the back of the driver has a bit further to travel before exiting the cab vs the front.
As for power capacity. I have never run the numbers to see but I would think in the scoop there is less back pressure so probably no increase. Most likely a decrease. But the 2226 is a very tuff driver. Mine have a years of shows on them and I have yet to blow one.
Post by: Michael_Elliston¶ on October 05, 2004, 06:11:33 AM
Im sure that frontloaded will work better.
Cheers!
Post by: Alan Searchwell on October 05, 2004, 01:14:55 PM
Would your scoops happen to be the ones described on this page (link to plans near bottom of page):
http://www.dancetech.com/aa_dt_new/pa/15-scoop.cfm
This seems to be the closest to the scoops I have. Mine measure 24"x24"x42" externally and are loaded with 2226. I power them with either a QSC PLX 3002,PLX 3402 (two per channel) or a PLX 1602 bridged mono driving two. They do quite nicely when not pushed too hard, especially in groups of four or more. They do exhibit quite a bit of harmonic distortion when driven hard, the lowest octave seems to disappear and they begin to sound quite "boomy". One by itself is quite ineffective and I avoid using them as singles for all but the smallest of gigs. Another thing, if you pump too much very deep bass into these boxes with the 2226 it WILL destroy the driver. I discovered this after I got back a PLX from a rental and did not notice that the customer had switched off the 35Hz high pass filter. I had just re coned two 2226s and they didn't last the night.
I have received my LAB12s and bought most of the material to build four Lab subs. I expect them to be a substantial improvement over the eight scoops. I have been wondering if the scoops can work with the Labs if I make them do the duty above the crossover point of 80 Hz. I read somewhere that they are most efficient somewhere around 80Hz and drop to the efficiency of a normal front loaded box as you approach the mid frequencies. Any thoughts?
Post by: Tom Herr on October 05, 2004, 02:33:31 PM
Can't say for sure. But dimensions seem about right. I would have to find the prints and compare them. As I said before I built them about 10 years ago. Prints are most likely history.
If I remember right and it's been awhile since I have used them, I think I used to set the high pass at 40 hz. I origianlly powered them with big crown then later switched to QSC's 1 - RMX2450 bridged per pair. And ran them right up to clipping. Never had a driver fail. But I am quite sure without the high pass filter I would have experienced several failures. Loud but not so great in clarity. Mostly a function of the box. In a BH500 the 2226's sound very good, as well as in a proper front load box. However I would take labhorns over either, anyday.
I have built a lot of boxes of various designs. Some great some not so great. The labhorn is definately the best overall sub I have ever built. Very clean sound, fairly flat response in the intended range, efficient, high output, and very dependable, in my experience.
Post by: Michael_Elliston¶ on October 05, 2004, 10:28:32 PM
Playing with hornresp for 2minutes youl realise this.
Problems
1-Long rear loaded scoops have the inherent 'echo'delay from the two acoustic outputs
2-Lack of subsonic filtering
3-Lack of linearity due to no sealed box rear chamber-relies on driver spider(cms) linearity
4-Reactance annulling is impossible
5-Longer horn required for the same cutoff compared to Front loaded rear sealed horn.
Ofcourse a HPF deals with reducing the low freqs-but not with the linearity.
For Measurements on B1/Bzero/Labhorns see-
http://homepages.paradise.net.nz/sbk1/so/ssi.htm
With associated link.
Cheers!
Post by: raj on October 06, 2004, 01:45:51 AM
I like the sound of four scoops stacked side by side very much , inspite of all the DRAWBACKS of the design , they can produce earth shaking bass ,
I will say Old is Gold , also the size is average , another good feature is that almost any driver sounds good in a scoop , in my scoops I have double spider drivers , the sound is always open and even at full power the drivers are comfortable ,
Yes the new designs like the Lab Sub are definately better , we cannot compare the scoops to these , I want to make the Lab Subs but I would prefer a smaller enclosure as we mostly do small programmes, and cost of transportation is high .
Post by: Tim Padrick on October 22, 2004, 02:09:44 AM
Post by: Michael_Elliston¶ on October 24, 2004, 05:29:18 AM
If you input 600watts rms into a typical 40hz scoop the driver will have-
20mm excursion at 30hz
37mm excursion at 20hz
Where as with a rear chamber of appropriate size
13mm at 20hz
18mm at 30hz
So you can see why subsonic is so necessary
Also the nonlinear nature of the onesided horn comes into play at HIGH spl.
Youd have to have alot of path with efficient large mouthed horns.
Cheers!
Mike.e
Post by: raj on October 26, 2004, 01:53:03 AM
You are right the Labs will outperform the scoops,
but regarding transportation and handling ,
the size of a 15" scoop is nearly half of one Lab Sub , 15" scoop size is 24"x24"x41", and Lab sub size is 22"x45"x45".
Mike.e
Thanks for recomending 40hz subsonic filter , eirlear I was using 25hz there is much more headroom now .
Post by: Too Tall (Curtis H. List) on October 26, 2004, 11:30:19 AM
| mike_nz wrote on Tue, 05 October 2004 22:28 |
Problem!-Using generic designs for any driver doesnt guarantee good results!Especially with horn loaded enclosures!This was the whole point of the labhorn-To design the best driver possible for the required horn. Playing with hornresp for 2minutes youl realise this. Problems 1-Long rear loaded scoops have the inherent 'echo'delay from the two acoustic outputs 2-Lack of subsonic filtering 3-Lack of linearity due to no sealed box rear chamber-relies on driver spider(cms) linearity 4-Reactance annulling is impossible 5-Longer horn required for the same cutoff compared to Front loaded rear sealed horn. Ofcourse a HPF deals with reducing the low freqs-but not with the linearity. For Measurements on B1/Bzero/Labhorns see- http://homepages.paradise.net.nz/sbk1/so/ssi.htm With associated link. Cheers! |
Hi Mike,
When I went to your link I see you say you could not find the original site for the shootout. (And yes some of the files are BIG
The original Michigan subwoofer shootout page was hosted by John Sheerin. When he graduated he lost his website and Mattie Bien was kind enough to host it.
Here is the current address-
http://shootout.mattiebien.com/
As to the problems caused by combining the front wave and back wave in a sub enclosure there are some compromises made to gain the extra energy, but some people like the result.
The Bassmax speakers are easy to criticize when looking at both the impulse response and the frequency response (The hole caused in the high bass from cancellation), but when listening they sound very nice. I just sold some home speakers that use a 7" Peerless in a TL (Transmission Line) that have the same symptoms, but people love the way the bass sounds. This TL is very close to the Bassmax in some respects.
The main similarity is that the bass output from the back of the driver is a significant distance from the output on the front of the horn, never mind the length of the horn. Just looking at the actual exit points where it enters the room.
If you take those two sources and measure the cabinet at different places (an off axis polar pattern for instance) you will find that hole in the response changes to a peak, flat and then back to a hole depending on where you measure from. So the averaged "power response" to the room may be much smoother then it that one measurement shows. It certainly sounds like it when you listen in a room.
I personally still liked the LAB sub's sound better then the Bassmax. To me it sounded tighter and clearer. To the owners of the Bassmax speakers it sounded a little to sterile or as they put it The LAB sub has the "closed box" sound.
OTOH considering I was listening in a room with a fairly low ceiling and sidewalls causing lots of room modes I wonder if could really overcome my prejudice toward something I worked on and helped create.
In the end the only thing I can point to with certainty is the LAB subs went a little lower and a little louder down at its cutoff, while the Bassmax has a bump a little higher up.
For the people there anyone who could not do the woodwork to build a LAB thought the price and performance of the Bassmax was a worthy choice.
Post by: raj on October 27, 2004, 01:16:03 AM
The following is text by Elliot Thompson describing various ways of sub placement , tried out by Mark Seaton .
(( Posted by Elliot Thompson on September 02, 2003 at 03:47:26:
Hello All!
Here is my take on the Subwoofer Shootout held in Club
Blis, August 27, 2003
Servodrive BD 32
Let me be the first to say, the BD 32 was designed to use with some
kind of boundary
(preferably a wall) in which, it did not have, in the Subwoofer Shootout. I
wouldn’t say the Boundary Dependent 32 had a fair test. Kudos to Mark
Seaton that tried numerous configurations to give us an idea on what
was theory behind the BD 32. Since I arrived late, I missed the BD 32
calculated measurements. Paul if you have the numbers, please share
them with us. I heard three configurations. One using the all for BD 32’s
stacked two high, two wide, having the mouth’s exit couple together. The
amount of air pressure from the BD 32, is beyond belief. No one was
bold enough to stand in front of them, while they were in action. The air
pressure was just too great for the human ear to handle. The next
configuration was using two BD 32’s in a exponential fashion. Basically,
the configuration resembled this ^ Where the exit of the mouth would be
in the closed section, and, the cabinets were used as flares (Semi flare
so to speak) And, the final configuration had two BD 32’s facing each
other, and a third BD 32 blocking one exit path, having the sound
escaping in one direction. (More over like a tunnel path) Although, BD
32, was designed for a install or an esoteric home hi fidelity home
theater system (In my opinion), I still walked away very impressed with
BD 32. It’s a shame, the Basstech 7, and/or, Lab Subs never made it. ))
Post by: Michael_Elliston¶ on October 27, 2004, 11:10:29 AM
Yes i understand the interactions on the bassmaxx-usually it wont matter so much with LPF.
Im all for lowest distortion subs not musical ones
Even if the front loaded rear sealed design had a 'hard' sound -and the open back ones sound nicer - I dont care - I beleive in the absolute facts
35hz corner horn for my 2226 as soon as i can afford it!
Question
Hornresp shows,with increased mouth area(ie 2/4cabs in 2pi) that response does NOT go lower in frequency-but simply flatter and higher freq response. This is contrary to what many experience and say-that the stacks go lower! Are these 2 things different circumstances,although related.
Cheers!
Post by: Too Tall (Curtis H. List) on October 27, 2004, 01:43:33 PM
| mike_nz wrote on Wed, 27 October 2004 11:10 |
Hi Tootall Yes i understand the interactions on the bassmaxx-usually it wont matter so much with LPF. Im all for lowest distortion subs not musical ones Even if the front loaded rear sealed design had a 'hard' sound -and the open back ones sound nicer - I dont care - I beleive in the absolute facts 35hz corner horn for my 2226 as soon as i can afford it! Question Hornresp shows,with increased mouth area(ie 2/4cabs in 2pi) that response does NOT go lower in frequency-but simply flatter and higher freq response. This is contrary to what many experience and say-that the stacks go lower! Are these 2 things different circumstances,although related. Cheers! |
Well as the man said "I'm not a horn designer, but I have played one on TV!"
With that in mind if I'm understanding your question you feel that when you listen to a stack of JBL scoops they go lower, but the prediction software says no?
I would want to measure it to make sure your ears are telling the truth.
Also as you are playing with the horn program if the JBL horn design has some attribute like the length of the horn set to short, adding boxes in an array may not fix this.
Just a guess. I'm a Praxis and LspCAD kinda guy. The horn response programs give me a headache for some reason. I can build, measure and filter them, but not design them. The new LspCAD6 has a horn design program in it and I stay away from it too.
Post by: Elliot Thompson on October 27, 2004, 02:30:06 PM
Once you mentioned the Subwoofer Shootout, your name fell in place.
You should read the comments in regards to another topic,in
which, I had questions pertaining, Full Space Or Half Space.
It may answer some questions, when the need arises.
http://srforums.prosoundweb.com/index.php/t/2745/83/?SQ=07f7 192e74bf09960d5e2e2b2906d5a5
Too Tall
I want to appologize for calling you Triple J, in that post.
I was reading one of Triple J's post in the archives, and,
typing your reply as well.
Best Regards,
Post by: Michael_Elliston¶ on October 28, 2004, 06:47:07 AM
I 'know' that more horns = go lower and louder
But hornresp doesnt suggest this when you double/quadruple the mouth area represting another horn in the stack.
I design my horns long - but with 1/4 sized 2pi mouths.
I get a joiner to cut my sub boxes - design them and put them together
I know that with my jbl 35hz horn il have enough output-because my current box which is ~93db/1watt at 33hz is just loud enough -makes me deaf,but i know the horn will sound better in many ways and i have to try one
Interesting how EAW has the BH series with a 13ft horn with 2 12"s!
Our local club has 2 WSX bins in a 6x8m dancefloor its great! you can be physically vibrated! can hear the subs for a whole block away.
Can you get 33hz output(clean) with 4labs in 2pi space? Or was tom listing the Cutoff? The cutoff flare freq with front loaded rear sealed horns-the sealed rear chamber INCREASES excursion at cutoff but reduces it at lower freqs (compared to a scoop)
-so when you add the sealed rear chamber the frequency response graph LOOKS flatter- but if you look at excursion plot,that extra lows isnt usable at high power!
-Mcbeans program seems right in the low end.
Cheers!
Post by: Graeme Goodacre [Centauri on October 28, 2004, 08:04:42 AM
| mike_nz wrote on Thu, 28 October 2004 20:47 |
My problem is that my modeling program doesnt do what i expect- I 'know' that more horns = go lower and louder |
Hi Mike,
I think that because you hear more of the lows due to increased efficiency, it probably gives a subjective illusion of going lower even though the extension was actually there before.
The WSXs can certainly move some air, but the Lab should go lower - really depends on the program material.
I see by your drawing you have seen the pics of the Tuba30....
Cheers
Graeme
Post by: Too Tall (Curtis H. List) on October 28, 2004, 10:41:11 AM
| mike_nz wrote on Thu, 28 October 2004 06:47 |
My problem is that my modeling program doesnt do what i expect- I 'know' that more horns = go lower and louder But hornresp doesnt suggest this when you double/quadruple the mouth area represting another horn in the stack. I design my horns long - but with 1/4 sized 2pi mouths. |
Ok, so that is taken care of. I see one cabinet is designed to work with a much bigger horn mouth.
To an extent you see the same thing with the LAB sub. If you use one you need to use a filter to erase the wide peak around 70Hz or so. Then you have a fairly flat response down to about 33Hz. This is not 10dB or even 3dB down This is flat to 33hz, though you lost sensitivity to make it happen.
If you add more boxes to make a bigger mouth things stretch out and the peak gets wider and shallower while the response does not go a lot deeper. I think you are seeing the same thing.
I have to agree with Graeme. Like I said in a previous post you need to measure and not count only on your ears. As he states a simple level change will make you think you hear more low end.
Snip-
| mike_nz wrote on Thu, 28 October 2004 06:47 |
Can you get 33hz output(clean) with 4labs in 2pi space? Or was tom listing the Cutoff? |
You can hear 33Hz clean, clear and LOUD from a single horn out in the middle of a room. You have to watch out though because it is right at the tip of a very steep slope that can rip the driver to shreds if you let in anything under that. For a single box to be safe you need to put the high pass above that unless you know you will keep the SPL down.
Two boxes out in the open is much better bet and even then watch what you put into it. AL has been using a pair of subs for most of his work, but the material is centered more around 40Hz-60Hz. A rave calls for more cabinets or move the high pass up some.
The LABs sound great, but there is no magic involved.
Too Tall
Post by: Michael_Elliston¶ on October 28, 2004, 09:51:15 PM
Ive cut holes in MDF before-but circles with a holesaw are much easier.
I think that because you hear more of the lows due to increased efficiency, it probably gives a subjective illusion of going lower even though the extension was actually there before
The problem is also that its in texts like the Dinsdale horn files-im not sure about the Edgar horn files- but everyone says it so it must be true
? any word of this in the AES ?Cheers
Post by: Michael_Elliston¶ on October 28, 2004, 09:56:11 PM
The cone excursion peaks wildly at the Flare cutoff,but is perfectly fine just a few Hz lower
Im greatly interested in the facts-not peoples subjective experience they tell me 'Wow 4 of these boxes go way lower than 2!' and then i tell them ,well my modeling program is always correct in the low end - and it doesnt predict this-so Im glad youve told me your experience!
I think a users manual which is a MUST download for all people who download the plans-will get it-so that less drivers are destroyed! Its sad to see such wastage and annoyance caused by ill treatment and ill understanding users.
Cheers!
Mike.e
Post by: raj on October 30, 2004, 01:00:42 AM
Thanks the thread "Full Space Or Half Space." is interesting and informative
regards