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Bertha BH-882 Build

Printed From: Speakerplans.com
Category: Plans
Forum Name: New Projects Forum
Forum Description: Forum for new speakerplans projects, in memory of Tony Wilkes, 1953 - 2014
URL: https://forum.speakerplans.com/forum_posts.asp?TID=71222
Printed Date: 18 April 2024 at 4:58am
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Topic: Bertha BH-882 Build
Posted By: Audio_AL
Subject: Bertha BH-882 Build
Date Posted: 29 September 2012 at 4:35am
Been searching around for something big and loud and I think I found it :)
I am building two half Berthas and haven't decided on the extension yet but I may make that modular as well.

Drew out all the lines. Pop can to show the enormous size.

Side and back glued into place.

Alt view

First interior walls cut.

This is my poor mans CNC :) Its vinyl that would be used for lettering etc on vehicles/sign. I traced the circle and then cut with a jig saw. Works especially well on trapezoids and other non-circular shapes. Any sign shop should be able to cut these out for you if you have the dimensions, or just get ahold of me.

Poor mans cnc after tracing.

I had to get creative to make that steep cut and I didnt have any spare 2x4s without nails around.

I built the inside section separate so I could get screws and glue on easily.

Entire inside section being dry fit.

Entire inside section is built and the driver mounted. (B&C 18TBX100)

Looking into the 'Basshole' :D

More to come very soon.


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Make it loud!



Replies:
Posted By: specialjustin
Date Posted: 29 September 2012 at 5:52am
Get a little stooopid and pump that BASS!!
<iframe width="420" height="315" src="http://www.youtube.com/embed/qcOB9t7ECf8" frameborder="0" allowfullscreen></iframe>


Marvellous stuff!! 


Posted By: Ibex
Date Posted: 29 September 2012 at 9:03am
Please make sure to utilize the space between the first and the second horn flare in front of the rear chamber/driver!!!




Posted By: LjudLahger
Date Posted: 29 September 2012 at 12:03pm
Cool Clap


Posted By: Audio_AL
Date Posted: 29 September 2012 at 3:40pm
Ibex are you saying those two pointy parts are supposed to be part of the rear chamber?

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Make it loud!


Posted By: RealitySound
Date Posted: 29 September 2012 at 4:13pm
Originally posted by Audio_AL Audio_AL wrote:

Ibex are you saying those two pointy parts are supposed to be part of the rear chamber?


Looks like it to me.-


Great build so far!


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When you gonna send me some $$ mate ?


Posted By: T-Bone
Date Posted: 29 September 2012 at 4:24pm
That takes alot of guts to build a nice sounding BASS in YOUR FACE cabinet my hats are off for you! It will be a gut wrenching system so these are half size Emeralds as in GSA install? Nice . . .


BasssSSS! How low can you GO!Clap


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BASS, how low can you go!


Posted By: andycw
Date Posted: 29 September 2012 at 4:33pm
Looking good!

pop-up head lights in that motor! Cool


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No Bass No Fun


Posted By: MarjanM
Date Posted: 29 September 2012 at 11:34pm
Corvette?

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Marjan Milosevic
MM-Acoustics
www.mm-acoustics.com
https://www.facebook.com/pages/MM-Acoustics/608901282527713


Posted By: pfly
Date Posted: 29 September 2012 at 11:52pm
Corvette Stingray from mid seventies


Posted By: Audio_AL
Date Posted: 30 September 2012 at 5:02am
1980 Corvette T-top. Good for for raising hell on a Saturday night. ;)

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Make it loud!


Posted By: Audio_AL
Date Posted: 30 September 2012 at 7:09pm

View of the driver after being glued in place.

Outer shell in place.

Last side and 45 degree reflectors in place.

Got a little creative with the braces  :)

Braces from behind.

And a shot from the front.

Im hoping to have the top on and begin testing today. More pics soon.


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Make it loud!


Posted By: login4
Date Posted: 30 September 2012 at 7:39pm
they look loud, nice build 

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CELTIC SUBSONIC SOUND SYSTEMS


Posted By: Disturbance
Date Posted: 30 September 2012 at 8:04pm
Looking really good so far, nice work! Clap


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▬▬▬▬▬▬▬▬▬▬▬~ஜ۩۞۩ஜ~▬▬▬▬▬▬▬▬▬▬▬▬­­­­­­­­­­­­­­­­­­­­­­▬
              SHUT UP AND ENJOY THE MUSIC


Posted By: RealitySound
Date Posted: 30 September 2012 at 8:36pm
Love the 'bat-wing' braces Thumbs Up

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When you gonna send me some $$ mate ?


Posted By: Audio_AL
Date Posted: 01 October 2012 at 1:29am
:D I just got it all together and took it for a little test drive and all I can say is OMG. Im glad my closest neighbor lives over a mile away! Now for the extension. Muahahaha

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Make it loud!


Posted By: Audio_AL
Date Posted: 01 October 2012 at 4:16am
Here is the rest of the pics.




And here is a little teaser of what is to come. Approve


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Make it loud!


Posted By: T-Bone
Date Posted: 01 October 2012 at 6:14am
Just curious I wanted to build these years ago for pro PA subs, how did you come up with the plans half cabinet? Also what frequency will you be using and what amp to power? Why did you go with B&C ferrite 18" driver is this the closest to original custom Eminence woofer?

Thanks!Wink


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BASS, how low can you go!


Posted By: specialjustin
Date Posted: 01 October 2012 at 6:26am
Boy, you got some toys in that workshop. Careful you don't cause an avalanche!!


Posted By: Audio_AL
Date Posted: 01 October 2012 at 4:07pm
T-bone, i came up with the plans for the single driver version myself. It was no exact science. The height is approximately half of the two driver version. I do not have a set frequency yet. It sounds good at 120 and has even more punch when ran up to 140. I think it will depend on the specific situation and if i have dedicated kick bins down the road. As for the amp, i currently am using a behringer ep4000 :'( but i am in the market for something new and fancy (any suggestions anyone?). For the driver i had someone sim it and it performed very well. I also wanted a driver that i could put into a 186 horn if i need something with a smaller form factor.

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Make it loud!


Posted By: T-Bone
Date Posted: 01 October 2012 at 6:38pm
Nice build by the way, I may build a couple but these behemoths I know are going to be heavy with BB ply. I would use Crest 9001 or CA12 because this cab looks like it needs raw power. I remember the full size with the Levan Horn extension powered by Crown Macro 5000 in a club in NYC it shook my car parked outside the place. LOL!LOL

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BASS, how low can you go!


Posted By: Autograff
Date Posted: 02 October 2012 at 3:59pm

NICE (Car and Cabs LOL)

 
Would you be adverse to sharing the plans?


Posted By: RealitySound
Date Posted: 02 October 2012 at 5:37pm
http://hornplans.free.fr/bh882.html

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When you gonna send me some $$ mate ?


Posted By: Audio_AL
Date Posted: 03 October 2012 at 12:02am
To be perfectly honest with you guys one of these is more than i will probably ever need but i just picked up 5 more sheets so im hoping to have the next one done in a week or two. If you're wondering 'my' version takes about 3 3/4 4'*8' sheets. Ill have extra wood now for the extensions etc.

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Make it loud!


Posted By: T-Bone
Date Posted: 03 October 2012 at 12:43am
Audio_AL did you use Baltic Birch throughout the build? I was thinking of using Arauco (7plies) internals and exterior BB. I plan to build these, how many did you use for internals 4X8? I plan to use them for portable PA rig and maybe use Marc's MKB's. Any other driver you suggest I get real good pricing on Faital Pro Neo's. Thanks!Thumbs Up 

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BASS, how low can you go!


Posted By: Audio_AL
Date Posted: 03 October 2012 at 1:40am
Hello, I used all birch on mine. I'm not sure if it's Baltic or not. I never really kept track of internals vs externals but I think two sheet should do the inside. As for portability make sure you have the physical space and the man-power to move them around. 3.75 sheets @ 75lbs + 28lb driver makes this pig weigh ~310lbs! Check this thread out for a sim of a few different drivers. http://forum.speakerplans.com/eaw-bh-882-plots_topic33174_post709183.html?KW=Bh882#709183 . A great big thanks to Ibex for doing so!

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Make it loud!


Posted By: nomercy82
Date Posted: 26 October 2012 at 6:05pm
All of us bass heads wouls greatly appreciate your Extension Plans. I have 2 of the full sized cabinets, and an ep4000 running to them both. I RARELY get to use them because of their size. Mine are loaded with the Eminence Omega Pro 18a because they are cheap drivers and drop to 25 hz.

This is a thread where we discussed a ton of the RLA/ GSA/ SBS sound system stuff. Bertha Waldorf, Z array, and I'm still interested in the Levan extension.
http://forum.speakerplans.com/levan-horn-extension_topic58957_page1.html

Formalities aside, your build quality is great, and for all those others interested the name should say it all, Big Bertha ( mine atleast) are approcimately 365 pounds, but DAMN do they bring the bass.  The stories are true and I don't have the extensions...


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Building a system in Pennsylvania.


Posted By: Audio_AL
Date Posted: 26 October 2012 at 6:33pm
I havent had time yet to finish the extension but it will be built to spec. The only difference is it will be split into two pieces. As for the connection of all the hardware will be custom fabricated myself.

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Make it loud!


Posted By: nomercy82
Date Posted: 29 October 2012 at 11:04pm
Okay, I don't know the specs but in all the extensions I have seen. The outside edges are flat. GSA posted a picture of one being built on their facebook page. 

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Building a system in Pennsylvania.


Posted By: T-Bone
Date Posted: 11 November 2012 at 7:42pm
I want to build these 2 first then maybe another 2 down the road with the Levan extension, but I only want to use the Faital pro 18HP1020 18" woofer? Lower Qts at .28 but should be good and quick for horn loading? Since these will be used as part of a 4way system I plan to use a 11 ply 18mm lite ply light in color but tough as BB, weighs only 53 lbs per 4X8 sheet.
Audio_Al any progress soundwise? Do you have frequency response with and without the Levan extension? Thanks!


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BASS, how low can you go!


Posted By: nomercy82
Date Posted: 11 November 2012 at 11:16pm
I'd recommend against using drivers that are not suited to this application. In SOME horns you can get away with using a different driver than specified, but the BH 882 will turn cones to dust in a few thumps.  fire up hornRESP, and test that driver out just to be safe. Nothing is worse than getting a new toy and breaking it.

Bertha drops LOW, and it's LOUD. off the top of my head I believe the full sized EAW Bertha is a 138 dB continuous sub woofer with a -3 dB at 38Hz.   That's with out the flare, with the flare the -3 dB point is in the 25 Hz range. Put a pair side by side, and that response will drop even lower, question is can you driver do that?




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Building a system in Pennsylvania.


Posted By: Dub Specialist
Date Posted: 11 November 2012 at 11:26pm
serious build man..sorry its just your comment nomercy82 that the best saying ive heard for shredding drivers ever...


"but the BH 882 will turn cones to dust in a few thumps" 

lmao big time LOL..awesome dudeThumbs Up







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treat all creation with respect. For music is sound...sound is vibration...vibration is energy... and energy begets life. Therein lies my passion! MUSIC IS LIFE


Posted By: bitSmasher
Date Posted: 12 November 2012 at 12:11am
woah, obscene - make sure you weigh it!


Posted By: _djk_
Date Posted: 12 November 2012 at 12:31am
http://tcsounds.com/product/drivers/pro-5100-18-neo-driver/

30mm x-max, dual-laminated acrylic foam/fiberglass cone,$880.

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djk


Posted By: Goodvibetribe
Date Posted: 12 November 2012 at 12:46am
Nice work man, Seriously cant wait to see the extention once its finished.


Posted By: nomercy82
Date Posted: 12 November 2012 at 12:52am
Originally posted by _djk_ _djk_ wrote:

http://tcsounds.com/product/drivers/pro-5100-18-neo-driver/

30mm x-max, dual-laminated acrylic foam/fiberglass cone,$880.


Mother of God... You'd have to re-design the box to use that thing. the BH 882 only allows for something like 15 mm of xmax.

If you build with that driver, build 6 full sized bertha subs, DIY yourself some EAW DC1, buy a warehouse and retire a rich man.


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Building a system in Pennsylvania.


Posted By: marqsound
Date Posted: 13 November 2012 at 6:29pm
Nice build. What do you think about driving it with a Ciare 18.00SW?


Posted By: Audio_AL
Date Posted: 19 November 2012 at 6:01pm
Im sorry, marqsound. I am not familiar with that driver. Maybe someone with horn resp could help you.

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Make it loud!


Posted By: Audio_AL
Date Posted: 19 November 2012 at 6:19pm
I dont have any fancy hardware/software measuring equipment to make a plot but what everyone says about them is true. LOUD and LOW. And thats only with one half cabinet! I haven't got the second half-bertha or the extensions built yet but I will have them done by march for sure. I have a few high school proms that I want to use these at :). On second thought maybe I should just bring a 2*18BR so i dont get charged with sexual harassment!!

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Make it loud!


Posted By: T-Bone
Date Posted: 28 November 2012 at 5:27am
Any new updates on this project Audio_AL? Plan is to build these as soon as I finish my BF project, any new pics would be great plan is to use Faital 18HP1060 woofer. Thanks!Thumbs Up

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BASS, how low can you go!


Posted By: bitSmasher
Date Posted: 28 November 2012 at 7:21am
Originally posted by T-Bone T-Bone wrote:

BF project
Which BF is that?


Posted By: T-Bone
Date Posted: 28 November 2012 at 1:06pm
2 X Omni12TB, 2 SLAPro, and 4 Tuba 24 2 X 10" ( Eminence BP102)woofer each.Big smileBig smile

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BASS, how low can you go!


Posted By: Audio_AL
Date Posted: 28 November 2012 at 4:33pm
T-bone please be sure to add pics of those builds! As for my progress, im about 50% complete with my second 'Emerald' so any pics would be the same as whats already been posted. I will be sure to post pics here once i get to working on the extensions. Im hoping to make good progress this weekend.

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Make it loud!


Posted By: bitSmasher
Date Posted: 28 November 2012 at 11:29pm
Oh interesting T-Bone, want to start a thread on here documenting the process?
I'm half-interested in a few BFM designs (morbid curiousity perhaps) and the Omni12TB is one box I'd love to get opinion/measurements of


Posted By: _djk_
Date Posted: 29 November 2012 at 12:08am
(morbid curiousity perhaps)
 
Try laying down until the feeling passes.


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djk


Posted By: Audio_AL
Date Posted: 29 November 2012 at 12:37am
Originally posted by _djk_ _djk_ wrote:

(morbid curiousity perhaps)
Try laying down until the feeling passes.

LOL! There is quite a bit of negative feelings towards BFM designs. Not too sure why... Ermm


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Make it loud!


Posted By: b grade
Date Posted: 29 November 2012 at 1:53am
I have heard some of his boxes sounding pretty damn good.  I just don't like the dimensions.  Some of them seem reasonable, but don't have a skinny side to go through doors and others are just too tall and skinny.  I was going to build some titan 48s but instead I built 1850s.  Not unhappy with the decision.

Those Tuba 60s are lethal though.  Super loud and super low.  Way too big for most applications though.


Posted By: nomercy82
Date Posted: 29 November 2012 at 3:16pm
Sub shoot out: BFM Tuba 60 vs EAW BH 882. I know if you hook a macrotech 5000 vz to a bertha sub it's tremendously loud. talking shake your car outside the venue loud.


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Building a system in Pennsylvania.


Posted By: Audio_AL
Date Posted: 29 November 2012 at 3:34pm
hmmm maybe a T-60 is in order after I finish my emeralds and build different tops. Ermm

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Make it loud!


Posted By: T-Bone
Date Posted: 29 November 2012 at 9:07pm
Why T-60's because of the weight? Or is the Emeralds just too clunkie to have as a PA sub? They are heavy I must admit but classic sound bass and in your face! LOLLOL

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BASS, how low can you go!


Posted By: T-Bone
Date Posted: 30 November 2012 at 12:21am
Audio_Al I will try and post some pics Saturday am. I am driving to Miami tomorrow be back the evening. The 12TB's I just painted the front and will be painting the rest of the box when my Duratex base comes. I am going to tint the Duratex violet like Funktion-One. Also the subs are 80% complete just have to get more drivers my supplier ran out of the 4-ohm BP102. A friend is cutting the wood of the SLA Pro's as we speak for DJ monitor duties, will be building those soon too I should be done by the end of the year. My plan is for a large scale sound system 4 Emerald then attach the full Levan horn for large events for smallish events 2 Emeralds. Will be using the Faital Pro 18HP1060. I was also planning on building 4 each side of Simon's 3-way trap mid top on scaffold above the pair of Emeralds. This is the plan for early next year or may build 4 each side RCF copies of the 4Pro.Wink

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BASS, how low can you go!


Posted By: T-Bone
Date Posted: 01 December 2012 at 2:48pm
Here are the pics of my BF build almost done, this will be used for a 300 invited guest this February 11 sweet sixteen party. May use only two T24 24" wide 2 X BP102 loaded but plan is for all 4 T24'Wink
http://www.flickr.com/photos/60536137@N06/8234152947/in/photostream/
http://www.flickr.com/photos/60536137@N06/8235215704/in/photostream/
http://www.flickr.com/photos/60536137@N06/8234152307/in/photostream/
http://www.flickr.com/photos/60536137@N06/8234151941/in/photostream/
http://www.flickr.com/photos/60536137@N06/8234153411/in/photostream/


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BASS, how low can you go!


Posted By: mini-mad
Date Posted: 01 December 2012 at 2:59pm
im loving your "big purple" tops... what mid flares are they and where did you get them from.. please

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If it sounds like a gorilla is trying to escape, turn it down.


Posted By: T-Bone
Date Posted: 01 December 2012 at 8:46pm
mini-mad thats part of the plans I just put a bullet shape lathe turned wood in front of the phase plug which is a flat round disk per plan (TurbolikeWink). Takes an Eminence Alphalite 6A CBMR (500-3.5kHz) That is a Bill Fitzmaurice Omni 12TB plan, my next project maybe 8 Simon 3-way mid-top above 2 Half Bertha's like Audio_AL per side.Cool

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BASS, how low can you go!


Posted By: Audio_AL
Date Posted: 04 December 2012 at 4:31am
I went on a shopping spree today. :D Got a new amp, two more 18tbx100's and a fancy measuring system. I should be able to tell how low my half-bertha(s) is really going and at what spl by the end of the weekend.

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Make it loud!


Posted By: nomercy82
Date Posted: 04 December 2012 at 7:41pm
I am very interested in what your half berthas can really do. Especially with the flares. Your build is great. 

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Building a system in Pennsylvania.


Posted By: T-Bone
Date Posted: 04 December 2012 at 8:19pm
I've always wanted to build these, they are amazing with the Levan horn extension on full size Bertha. My plan is to build 4 half Berthas then attach a Levan horn when the need arises on large events. I am waiting Audio-AL for the result of your testing, will be using Faital Pro 18HP1060 neo woofer.Wink

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BASS, how low can you go!


Posted By: bitSmasher
Date Posted: 05 December 2012 at 11:03pm
Originally posted by bitSmasher bitSmasher wrote:

Oh interesting T-Bone, want to start a thread on here documenting the process?

T-Bone, can you start a new thread with those images and details - I want to discuss the BFM designs without derailing this too much further


Posted By: T-Bone
Date Posted: 06 December 2012 at 2:01am
bitSmasher I'll try tomorrow but don't hold your breath I work 12 hour shifts. I'll try to have it up tomorrow night if I am not working, thanks!

Keep Working Audio_AL on those Emeralds!!!!Clap


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BASS, how low can you go!


Posted By: Audio_AL
Date Posted: 06 December 2012 at 2:34am
Haha. I'm slowly peckin away at it. Kinda got held up on the interior section. It was all not square and outta wack. I think I got it figured out now tho. Ill have another look with a straight edge once the glue dries. 

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Make it loud!


Posted By: T-Bone
Date Posted: 06 December 2012 at 4:42am
Audio_AL I am dreamin' of a White Xmas here in Florida may happen but keep peckin'! Did you read about the Half Bertha in another site I think in Hornplans that if you raise the cab a little it will go lower response? I am trying to think where I read that.ErmmErmm

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BASS, how low can you go!


Posted By: midas
Date Posted: 31 December 2012 at 1:00am
I have got to build me some of those monsters! 


Posted By: T-Bone
Date Posted: 31 December 2012 at 1:03pm
I think two Emeralds would fill a school gym for Proms and what not! I am still contemplating and lookinf for Audio_Al's results, would like 4 X Emeralds loaded with Faital Pro 18HP1060. And extensions Levan Horn Full scale with 2 Emeralds.Wink

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BASS, how low can you go!


Posted By: Randall
Date Posted: 01 January 2013 at 4:47am
Hi Alek, after testing did you find much rattle with the bracing you've got, or do you think that's enough? Also, how did you attach the extension? I've been trying to come up with some sort of ratchet configuration, but at the moment nothings coming to mind

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It just feels like it's never quite loud enough...


Posted By: mykey-
Date Posted: 01 January 2013 at 5:23am
I designed a ratchet system years ago and it worked brilliantly. Super strong and assembled in less than a minute. All I had to do was buy an off the shelf piece and design and build the second part.


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BbbBBRAAAAPppBBBBbgushhhhhhhhssshhhhhGrAbRAAAAAAPPPPPp = Dubstep


Posted By: Randall
Date Posted: 01 January 2013 at 8:16am
I was thinking two of these across the front (top/bottom) to hold the levan sections together, and then another 1 either side to pull the extension to the cab

http://www.thomann.de/gb/stairville_zurrgurt_25mm_breit_x_4m_lang.htm?gclid=CNW_99HbxrQCFczHtAodrGoAqw


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It just feels like it's never quite loud enough...


Posted By: Audio_AL
Date Posted: 01 January 2013 at 7:59pm
Randall, I did not hear any vibrating/rattling in mine. The thing is built like a brick shit-house. I haven't got around to finishing my second one or finishing the extension yet Unhappy. As for attaching the extension I had in mind two peices of steel attached to the extension that would slide over each side of the cabinet and bolt (or t-nut or whatever) together. Not sure if this makes sense to anyone.Kinda hard to explain.

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Make it loud!


Posted By: Lee In Montreal
Date Posted: 31 January 2013 at 9:22pm
About to embark a similar build very soon. Loading them with some JBL 2242s. Making them 1 foot deeper though. The 3 extra ft of internal path will compensate for the Levan horn. They will be 5' wide by 4' deep.


Posted By: nomercy82
Date Posted: 31 January 2013 at 11:46pm
Post pictures when you're done. I'm curious about your design. How does a 1 foot extension of horn length make up for a 3 foot hyperbolic extension?

I'm not saying it doesn't I just want to see it.

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Building a system in Pennsylvania.


Posted By: Lee In Montreal
Date Posted: 01 February 2013 at 12:55am
Originally posted by nomercy82 nomercy82 wrote:

Post pictures when you're done. I'm curious about your design. How does a 1 foot extension of horn length make up for a 3 foot hyperbolic extension?

I'm not saying it doesn't I just want to see it.
  Very simple. You gain 1ft from the woofer to the front. Another foot from the front to the back and again 1 foot from the back to the mouth. That's all.


Posted By: nomercy82
Date Posted: 01 February 2013 at 3:03am
Excellent idea. Sounds great. Blow your crowds away.

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Building a system in Pennsylvania.


Posted By: Audio_AL
Date Posted: 01 February 2013 at 3:11am
Lee have you simmed this in Hornresp or a different program? Without changing the size of the mouth (among other things) wouldn't this totally change the tuning?

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Make it loud!


Posted By: Lee In Montreal
Date Posted: 01 February 2013 at 3:17am
Originally posted by Audio_AL Audio_AL wrote:

Lee have you simmed this in Hornresp or a different program? Without changing the size of the mouth (among other things) wouldn't this totally change the tuning?
What do you think happens when you add 3 feet of Levan horn in front of the Bertha?  ;-) I don't think people have to retune the throat when they add the Levan...


Posted By: Audio_AL
Date Posted: 01 February 2013 at 3:31am
What do you think happens when you add 3 feet of Levan horn in front of the Bertha? 

1) It's 3 feet in front of the horn as you have stated
2) Levan horn has a full 8' wide x ~22" tall mouth. Half Bertha has about 40" x 22" mouth.




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Make it loud!


Posted By: Lee In Montreal
Date Posted: 01 February 2013 at 5:08pm
3ft is the extra length. Wether you have into the extended cabinet, or in the Levan extension. The only difference is the mouth size. Considering that the same exact main box was used with and without the extension with a difference in path length and mouth perimeter, I wouldn't worry. Also, I doubt people will completely redo the main cabinet depending on if they have an old Eminence or RCF, a newer JBL 2240, a much newer JBL 2242 or the latest Radian. BTW I am not twisting anyone's arm here or pretending it won't make a difference. i'd rather do something unperfect than sit on my butt and watch the train passing bay... ;-)

BTW The main cabinet's mounth if used as a twin 18" woofer config is 2 x 20.5" wide by 46.5" tall. While the Levan horn can be anything you want. 8' wide or even 10' if you prefer. Ther has been many variations on the theme. Some were also 32" deep, some were 36" some were 48" deep. Pick your poison.

Also let's check a few basic specs of the EAW/Bertha.

Internal horn path is roughly 7,5 ft, which puts it in between a JBL 4530 (7ft) and a JBL 4520 (8ft). Nothing too exciting there with a primary 1/2 wave at 75Hz (peak response) and 1/4 wave at  38Hz. It is basically a "better" kick bin. Add the 3ft Levan extension and the new 1/2 wave goes down a bit at 55Hz. It gets better. But add another 3' of internal horn and then it gets really fun at 1/2 wave of 42Hz and 1/4 wave of 21Hz. At that stage, the limitation is the ability of the driver to go that low (but at least the woofer will be horn loaded until that low), and the mouth's perimeter.

Therefore, one can faithfully reproduce the cabinet as initially designed and live with its original specs. Or improve it to better fit newer musical content.


Posted By: Lee In Montreal
Date Posted: 03 February 2013 at 6:00pm
BTW Just to show that no design is set in stone, the Bertha started originally as an Electro Voice TL4050, then was added 6" in depth to become the EAW, and a few mods added. Therefore, what could keep anyone from modifying it to 42" or 48" deep to suit newer musics and newer drivers? The original Eminence woofer was a pretty flimsy and cheap $90.00 disposable woofer (not meant to be reconed at that price). Nothing compared to a $1000 JBL 2242 that can be substituted.




Posted By: Audio_AL
Date Posted: 03 February 2013 at 6:40pm
Yup. I know what u mean. I just wanted you to be sure what you were getting into before cutting up 5-6 sheets of ply. 3ft additional path length sounds pretty significant to me. Id still sim it before putting all that work into it. However, if u do get it built please report back here with your findings.

"i'd rather do something unperfect than sit on my butt and watch the train passing bay... ;-)"
I am the same way. I have built quite a few boxes that i knew weren't going to be perfect. But thats how i learn, by doing.
Peace.

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Make it loud!


Posted By: T-Bone
Date Posted: 03 February 2013 at 9:34pm
Nice to hear from you Audio_AL (AL is that Alabama?) If you have seen MOS restoration I plan on 4 Emeralds and GSA copies of the Imperial Horn (curved mouth panel) from decware.com 100-1kHz then JBL2360 then Bullets? Too may builds yet may start these in Spring.

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BASS, how low can you go!


Posted By: specialjustin
Date Posted: 03 February 2013 at 9:48pm
Boo hiss you edited it..


Posted By: Lee In Montreal
Date Posted: 03 February 2013 at 10:37pm
Bullets (or any other extra tweeters) are not needed with a JBL 2360. The 2360 only requires CD correction. 6db per octave from 3Khz.


Posted By: Audio_AL
Date Posted: 04 February 2013 at 2:23am
No, T-Bone. Im not from ALabama. AL is my nickname.

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Make it loud!


Posted By: Lee In Montreal
Date Posted: 04 February 2013 at 6:34pm
Originally posted by nomercy82 nomercy82 wrote:

Post pictures when you're done. I'm curious about your design. How does a 1 foot extension of horn length make up for a 3 foot hyperbolic extension?


Like that. With a 36" deep extension, it makes it "theorically" a 21Hz horn once the back chamber and throat size are tuned for a JBL 2242. Without the extension, it is a 27Hz horn for a 1/4 wave. Theorically. ;-)




Posted By: Lee In Montreal
Date Posted: 05 February 2013 at 3:01pm
BTW I wonder if I should open a new thread showing how a half-Bertha/Emerald can be used with two 15" drivers and cut (again) in half, making them very easy to move around as the new singles would be 48" deep x 30" wide x 24" tall. Four units with four 15" woofers would be the equivalent of two Emeralds with two 18" drivers.

Lee


Posted By: wafflesomd
Date Posted: 16 February 2013 at 2:41am
Originally posted by Audio_AL Audio_AL wrote:

T-bone, i came up with the plans for the single driver version myself. It was no exact science. The height is approximately half of the two driver version. I do not have a set frequency yet. It sounds good at 120 and has even more punch when ran up to 140. I think it will depend on the specific situation and if i have dedicated kick bins down the road. As for the amp, i currently am using a behringer ep4000 :'( but i am in the market for something new and fancy (any suggestions anyone?). For the driver i had someone sim it and it performed very well. I also wanted a driver that i could put into a 186 horn if i need something with a smaller form factor.


Don't frown that's a good amp.


Posted By: Laurin
Date Posted: 13 April 2013 at 12:24pm
Originally posted by Lee In Montreal Lee In Montreal wrote:

Originally posted by nomercy82 nomercy82 wrote:

Post pictures when you're done. I'm curious about your design. How does a 1 foot extension of horn length make up for a 3 foot hyperbolic extension?


Like that. With a 36" deep extension, it makes it "theorically" a 21Hz horn once the back chamber and throat size are tuned for a JBL 2242. Without the extension, it is a 27Hz horn for a 1/4 wave. Theorically. ;-)




Hey Lee Richard had something like this but 96" wide.
It was called the model D.

http://www.wavemusic.com/community/showthread.php?t=7511&highlight=emerald

My next step will be a version with two 21".  


Posted By: Lee In Montreal
Date Posted: 13 April 2013 at 12:33pm
A local shop has 96 x  2242H woofers at $299.00 a pop. i'm picking a pair this week to use with this project.


Posted By: MrZuarth
Date Posted: 13 August 2013 at 1:52am
Sorry a question, you did height of 21 inches?


Posted By: MrZuarth
Date Posted: 13 August 2013 at 1:53am
Sorry a question, you did height of 21 inches?
 
Originally posted by Audio_AL Audio_AL wrote:


View of the driver after being glued in place.

Outer shell in place.

Last side and 45 degree reflectors in place.

Got a little creative with the braces  :)

Braces from behind.

And a shot from the front.

Im hoping to have the top on and begin testing today. More pics soon.


Posted By: Audio_AL
Date Posted: 13 August 2013 at 3:59am
Originally posted by MrZuarth MrZuarth wrote:

Sorry a question, you did height of 21 inches?
  

I don't remember exactly but I think it was close to 21 inches Yes.


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Make it loud!


Posted By: CritikalMass
Date Posted: 21 October 2013 at 7:37pm
Update on the second build! Perhaps a video ?


Posted By: UpComingSound
Date Posted: 26 October 2016 at 2:28pm
Originally posted by MrZuarth MrZuarth wrote:

Audio AL how did these cabinets sound ?
Sorry a question, you did height of 21 inches?
 
Originally posted by Audio_AL Audio_AL wrote:


View of the driver after being glued in place.

Outer shell in place.

Last side and 45 degree reflectors in place.

Got a little creative with the braces  :)

Braces from behind.

And a shot from the front.

Im hoping to have the top on and begin testing today. More pics soon.


Posted By: UpComingSound
Date Posted: 26 October 2016 at 9:18pm
how do a single bertha compare to other single horn loaded 18 inch subs ?


Posted By: Lee In Montreal
Date Posted: 26 October 2016 at 10:14pm
The Bertha/Levan horn goes much lower.


Posted By: bob4
Date Posted: 27 October 2016 at 1:09pm
it's almost twice the size of a WSX...... Shocked


Posted By: Lee In Montreal
Date Posted: 27 October 2016 at 4:22pm
Sure, But nothing comes for free. Can't beat the laws of physics. To get deep bass, one needs larger volumes. And who cares if those bins are huge, they aren't meant to be moved around. ;-)

Lee


Posted By: Dub Specialist Sound
Date Posted: 27 October 2016 at 7:10pm
I love big speaker boxs

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Musical Roots Reggae Vibration is Life! for music is sound...sound is vibration...vibration is energy... and energy begets life. Therein lies my passion!...MUSIC IS LIFE...


Posted By: UpComingSound
Date Posted: 28 October 2016 at 12:47pm
so the single berthas would not be a good choice for mobile to have 4 of them compared to scoops or some other horn loaded cabinets ?


Posted By: Lee In Montreal
Date Posted: 28 October 2016 at 3:11pm
These Bertha's/Levan horns serve a different purpose than scoops. Look at most installations. Berthas + scoops on top for kick and upper bass. I suggest you build one and hear by yourself what you prefer. 

BTW This is a Waldorf on top of the Bertha in the picture, not a JBL 4520.






Posted By: UpComingSound
Date Posted: 31 October 2016 at 7:56pm
Here go some Berthas outside of met life center I believe DJs were the world famous disco twins from nyc    https://www.youtube.com/watch?v=xkhFbsAdQ0k" rel="nofollow - https://www.youtube.com/watch?v=xkhFbsAdQ0k


Posted By: parabox
Date Posted: 26 February 2017 at 7:35am
im somewhat intrested




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