I stumbled upon these renderings/plans and i am pretty darn sure that these are the subs used in the GSA system at district 36 in nyc. The bass from 4 of these on a small(ish) dance floor is unreal!! As i mentioned in another thread, this system produces the strongest bass i have ever heard! (i've been to my fair share of clubs with good systems installed)
here they are, the EAW bertha...
here they are in the GSA stack...
and im pretty sure Gary Stewart uses the crown 5002 to power each one...so with two woofers and bridged on that amp i figure about 5000rms?
obviously these are permanent install only and they are not meant to be moved around at all.
here they are, the EAW bertha...
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
here they are in the GSA stack...
An externally hosted image should be here but it was not working when we last tested it.
and im pretty sure Gary Stewart uses the crown 5002 to power each one...so with two woofers and bridged on that amp i figure about 5000rms?
obviously these are permanent install only and they are not meant to be moved around at all.
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The most powerful bass I have ever heard, or feared my internal organs would explode, was 4 BDEAPS, 2 over 2 powered by a PL9 at Paul Bells club in NYC. Mark Seaton was driving and had a techno beat pumping that not one in attendance was brave enough to walk within 10 feet of. I walked the room and the bass was even throughout. Clean to 40hz at full output, first time Paul lost a bottle off the bar shelf and popped a breaker.
I worked with Richard Long in 1985. The bass box is called Bertha and the extension with a 96 x 42 inch mouth is called a Levan (after Leroy Levan). The drivers were custom made Eminince 18's - maybe some RCF 's later . There were also a few Levan's built with 120 inch x 42 inch mouths with a third bend . (I worked iwth Richard on a club called the Copa in Toronto with 4 of the 120 inch Levan's that were double stacked for a 10 foot x 84 inch mouth). Sometimes Richard made the Bertha's or EAW made some for him as well. The 10 foot mouth was only ever made by Richard - i gave him a hand in his NYC shop for a day doing the final cuts of the mouths for the Copa. The Bertha/Levans are run 20 to 100hz on an effects output with a gain and cut control on the RLA 3000
The problem with the GSA system is the phase cancellation on the 15 inch low mid box where the horn loaded back radiation meets the direct radiator 15's output. - maybe about 250 to 400Hz range ) It was better done by Richard with 2 of 2 x 15 inch fully horn load bent front loaded bass horns running 40 to 250 HZ per stack and then a 250hz crossover to the double D 2 x 12 inch horn ( RCF ) with large long phase plugs Richard called the Double Dildo before crossing to the JBL 2395's at 1200 Hz which ran full range while the 2402 JBLs ran off the RLA 3000 crossover from 7 K and up on an effects output of the RLA 3000 crossover . The second problem with the GSA's 15 inch box is they don't go down to 40 HZ which was needed for the crossover points Richard used, but they may well have thier own crossover points based on their driver choices and cabinet design.
The problem with the GSA system is the phase cancellation on the 15 inch low mid box where the horn loaded back radiation meets the direct radiator 15's output. - maybe about 250 to 400Hz range ) It was better done by Richard with 2 of 2 x 15 inch fully horn load bent front loaded bass horns running 40 to 250 HZ per stack and then a 250hz crossover to the double D 2 x 12 inch horn ( RCF ) with large long phase plugs Richard called the Double Dildo before crossing to the JBL 2395's at 1200 Hz which ran full range while the 2402 JBLs ran off the RLA 3000 crossover from 7 K and up on an effects output of the RLA 3000 crossover . The second problem with the GSA's 15 inch box is they don't go down to 40 HZ which was needed for the crossover points Richard used, but they may well have thier own crossover points based on their driver choices and cabinet design.
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the are rear loaded low mids.
seems a bit odd to use rear loaded for lowmids.
i suggest to use fronloaded for lowmids.
imo
They're doing that so the mid can cover an extended range - like the single-driver folks like to do for hi-fi. Front loaders will work better if you use a separate high and low mid (the low can be folded). This of course gets rid of all the phase cancellation problems you can get with rear loaders.
ihv just known tu has many friends are betterLOL thx 4 2. i loved buffterfly bin because it was beautiful. ok if Flh is beter ill change to it. but see on Elephant mouth w-bin ok beautiful as the same but very big. and i'm afraid of the phase problem when use together with the other low bin.thx again
Original RLA Bertha JBL4550A's all vintage loaded
Hi. I have come across a huge original RLA Bertha subwoofer. Also there are 4 JBL 4550a's. They have JBL speakers model: 2225H. Consecutive serial numbers on the one I opened up. Putting up for sale/trade. My email is Ldawns@msn.com . Thanks
Hi. I have come across a huge original RLA Bertha subwoofer. Also there are 4 JBL 4550a's. They have JBL speakers model: 2225H. Consecutive serial numbers on the one I opened up. Putting up for sale/trade. My email is Ldawns@msn.com . Thanks
I just recently obtained these and am not knowledgeable about them, other than what I have researched. When you mentioned mouth extension, I looked up what it meant. That's how ignorant I am about these. But I did find there are a lot of "old school'ers" that prefer them. I see ads for the cabinets but without speakers. These all have speakers in them. They are JBL 2225H's. The one speaker I took the back off of had 2 with consecutive serial numbers. But I'm learning more every day.