The ETF (More here) is “THE”community where sharing audio ideas and adventures is DNA. I am proud to be a member, to share and learn more about my passion with some of the most imaginative and adventurous designers around.
This year, the organiser BA set a challenge to a few of the “lets make it happen” members of the ETF community. So the team was JC, SB, JJ, DS, BA, FS and myself, challenged to design a very unconventional system around my 13Audio replica Western Electric 12a horns. GIP Laboratory kindly gave us a pair of their very good 555w drivers that we knew were going to be challenged. (Big thanks to S. San). The WE12a horns had labels stamped to the event and the happy owner (JS in US) will have these at his home pretty soon. Thanks to JS for letting us use these before they ship.So this is a “real” collaborative work between USA, Germany, Sweden, Danemark, Korea and France based enthusiasts. Most of the team have extensive experience with high efficiency horns and the Western Electric “Big horns”. All know so very well that matching the dynamics and efficiency of these extraordinary sound beasts is “challenging”. This is no learners kind of adventure. As beyond the idea, the construction and building, it is about setting up for a 3 day event in Danemark….read on….After some debate it was decided not to take the conventional approach and hang the horns vertically. The choice was to place them on their sides, placing them lower and angled slightly outwards to achieve an even distribution of sound from the we12a horns for an audience of 200 ears. Bespoke stands were made to accommodate this solution.
We decided to go for a slot baffle using 8 x 15″ woofers wired series/parallel to achieve 4 ohms load for the amplifier. This solution gives way above 100db efficiency in the low end. The baffle was large…..and built on sight by BA. The aim was clearly to get 20hz to match the low end of the we12a. For the higher frequencies ribbon tweeters horn loaded added the extra touch. So unconventional as who’s seen ribbon tweeters on we12a horns before?..thanks JC!Amplifiers were made for the event by JJ and DS with adjustable high tension and filament voltages…a real Swiss knife that enalbled switching of input stage tubes and power tubes….Wow! Okay seen below it’s scary…but that’s what amplifier building is all about no? ….. beats the 100$ parts sold for 5000$ in a shiny box….anyway that’s another topic. The amplifier was designed for 100hz and above, beauty indeed! This allows some crazy materials to be used for the output transformers as they are running easy….some very good tricks using wonderful tubes indeed! Bass was a conventional amplifier suited to produce power and control of the 8 woofers rigged to 4 ohms. The tweeters had dedicated amplifiers from JC taking the signal from the mid/high tube amplifiers providing also level adjustment. A really simple yet crazy active xover using unconventional circuitry was made for the event designed to keep phase and signal in tune whilst offering level adjustment for the bass. A passive low pass was used to keep any frequencies from the bass units above 100hz away from the midrange, any of this will destroy the beautiful and unparalleled midrange of the Big Westren Electric horns.
That’s it…..a simple 3 way system….
The travel to the Vikings…..the ETF event took place in Danemark near to the Baltic Sea. That’s 1400km from my place here in Paris. A good friend DL offered his truck big enough to load the 2 x we12a horns and stands….its a 15 hours drive door to door. DL was invited and overwhelmed because of that. DL is another audio freak here in Europe….Nothing can get around the distance obstacle so we just did what we had to do….drive! So we set off at 4am to drive and arrived late evening. Actually it was a fun drive as another DD (another member of the gang) piggy backed the ride. So night, rain, snow and 3 audio freaks inside a truck for 15 hours…
We had some health truck drivers meals along the way. the challenge was a sausage in each country. We managed that! We all know that the Dane’s like to get the job done? Well I didn’t ! As soon as we arrived and after a short meal BA suggested we assemble the system….yes the Dane’s are the business! After 15 hours drive no time to waste! So…with DL and the help of good fellow ETFers that were already gathered there, we set to unload and assemble.BA had already built the baffle and bass units or maybe we can call it wall? Still lugging 100kgs horns after 15hours drive reminded me that I’m no longer 21 years old….it was fun and we all had a great laugh.We did manage that evening to connect the system up full range on the we12a, no bass no tweeter, with JC’s very own wicked 655o tubed unheard of design amps. A very nice relaxing session post big time efforts! Sleep was the reward! The morning was down to business! With JR looking over all of this….installing the tweeters and bass along with crossovers…FS brought along one of his treasures, CK threw in the phono stage and stepups and RtoR galore thanks to BA. All of this gear is top notch stuff…suited for such an event.Then tuning it all. Now we had here a bunch of guys who all know their stuff. Knowledge and hands on experience was in abundance. These are not some guys with opinions like the forum dwellers but users with deep foundations and solid backgrounds, still on road to push the limits into the territory of craziness. Obviously this enabled a “relatively” rapid 1st stage setup and then it was fine tuning. This was interrupted by the conferences that were held in the same room. So quite a bit of on and off…Those pauses were shared between assisting the conferences, meeting fellow ETFers and enjoying a few Danish beers. Guess beer is for setting up and wine for the listeners? No early to bed as the social ETF scene really comes into play post 23:00 hours. ETFers have a curious thing about them; we kind of lose the sense of time and even physical tiredness. This is taken to the next level when JR is around…and he was! So full days from 8ish to 3ish….did I say stamina? We are all recovering now as I write these lines.
So can an unconventional 3 way western electric horn system work? Can a wall of sound work? In short yes… at 90/100db listening to heavy metal, hard rock it was all singing fully articulate no perceived distortion. Jazz, vocals, classical and Opera….all good.
The shootout at the ETF was a comparison between live recordings of a classical trio that performed during the ETF event. The ETFers that participated in the shootout all came with their gear armed. No shortcuts taken and very different approaches adopted here leading to very different results. A real interesting aspect of our passion, another ETF thing….watching fellow ETFers placing microphones, adjusting levels etc….super stuff!
Now, the recordings they made were all astounding, and the 80 or so voters were all hard pressed and we went from 1/8’s to final. All the shootout was through the we12a based setup. The system enabled very immediate and distinct interpretation of each recording. The concert took place just a short while before the shootout. Everybody had the live concerts sound in mind. Hearing the same tones,sensing the room, the artists particular style and being able to imagine the placing of the microphones was all possible. So yes the system did work….
I must thank again BA and the ETF team for having made these events happen, by challenging the goals and realizing an international collaboration to meet those goals. The result setup is one thing, and now the system no longer exists. The strengthened relationships are all alive!