How many people on the planet have played with the 12a and 13a? I know quite a few of them….and so many forum dwellers out here are saying that the 12a and and 13a we’re designed so that the 12a did the highs and the we13a the low. This is a misconception stemming from a misunderstanding of frequency range of that era….these installations were not for THX or dolby nor for soundtracks from Diehard etc…..nope!
Extensive study of the history and available documentation enabled me to have learnt that the 12a and 13a were installed in large theatres as permanent installation and placed to enable the theatre to be used for live representations with orchestra etc..
These large theatres has orchestra level seats and balcony as we know.
The 12a was installed high up at the every top edge of the scene, the 13a in the pit. The 12a was for the balcony seats and the 13a for orchestra level seats. The signal sent to all the horns was the same. Sort of multi channel mono. The frequency response in 1926 was maybe 80hz to 5000hz?….the 12a goes down to 100hz easy as I have seen from Suzuki San’s (GIP laboratory) readings…and my ears! The 13a….ever easier!
If you study (I have) the installation schema for the 12a and 13a you will notice that the 13a had an autoformer to adjust the level. This was to balance the 12a no 13a levels in the theatre. No filters were used at all.
Once you hear the 13a you will realise that it needs no 12a at all.. we did a frequency check with generator and at 45hz it is unbelievably strong and full of “guts” and then goes upto 6000hz with ease (that is the top limit if the we555).
These solid wood babies play better than the plywood we15a or metal 16a (I have both…) as they are so solid and do not vibrate. This enables better control of the lower frequencies and dynamics are not reduced because of materials….
Been asked so many times now who made these horns…..yes it’s me with knowledge, skill, patience and most of all passion…..some have asked if I can make for them….depends…!
All fun….
13Audio 
Yeah with a 13A you don’t need a 12A at all….if your listening position is on the ceiling!
In an average setup with the 12A above the 13A, all of the highs that are reaching the listening chair, presumably set upon the floor, will be from the 12A due to the directionality of the HF output.
As you note, there is no crossover filter. The 13A is set 3dB higher than the 12A with the autoformer and set a few feet forward of the vertical plane of the 12As to account for longer path length. The effect of the 12/13 combination is a bigger, more powerful sound rather than a wider range sound.
Joe,
Good to read you. No doubt 7 metre high ceiling configurations could call for hanging the 12’s above the 13’s. No I don’t cling to the ceiling like Spider-Man….as you know when you incline up or down the 13a the highs are affected, lower and you get more higher and less. This acts like the physical low pass filter on the 15 or 16 killing the higher frequencies that do have some distortion….
Here we are putting unreal speakers in real places….
The other unanswered question is the relative HF output of the 12A and 13A. It seems to me that the complicated path of the 13A would roll off more HF output than the 12A, aside from any questions of listening position,
And on that note, in a seated position in front of the 13A, one would be well outside the beamwidth of the horn, which probably peaks about 35 deg in front of the central axis of the horn mouth (if it follows the pattern of 12A and 15A “snail horns).”
It would be nice to have reliable polar measurements of the 12A and 13A, but working from general principles it appears that only Spiderman could experience the sweet spot of a 13A in a domestic setting. People planning to go with stand-alone 13As are well advised to budget for nice silk webs on the ceiling or have a balcony in their house.
I actually have an atrium with a balcony of sorts in my living room, but, alas, no 13As!.
Hey joe,
You would need the Spider-Man outfit also….
I use the we597a cut at ? 2mfd works well.
When I lower the horn so the mouth is pointing towards me it kind of get harsh up top.
With a friend we did some listening raising it more and more then lowering the 597a at same time.
No idea if I could be able to do all the measurments. The relations I have in Japan with persons who use like me these big horns all day everyday actually advise to have the 13a pointing upwards far more than I do. Anyway I will be playing with this “home made baby” for a while. I will be installing the second one in the near future just to see how that sounds…
All fun and see you in Munich?
I have the Spiderman outfit. I’m wearing it right now, in fact. My usual Tuesday garb…
We will be in Munich with an original stereo set of WE12A/13A, which is about as out of context as it is possible to get at a high end show.
One reason for the reported harshness of the 13A more on axis could be the convoluted path. I don’t know anybody who measured to see what is coming out of that horn. It might only go out to 4k…who knows?
I never sat down and analyzed a 13A without 12As.The 12A is not harsh and sounds best/most balanced right in line with the HF lobe.
I’d hesitate to think these horns are interchangeable, rather they are two parts of a system and the 13As look like the “add-on” extra section of the setup.
Joe,
Well i can make a pair of we12a just it try it out? Maybe I am mad enough to do that? The other pair of 12a’s have found there new home….
To claim that a 12A is a tweeter horn and a 13A, a woofer always seemed a really unthoughtful idea to me. All you have to do is look and not even very carefully…..
Whoa…your 13A is indeed pointing really low! Your Japanese friends might be correct but you can only know by experimentation. Many WE maniacs would never change anything WE did, even if it makes good practical sense to do so.
Joe,
Yeap…
Sitting position is low also. Maybe you will experience one day….
Still….feel very fortunate to play with these babies…
All fun.
Tim