Western Electric Plans.

simonms

Member
2010-04-06 6:35 pm
Ok, this seems to be something of a stab in the dark, granted.

I have been looking for plans for a 12a horn for years, the likely sources are disinclined the help at all, seem like some sort of mafia to me.

I don't want to copy the actual horn itself as this sort of project seems to offer no real progression in terms of imagination so what i need is the cross sectional curve through the path of the horn i.e the curve that the horn is constructed around.

If anybody out there can assist in any way or point me towards possible sources for such a thing i would be tremendously grateful.

I think this sort of thing should really be accessible to like minded and capable people rather than hidden away and protected so any other WE plans that might exist for the 15a 16a or 22a for example please post, i am sure many would find such things of great interest.

Best wishes,

Simon.
 
I have been looking for plans for a 12a horn for years, the likely sources are disinclined the help at all, seem like some sort of mafia to me.

I don't want to copy the actual horn itself as this sort of project seems to offer no real progression in terms of imagination so what i need is the cross sectional curve through the path of the horn i.e the curve that the horn is constructed around.
Simon,

The exponential curve of the Western Electric 12a (or any other WE horn) can be duplicated by measuring cross sectional points from the curved center line at regular intervals of the side view, then scaling them up to the actual size of a 45" x 45" mouth, with an 11' path length. The expansion appears symmetrical, but curved in the (usual) vertical plane. I don't recall offhand the throat dimension of the 22A "reciever" (driver) but that should be easy to find.

You could also input those dimensions in David McBeans free Hornresp program, and select "exp" and it will show the same expansion in a straight horn, with a diagram.

Happy horning!
Art
 

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simonms

Member
2010-04-06 6:35 pm
Thanks for the reply,

The dims seem to differ on the 12a drawings on the web mainly on the height which is given at 62.5" in some and 67.5 in others. I have got all the info on the expansion it's just the curve i am interested in. It does seem however that adopting you method results in the probability that the height should be around 62.5" given the path length and other dimensional considerations.

I have been told by people who actually have plans that all the drawing on the web are not to be considered as accurate as WE didn't want their designs to be copied, whether there is any truth in that i don't know.

I have been in contact with a member here who is helping me out so that's a huge step forward in varifying the dims.
 
I have been told by people who actually have plans that all the drawing on the web are not to be considered as accurate as WE didn't want their designs to be copied, whether there is any truth in that i don't know.
Simon,

The WE drawings look very much like photographs of the actual horns. Any minor differences would result in minor audible changes. Considering the ragged frequency and polar response that these horns have, not much to worry about, unless you were trying to make a match for an existing unit- in which case you could measure and duplicate it, assuming you could procure the same materials it was made from.

Since there is no internal bracing in these horns, the materials used for construction will make a large difference in the response, regardless if the original contours are followed exactly.

Art
 

turk 182

Member
2012-10-26 3:03 pm
i'm not sure what the romance or attraction to these is other then the kitsch factor. after a lot of blood, sweat and labour removing a 16a from an old theatre in my hometown a lot of time was wasted in trying to coax them into sounding good(several drivers and eq schemes and a lot of effort trying to inert them) they eventually where cut up and sold as scrap by the building owner.
there's no magic to these as far as i know.
 

POOH

Member
2010-10-05 9:06 pm
Ohio
Blasphemy! :eek: :)

http://www.lencoheaven.net/forum/index.php?topic=7616.0

i'm not sure what the romance or attraction to these is other then the kitsch factor. after a lot of blood, sweat and labour removing a 16a from an old theatre in my hometown a lot of time was wasted in trying to coax them into sounding good(several drivers and eq schemes and a lot of effort trying to inert them) they eventually where cut up and sold as scrap by the building owner.
there's no magic to these as far as i know.