The Talking Machine Forum — For All Antique Phonographs & Recordings

I have a book from the 1930s called the "process of sound reproduction" basically it is a book on gramophones and how different horn shapes effect the sound it is only 27 pages long and I read a small section and it talked about having a reflector in the middle of an exponential horn no more than ⅛ the size of the horn in the centre made from 2 pieces of thin wood and to have the wood together forming a point at 40 degrees to each other with the opening facing into the horn so I have planned to create this design with balsa wood and fix it to the side of an exponential horn I have made a very basic diagram so you hopefully know what I am saying - http://fs5.directupload.net/images/161124/fqqqdhkt.jpg all I want to know is would this have any effect on the sound quality or tone?

Since there don't seem to be any period horns with this attachment, it apparently was not an idea that had any basis... but who knows? I have an Aerenola phonograph that has a tonearm which reflects sound back into the horn which then directs it forward, but I don't know if your article is suggesting the same principle. The big question is how would you attach this device in the center of the horn opening and is its purpose to act like a mute on a brass instrument or what is it supposed to do?

It says it is suppose to remove any 'tinny' qualities and give a more 'full' sound. And it would be fixed via glue.

Thanks, Jake

It might give a reverb sound by reflecting the sound back into the horn... who knows?

I'll report back tomorrow I shall try it!

Well to my suprise it actually worked i did try it with a very cheap thin steel horn so I think all it really did was remove the vibrations from within the steel by sending them into the balsa wood so I would advise this to anyone with a very thin metal horn as it does give a less harsh sound than original however it hardly compares with my HMV re-entrant!

Thanks, Jake

The Cliftophone (the brand that patented a horizontal soundbox, with the diaphragm facing the disc) has a horn with a small reflector in its mouth, but it is metallic, not wood. I have one of those, but I cannot discern any special sound, either from the horizontal soundbox or from the horn with a reflector.

As I say for me it slightly removed any "tinny" sound but I think that may have been due to it reducing the vibrations within the metal of the horn itself as it is extremely thin.

Thanks, Jake

"...there don't seem to be any period horns with this attachment..."

Isn't that just what this is?????

No, Jerry. That's the opposite, in some sense, as it takes care of the exponential envelope of the horn. The proposed attachment is instead an empty cone, which will chop the horn's envelope (whichever it was), and has absolutely no rationality. It will destroy the bass response in first place, and have little to no effect on trebles aside from lowering the overall volume (which may give the wrong feeling that the trebles are better controlled).