The horn-violin (or trumpet-viloin) is a wierd old instrument. Best of my knowledge this is an american instrument but there are some who believe that is a British invention. Maybe both statements are true.
It is certain that the instrument is as old as the gramophone. As shown in the picture, there is no body of this violin - a gramophone membrane generates the sound. You play on this violin as a normal violin. The difference is that the horn-violins sound is not pure but "crepitate." As if you were listening to a gamophone.
So at this violin not the instrument maker's skill or expertise is the important thing, but the membrane. If the membran is an original gramophone membrane, it sounds good. If you have any other membrane, the sound is miserable.
The horn-violin's (or trumpet-violin’s) price basically depends of the type of the membrane.
My horn-violin is a new instrument with an old gramophone membrane. A young master created it with meticulous care for his examinations. You can see this in the scroll and the neck
and the quality of accessories. The end button is my favorite.
I have ordered a hard case for the instrument but it looked like a baby's coffin. It was safe but it was morbid to use - it is no longer in my possession. Until there is a better idea, it will hang on the wall.