by Joe_DS »
Tue Jul 18, 2006 8:42 pm
Hi Ian:
I'm not the O.P., but I've always been curious about the Columbia Viva-Tonal gramophones.
Did the 117 incorporate "Plano-Reflex" (SP?) technology, or was a conventional exponential type tone arm and sound chamber used?
In know that Columbia sort of went their own way for the design of the acoustic post-1925 gramophones--both in the UK and in the United States. For instance, the US-produced Viva Tonal phonographs did not incorporate the (multi-passage) folded exponential style horns designed by Western Electric for Victor Orthophonic models. Even the large 800-series machines were equipped with substantially different tone chambers.
SEE:
http://www.intertique.com/VivaTonalNoBack.html
I've also seen illustrations of the metal horns used in some of the UK models, which seem to be a rather simple design, in which the tone chamber divides into two sections which come together at the horn's mouth. (I've yet to spot a photo of this on the web.)
The Plano-Reflex models I've seen have flattened surfaces throughout the tone chamber--points at which the sound waves are "reflected." I've never seen one in person, so I haven't a clue as to what these would sound like.