Tuesday, May 30, 2006

Fisher double wide version and power supply - world's first phantom powered ribbon mics


Shown here is the double version. I haven't seen the inside of this one yet. This has to be one of the rarest production ribbon mics - not something you would read about in ribbon microphone reviews!

5:03pm: Micha informs me that the ribbon is not double width, but it is a two ribbon arrangement, sandwiched for higher output. This is interesting since we just isolated the ribbon motor on the single ribbon mic, below, connected it with a Crowley and Tripp ribbon microphone transformer, and it produced a very healthy output! Also, the response of the mic is pretty similar without the amplifier, so that amp is fairly flat.

Actually, RCA labs and Harry Olsen made a number of amplified ribbon microphones almost as soon as the first ribbon mics were made, in the 1930s. These amplified ribbon microphones used multiple tubes located in the housing, which was quite large by today's standards.

3 comments:

Anonymous said...

isn't this really a phantom powered ribbon mic from the 60's or am I missing something????.....

JY

Bob Crowley said...

Yes I would say so. And it is not the first by any means. Harry Olsen describes an amplified ribbon mic in his book "Acoustical Engineering" from the 1950's.

Peter S said...

I seem to be making serial posts. Charlie made this pair specifically for me at my request, and they may be the only instances of this design he made. At the time, I was recording some very soft instruments and was looking to reduce the noise a couple of db. His mics weren't noisy, but without the typical condenser peaks to make instruments brighter, noise was somewhat more apparent in quiet locations. This design maintains field strength while reducing electrical resistance in the ribbons, and it is slightly quieter. Because the hinges are at the center of gravity, he suspension worked very well, though the mics were heavy enough to make location recording somewhat precarious. They were/are beautiful sounding microphones. It is gratifying to see them still being used. It was important that they go to someone who would appreciate them. I would check the capacitors in the amps. Almost everything I have of that vintage has needed them replaced.