The instrument
The Acousticel Crystal Microphone is an accessory for Brush Soundmirror Recorder. 40-6000Hz. He has an aluminium case and stand.
The Brush Development Company was the inventor of the Bimorph piezoelectric crystal unit.
The Acousticel Crystal Microphone is an accessory for Brush Soundmirror Recorder. 40-6000Hz. He has an aluminium case and stand.
The Brush Development Company was the inventor of the Bimorph piezoelectric crystal unit.