headway EDB-2 VAP - Transducers and Contact Pickups

vi) Transducers or contact pickups - high Impedance ( e.g.
Headway Passive Contact Pickup ) Headway - PCP-2 or PCP-3,
pictured above. These should be less prone to feedback than
microphones 5-10 megohms MΩ optimum
vii) Passive piezo ceramic - Under saddle fitting - high
impedance 5-10 megohms MΩ optimum
viii) Passive flexible “piezo film” contact pickups or under
saddle transducer ( may be encased in rigid metal ) - Ultra high
impedance. 10-20 megohms MΩ optimum
ix) Passive Magnetic Sound-hole Pickups - Low to mid
impedance normally fairly proof against feedback. A traditional
mellow sound might be optimum at about 800 Ohms to 1 megohm.
However a brighter sound may be preferable. This is optimum at
about 5-8 megohms MΩ optimum
x) Silicone condenser microphones or MEMS include analogue
output miniature microphones often incorporated in digital devices.
Not unrelated to electret condenser mics they exhibit a superior
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