Earthworks PM40T User Manual - page 6
The PianoMic™ System provides the following benefits:
• Excellent overall piano sound with uniform level from all strings
• Superb sound with the piano lid up or down
• Tremendous gain before feedback
• Minimal leakage from other instruments surrounding the piano
(with piano lid closed)
• Microphones are not visible from outside the piano
People are astonished when they hear the exceptional sound quality of
the PianoMic™ System with the piano lid closed. Conventional microphones
perform poorly in a piano as the sound inside the piano is coming from every
direction and from multiple sound sources. Every string is a sound source. The
soundboard is a large and complex sound source. In addition, sounds are re-
flected off the piano sides, the soundboard and the piano lid multiple times with
little attenuation. Sounds inside a piano are randomly arriving from every pos-
sible direction at similar levels, all at the same time. This is a classic example of
a “diffuse sound field” which is defined as a confined area where there are multiple
sound sources and multiple reflections arriving at the microphone from every an-
gle at similar levels simultaneously. A microphone that is placed in such a diffuse
sound field has to pickup all of the sound with a proper tonal balance. For optimum
results, this task requires a High Definition Random-Incidence Microphone.
Conventional microphones
are “Free Field” micro-
phones, and regardless
of their pickup pattern are
designed to only pick up
sounds accurately in front
of the microphone (See
Figure 2).
Random-incidence micro-
phones are designed to
uniformly pick up sounds
arriving simultaneously
from all angles and direc-
tions, rather than to the
sound coming only from
a primary source that is in
front of the microphone.
Random-incidence micro-
phones have exceptional ac-
curacy and tonal balance in
a diffuse sound field, where
sound arrives from all direc-
tions randomly and simulta-
neously (See Figure 3).
4
Figure 3. Random Incidence Microphones inside a piano pick
up sound accurately from all directions
Figure 2. Conventional “Free Field” Microphones inside a piano
only pick up sound accurately in front of the microphone
9
Leather Pouch Attached to Piano Leg
The enclosed leather pouch has Velcro straps that allow it to be attached to the leg
of a piano. The pouch is open at the top and the bottom has a strap to prevent the
electronics box from falling out of the bottom. There is an opening at the bottom
of the pouch to conveniently attach the two standard XLR-3 microphone cables
that go to your mixer preamp inputs (See Figures 15 and 16).
Figure 17.
Mounting Electronics Box
on a Microphone Stand
Electronics Box Attached to Mic Stand Bracket
The electronics box has a threaded insert in the bottom of the box that will
mate with the threads on a standard microphone stand. By this method, the
electronics box can be mounted to a short mic stand to keep it above floor level,
if desired (see Figure 17).
Figures 15. Placing the Electronics Box
in the Pouch.
Figures 16. Attaching the Pouch
to the Piano Leg.
Leather Bag