Meridian Arts Ensemble
consists of brass instruments and a drum set.
A lot of their work is done in the style of rock and grunge. The brass instruments have microphone in
their bells and some of the pieces use effects pedals to distort the
instruments. This group commissions a
lot of new works and I am particularly intrigued by this type of work.
Gaudete Brass, performed
a work by Ravel using brass instruments and theremin. The concept is to take old ideas and adapt
them for a new ensemble. This inspired
me to look into how the theremin works and I will post what I found from Wikipedia
at the end of this post. I never knew
what the theremin was until my post tonal analysis class. We listened to a performance done in the 1930’s
of a theremin performing classical music, which is what this group is about.
New Brass Directions is a
large brass groups that plays nearly every genre of music. Their goal is to continue changing the
accessibility of brass music and bring it to a larger, more diverse audience.
TILT Brass Ensemble is a
contemporary brass group who shares the common goal of exploring new genres and
providing new music for brass ensemble.
There are many ways we
can help to advance brass music and go in new directions. Ideas of experimenting with new
instrumentation, new genres and new composers are all great ideas. Rather you are commissioning a work,
composing one yourself or finding an old piece to adapt to a different group,
all ideas help to further the cause. I
am a firm believer in bringing music to new audiences. We need to strive to perform in less than
common venues and draw diverse crowds. I
feel we owe it to ourselves and the public to not limit ourselves to playing
recitals in concert halls.
I was not a particular
fan of the John Cage festival that was done at the UCC, but I am a fan of what
was attempted to be accomplished. It’s
possible there were people there that have never heard a symphony band or a
bassoon before in their lives.
Hopefully, it inspired someone to attend a recital or watch a youtube
video they previously would not have.
The theremin is almost
unique among musical instruments in that it is played without physical contact.
The musician stands in front of the instrument and moves his or her hands in
the proximity of two metal antennas. The distance from one antenna determines
frequency (pitch), and the distance from the other controls amplitude (volume).
Most frequently, the right hand controls the pitch and the left controls the
volume, although some performers reverse this arrangement. Some low-cost
theremins use a conventional, knob operated volume control and have only the
pitch antenna. While commonly called antennas, they are not used for receiving
or broadcasting radio frequency, but act as plates in a capacitor.
The theremin uses the
heterodyne principle to generate an audio signal. The instrument's pitch
circuitry includes two radio frequency oscillators. One oscillator operates at
a fixed frequency. The frequency of the other oscillator is controlled by the
performer's distance from the pitch control antenna. The performer's hand acts
as the grounded plate (the performer's body being the connection to ground) of
a variable capacitor in an L-C (inductance-capacitance) circuit, which is part
of the oscillator and determines its frequency. (Although the capacitance
between the performer and the instrument is on the order of picofarads or even
hundreds of femtofarads, the circuit design gives a useful frequency shift.)
The difference between the frequencies of the two oscillators at each moment
allows the creation of a difference tone in the audio frequency range,
resulting in audio signals that are amplified and sent to a loudspeaker.
To control volume, the
performer's other hand acts as the grounded plate of another variable
capacitor. In this case, the capacitor detunes another oscillator; that
detuning is processed to change the attenuation in the amplifier circuit. The
distance between the performer's hand and the volume control antenna determines
the capacitance, which regulates the theremin's volume.
Modern circuit designs
often simplify this circuit and avoid the complexity of two heterodyne
oscillators by having a single pitch oscillator, akin to the original
theremin's volume circuit. This approach is usually less stable and cannot
generate the low frequencies that a heterodyne oscillator can. Better designs
(e.g. Moog, Theremax) may use two pairs of heterodyne oscillators, for both
pitch and volume.
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