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Theremins begin with the
basic sine wave, this sounds more whistle
like.
or mellow with RS Illusion character.
tw-2.mp3
Pot 1 gain set to just below peak clipping
TW-2 connection - smoother & "CC"
Pot 2 set properly for green display
Pot 3 fully counterclockwise
LED 2 is off, Pot 2 set at the audio out mic. level.
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Noise is added to
the peaks to break away from the whistle. Generated from the
TLC555 chip.
tw2-bitofpot3ledoff.mp3
bit of reverb
Pot 1 gain 1 set to just below clipping
TW-2 connection smoother & "CC"
Pot 2 audio out set properly for green display
Pot 3 timbre adds the noise to the top of
peaks
LED 2 is off, Pot 2 set at the audio out mic. level.
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Same as
above except the microphone input to the computer is
slightly overdriven by Pot 2 audio out which turns the display red!
The red does come on a little early when the level is still
good.
I am not a
musician but what does the to much red overdrive sound like?
Buzzy low end.
TwoOctaveRainbw.mp3
Ok, ok so I only
know one tune, sort of? lol
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Microphone input to
the computer is to low, the dim green indicates the audio out Pot 2 needs to be turned up a bit more.
tw-1.mp3
Pot 1 gain 1 set to just below clipping
TW-1 connection for sharper/piercing sound
& "CC"
Pot 2 audio out set to low dims green display
Pot 3 timbre is fully counterclockwise, no noise.
LED 2 is off Pot 2, set at the audio out mic. level.
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Pot 1 gain 1 set high flattens both peaks
TW-2 connection smoother & "CC"
Pot 2 audio set properly for green display
Pot 3 timbre adds noise to the top peak
LED 2 is off, Pot 2 set at the audio out mic. level.
tw2-bitofpot3ledoff-odpot1.mp3
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Diagnose
your problems in steps:
Use your AM Radio to diagnose & listen to many of your theremin problems.
I followed these steps to isolate the cause of this low frequency
unsteadiness in the low pitch.
low-unsteadiness.mp3
* Removed both IC's (7555, TL082) Did disabling circuits
solved problem? No
* Disconnected the clip connection to the Lev Antenna spring.
Spring vibration? No
* Unsteadiness is still heard over the AM Radio which
indicates it is originating at the oscillators.
* Disconnected the TW-2 connection. Bingo! My first TW
diode was improperly applied. Fixed
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Note: Pot 1 turned almost
off might attenuate the higher frequencies.
Noise or hissing is
a desired effect introduced by the TLC555 when LED 1 is on;
which is also the Null Point indicating LED.
Normally you would want the hissing/noise LED 1 to be adjusted
by Pot 1 as always on or always off during the full range of a
song. Pot 1 set to low could drop out the noise effect during a
song at higher frequencies.
Keep Pot 1 turned down so LED 1 never lights if you want the
cleanest
sound.
Pot 2 audio out using the CdS volume control will light the LED 2
which driven at different intensities will enhance the sound in
different ways.
If you switch LED 2 on or off at a line level output on the
Audio Out it has nice interesting effect
on the sound. The switch pads are normally connected together on
the copper clad side of the board, drill them apart if you add a
switch.
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| Limited
by what parts I could find at Radio Shack my bread boarding
evolved into a remarkable theremin!
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