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"Junost' - 21 is a portable polyphonic keyboard EMI. A player can hang it on a shoulder. Timbre of sound can be changed in accordance with players desire by the use of controls or choosing one or 12 programed timbres with digital indication of chosen one.

The instrument changes sounding during playing composition using such effects as chorus, unison, transposition with continuous and coarse control, frequency and timbre vibrato with continuous frequency, depth and delay time control, fixed and dynamic change of timbre, attack and fading of sound. Attack, fading and level of envelope of the filter. Filter's cutoff frequency control from the keyboard.
The case of the instrument is made out of aluminium. Control panels are made out of shockproof polystyrene. Power unit is made as an individual part.

Specifications:
— Formation of envelope in volume with attack and fading duration control.
— Formation of envelope in timbre with attack duration control, fading, level and depth of timbre control.
— Frequency and timbre vibrato in depth, frequency, pre- delay control.
— Transposing on an octave (continuous and coarse)
— Tuning of the musical range.
— There is a filter with continuous range, depth and sharpness control.
— Possibility to control cutoff frequency of filter by the keyboard.
— Fixed choice of chorus and unison sounding.
— Number of octaves in a keyboard (from "F" to "E"), 4
— In audible range, 6
— Number of programmed timbres, 12
—Power consumption max, 11V*A
— Dimensions, 85x260x860 mm
— Weight with power supply, 7 kg (approx. 14 lbs)
— Amplitude output max 2,4 V
— Signal/(Backgound+noise) in a pause max 55dB
— Relative frequency instability of leading generator over 4 hours of working max 0,3 %"
Panel translation below.