STT-1
(21) RATIO CONTROL "RATIO"
Conductive plastic rotary potentiometer offering continuously variable compression ratio.
When fully CCW, the lowest and most gentle compression ratio is achieved (1.4:1). When fully
CW, the highest and most pronounced compression ratio is achieved (30:1). A compression
ratio of approximately 10:1 or higher is typically called "limiting" hence the STT-1 dynamics
section is properly called a "compressor/limiter."
(22) PRE / POST DYNAMICS SELECT SWITCH "FLIP DYNAMICS"
Pushbutton switch which determines the order in which the dynamics section is placed in the
audio signal path. When switch is depressed and LED is illuminated, the dynamics section
precedes the EQ section. When switch is not depressed, the dynamics section follows the EQ
section. Use this switch to achieve desired sonic objectives. In some cases, compressing equal-
ized program can offer an "effect" not achievable with pre-EQ compression. When the Equalizer
is not enabled (EQ IN switch is disabled), pre/post selection is also disabled.
(23) DE-ESSER SELECT ROTARY SWITCH "DE-ESSER"
Rotary switch which selects the notching frequency of an opto-electronic de-esser. De-esser
provides selective filtering of particularly "sibilant" frequencies, such as found on overly breathy
singers, RF "hissing" artifacts encountered with certain wireless mic receivers during dropout,
and so forth. Compressor/limiter "dynamics" switch (#24) must be active to achieve de-essing
function.
Origin's de-essing function employs the same opto-resistive gain reduction elements used by
the broadband compressor/limiter. The de-essing function can be used simultaneously with the
parametric equalizer (pre or post), and can be used with the additional solid-state audio path
amplifier, vacuum tube audio path amplifier, or with no additional amplifier in the audio path.
The de-esser and broadband compressor/limiter cannot be used simultaneously.
When the “Comp/Lim In” switch (#24) is active and illuminated, and the de-essing rotary
switch is fully counter-clockwise, the broadband compressor/limiter is active and the de-essing
function is off. As the de-essing switch is rotated clockwise, the broadband compressor/limiter
is disabled and the de-esser becomes active at the center frequency noted on switch. When any
de-essing frequency is selected, the meter Gain Reduction function is disabled.
The de-esser works in conjunction with the compressor/limiter’s dynamics controls (threshold,
attack, release, ratio) and signal input level. At lower input, threshold, and ratio levels, the de-
essing function is less prominent. At higher levels, de-essing becomes more pronounced. The
de-esser in the Origin is intended for modest de-essing duties. For more aggressive sibilance, a
dedicated de-essing unit with greater flexibility is suggested.
At low settings (fully CCW) of threshold and ratio, the de-esser function is essentially off. For
instance, at 1.4:1 ratio, the de-essing notch is very broad with minimal cut. As the ratio and
threshold controls are increased clockwise, the de-essing notch becomes more pronounced
with an apparent tighter “Q”. It is recommended that the fastest attack and release be used as a
starting point; the user should then experiment with different settings of attack and release to
achieve optimal de-essing performance. The Origin de-esser has also been found effective on RF
microphone "envelope hiss," guitar fret squeek noise, and such.
