ANALOGUE SYSTEMS RS340 User manual

A N A LOG U E S Y S T EMS R S-I N T EG R A T O R 115
R S 340
GA T E D E L A Y
INTRODUCTION
There areoccasions on which you may want togenerate a Gate or Trigger atsome
specified time after a sonic event occurs.
This,for example,allowsyou touse twoVCO / VCF / VCA signalpaths-oneslightly
delayed with respect to the other - to create a single, composite sound each time
thatyou press a key. You could use one VCO / VCF / VCA path to place a "chiff" at
the start of a flute or woodwind note, and the second to generate a sustained
sound that imitates the body of the real instrument. Alternatively, you can use
this technique to create interesting rhythmic structures in which one percussive
sound isfollowed closely by another.
The problemsencountered with triggeringmultiplesounds in thiswayare twofold.
Firstly, you will often wish to initiate the secondenvelope very soon after the first
-more quickly than is possible using your hands. Secondly (and even ifthe delay
between the two Gates is long enough for you to initiate both manually) there's
the problem of consistency: the relationship between the two parts of the sound
mustbe the same for each note you play.
Tosolve these problems there'sa dedicated module thatwillcreate the appropriate
delayed Gates and Triggers for you. It's a Gate Delay.
IN USE
The RS340 is a multi-mode Gate Delay module and Shaper that recognises any
positive-going pulse exceeding +1V, and then generates a Trigger and a Gate of
specified duration a user-defined timeafterwards.Two LEDsoffer visual feedback
regarding the Gate status of the module.
GATE IN
This accepts a positive-going pulse in the range +1V to +20V to initiate the Gate Delay cycle.
DELAY TIME
This determinesthe length of time between receipt of the input pulse, andthe output Gate and Trigger.
The minimum delay is 10mS. The maximum is 10S.
GATE TIME
The GATE TIME allowsyou todeterminetheduration of thegeneratedGatepulse.Theminimumduration
is 10mS. The maximum is 10S.

116 A N A LOG U E S Y S T EMS R S-I N T EG R A T O R
Status LEDs
Two LEDs give a visual indication of the state of the RS340 at any moment.
• The Green LED will be litduring the delay period.
• The Red LED will be litwhile the delayed Gate is "high".
TRIG OUT
This outputs a +10V pulse of duration 10mS.
GATE OUT
This outputs a +10V pulse whose duration isdetermined by the GATE TIME control.

A N A LOG U E S Y S T EMS R S-I N T EG R A T O R 117
RESET IN
The RESET INacceptsa positive-going pulse in the range +1Vto+20Vto resetthe Gate Delaycycle. This
terminates the current Delay or Gate (dependingupon where the module isin the cycle) andreturns to
"wait" for the next input pulse.
RETRIG/ NON-RETRIG
The RS340 offers two modesof operation:
• NON-RETRIG
Provided that no RESET pulse is received, the module always completes the full Gate
Delay cycle, regardlessof any further inputs at the GATE IN socket.
• RETRIG
The module terminates the existing cycle, resets, and starts a new cycle whenever a
pulse is received at the GATE IN socket.
The Gate Delay used as a pulse shaper
Because a Gate Delay responds to brief incoming pulses and creates Triggers and extended Gates from
them, you can also use it to derive high quality Gates from poor gate signals such as the outputs from
envelope followers, and click tracks replayed from tape. This is useful when you want to reshape an
audiopulseintoa form that thesynthesiser canuse for timingor triggeringpurposes.For moreinformation
on this subject, you should also refer to the chapter on the RS50 Shaper / Trigger / DC Shifter module.
Furthermore, you can use a Gate Delay to generate an extended but largely undelayed (i.e. only by
10mS) Gate whenever you present it with a Trigger or an audio click. You can use the output as a
conventional Gate or as an extended Trigger. The latter will guard against false triggers caused by the
abrupt end of an input click.