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SQ8 CV / Gate SequencerInputs: Outputs: Power: Controls: Indicators: Size: |
Introduction
Analogue sequencers allow you to programme a set of voltages and Trigger events (8 in this case), and allow you to step through them by using a clock signal or LFO square wave. With each step, then next voltage as set by the contol is present at the CV output. This way repeating melodic lines can be produces. The sequencer need not control pitch, it could be used to change the filter cut-off, volume, or LFO speed.
The advantage analogue sequencers have over hardware sequencers is firstly their immediacy. Having all the controls, switches and sockets in front of you allows quicker programming. Secondly, as the output is an analogue control voltage and not a digital MIDI signal, the output of analogue sequencers can easly be mixed with other voltages, or processed in some way.
The SQ8 is a single channel sequencer with 8 steps. As it is single channel, larger sequencing systems can be built up by doubling up on sequencers. As they are all separate, you can clock them at different speeds or clock divide ratios.
When used with our master clock module MC01 all sequencers can be reset globally from the Master Clock and they will be reset to THE LAST STEP. With just about all other sequencers, especially when using MIDI as the master clock, the sequencer must manually be stepped to the last step, otherwise when the clock is started, step 2 is in fact the first step triggered. Our automatically go to the last step eliminating this problem (see note in MC01 section for more explanation).
Controls In Detail
Controls In Detail – standard operation
Clock In
The SQ8 requires a +5V clock signal. Each clock signal will advance the sequencer 1 step. When the last step is reached, it resets back to the first step. Take the clock signal from a square wave LFO, Clock module or MIDI to Clock converter.
Clock Thru
The clock signal appearing at the CLOCK IN socket is buffered and transferred to the CLOCK THRU socket, so it can be daisy chained to another sequencer.
Reset In
A 5V signal in here will reset the sequencer to step 1.
Step 1 Out
Each time step one is played, the step 1 gate socket will go high (output +5V). This socket can be used to trigger other devices, such as a cymbal sound at the start of each bar, or to trigger another sequencer. It can also be used to allow the FS01 fill in module to count bars. The step 1 out will give a clock signal that is the main clock in divided by out.
CV Out
This socket will output a control voltage set by the pot for the current step. It can be changed in real time.
Gate Out
This socket will output a 5V gate signal at each step where the CV control is not at the zero position (i.e. Gate ‘on’).
Step Button
This allows the sequencer to be manually stepped by one step at a time whilst the clock is not running. It can also be used to reset the sequence. As with most analogue sequencers, step it to the last step (8 or whatever is patched) so that when you start the clock, the sequencer starts on position 1.
Note: The step button will only work when any clock input signal is at a low state (0V). So it will note work when the clock input is high. This situation will note arise in normal use, as one would only normally use the step button when the master clock is stopped (making the clock signal low). If the sequencer is being clocked by a clock divider, even when the clock is stopped, it is possible that the clock signal may still be high until reseted.
CV / Gate pots / Range switch
The CV and Gate functions are built into a single combined pot/switch. Turning the pot fully left will turn the Gate off. You will fell the switch click off.
There are 8 CV pots, 1 for each step. When the range switch is HI the range is approximately 0 to 10V, when LO the range is approximately 0-5V. LO is best for use when controlling a VCO as this gives better abillity to fine tune each step.
The CV pots have a built in Gate switch. Pull the knob out to turn off the gate, push it in to turn it on.
LED Indicators
There are 8 LED’s. These will light in turn to show step position.
Alternative Applications Of Controls:
Clock In
The sequencer does not have to be stepped through at normal regular intervals as is usual. It can be clocked from any source, such as the gate from a MIDI-CV converter or monosynth, the trigger out of a drum machine such as the TR606/808, or from the gate outputs of other analogue sequencers. This allows it to step through the sequencer rhythmically, as and when you want.
If a sine, triangle or sawtooth wave (that goes positive and negative in polarity) is used, the sequencer will step randomly (backwards and forwards), and also skip beats! This can produce interesting musical results or is good for sound effects.
Reset In
It can be taken from an source, such as Gates from MIDI to CV converters, synth’s or other analogue sequencers.
Step Out
It can be used individually to clock other analogue sequencers, to trigger analogue percussion modules, gate monosynths, or control analogue switching modules such as our fill-in module FS01.
The step out is basically a divide by 8 clock divide (relative to the clock input signal). Any step output (normally step one) can be used to clock something else 8x slower.
CV Out
If a very high frequency clock pulse is used to step the sequencer (in audio frequencies), the CV pots can be used as a waveform generator. Because of the quantised steps, it will sound digital in form, unless an external slew rate generator (portamento) module is used to smooth the waveform.
More SQ8 Example Patching
Standard connection to a monosynth to control pitch and gate;
CV out to Synth CV in.
Clock Thru to Synth Gate in.
Filter control of monosynth;
CV out to Filter cut-off input.
Connect CV and Gate of synth to another sequencer or MIDI to CV converter.
Alternative connections to a monosynth;
Plug CV out to Synth CV in
Step 1 out to Gate in
The synth will be triggered on the 1st step. If the release time is long, you can still hear the pitch changing with each step, but without the EG re-triggering.
Miscellaneous Connections;
Step 1out is a divide by 8 clock divider.
Take step 1into the clock of another sequencer.
Use a quantiser if you want to precisely control to pitch of a synth.
Use a voltage scaler to scale down the control voltage to a smaller range when necessary.
When using a clock other than our MC01 master clock module, (as with all analogue sequencers), you must manually step to the last step of the sequence before you start the clock. This is done automatically when using the MC01.
To control transpose:
Use 2 SQ8s (we’ll call them A and B) and a mixer.
Clock the SQ8 A 1 step every bar. Clock SQ8 B as normal. Feed the output CVs of both through a mixer (like the MX61), then take the output of the mixer to a synth as normal. SQ8 A will control the transpose level, changing every bar. SQ8 B sets the pattern of notes as normal. This is a handy and easy way of shifting the pitch of all 8 steps up or down with only one pot.
Using the SQ8 as a waveform generator
By clocking the SQ8 at audio frequencies, the output of the sequencer can be used to generate audio waveforms.
The simplest example is to create a square wave. Simply set to 1st 4 pots to full and the following 4 to zero. To double the frequency, set the 1st two pots to full, the next two to zero, and repeat.
Now take the 1st example with 4 pots at full and 4 at zero. Now if you start to change the the levels away from their setings, you will hear the timbre change. All combinations of settings are useable, so just play around live as the sequencer plays.
Concussor
Modular Synthesizer from Analogue Solutions
Tel:+44 1384 35 36 94 Fax:+44 1384 35 36 94
e&oe (c) 9 2002
