In earlier analogue systems the Sample and Hold (S&H) was considered a very powerful module. It enables the system to generate tunes and riffs and creates all sorts of interesting modulations on controlsignals. The S&H module has two inputs and one output. At the red input samples a signal at the moment it's being triggered by the yellow input and stays at the output until the next trigger arrives. (Triggering occurs when the signal at the yellow input shifts from any negative or zero level to a level greater than zero - Manual V3.0 page 157)

Let's look at some examples.

S&H for random pitch modulation:

The pitch of Osc.A is controlled by the output of the S&H module. Also by the keyboard control. The LFO A is triggering the S&H module. At the speed of 7.25Hz the red input signal is being sampled. In this case the input signal consists of white noise wich will give a random input signal to the S&H module. The keyboard gate resets LFO A1. Result: a random pitch modulation on a triggered speed.

The cut-off frequency is controlled by the output of the S&H module. The LFO A is triggering the S&H module. At the speed of 2.56Hz the red input signal is being sampled. In this case the input signal consists of white noise wich will give a random input signal to the S&H module. The keyboard gate resets LFO A1. Result: a random filter cut-off freqency modulation on a triggered speed. This will open and close the filter in a random way.

Basically the same patch. But now the S&H is connected to the resonance modulation input. Result: the S&H's output controls the emphasis of the harmonics in a random way.

Connecting the output of the S&H into the pan modulation input changes the position (left <> right) of the sound in the stereofield in a random way. In this case the output of the S&H is smoothed otherwise it will cause clicking. If you increase the amount of smoothing, the singnal will sweep from left<>right (knob 18).

The output control signal of the S&H controls the pitch modulation input of the synced Osc.A2.

Result: A random changing harmonic content.

Synchronization forces Osc.A2 to restart its waveform cycle, in sync with the waveform cycle of the controlling device. The oscillator will restart whenever a signal present at the sync input increases from 0 units to anything above 0 units. In this case: Osc.A1 at 164.8Hz. The pulse width, fiter cut-off frequentie, resonance and panning is controlled by the S&H's smoothed output as well.

The Noise generator is replaced by a LFO(Up&down).

Result: Using a triangle wave produces a climbing and descending signal.

A simple melodic line can be heard. The reset is used to maintain the same tonal sequence on every note/key triggering.

Using two LFO's you can adjust the sampling speed to match it with the speed of the sampled signal. Both are set to 0.43Hz. Nothing seems to happen, because the sampling is now done at the same value of the ramp wave('going down'). Changing the phase(knob 4) will result in an other 'note' frequency. Changing the speed(knob2) into 0.86Hz. we hear two different notes. Changing it into a ratio 1:3 (0.43Hz.-1.29Hz.) will result in a 3-note sequence. What do you think a ratio 1:5 will bring? Also try 1.44Hz.-6.88Hz.

S&H's output signal connected to the Envelopes modulation inputs: attack, decay and sustain, results in longer and shorter notes. The constant module connected to the overall amplutude will not only affect laudness, but will react on the envelopes modulation output on the filter aswell.

Using three LFO's mixed to one trigger signal will result in a complex rithmic sample reading.

In this patch an Envelope Generator is added as a control signal to be sampled. This results in a more complex structure. Try also a Control Sequencer and Pattern Generator.

The S&H's output conected to the CompreLev modules result in triggering the Left Env and Right Env. Change the setting of the Pattern Gen(the to be sampled input for the S&H module) will result in a different panorama setting, different notes as well. Changing the values of the CompareLev modules will trigger the R&L Env modules different, another panoramic and filter modulation occurs.

LFOA1 can be replaced by Midi Global, synchronizing it to other rhythmic patches.

This patch uses three S&H modules.

S&H module 1: modulates OscA1's pitch, slaves LFOSlvD1and LFOSlvB2, connected to CompareLev1, it triggers ADSR Env1.

S&H module 2: modulates OscA1's pitch, modulates the overall amplitude of ADSR Env1.

S&H module 3: connected to CompareLev2, it triggers ADSR Env2, modulates OscA2's pitch, modulates FilterE2, modulates Delay2&3's time.