New Model 416 Meta Expander for the BEMI Buchla Music Easel

via guyd2.com

"The Model 416 Meta Expander is a fully-fledged, standalone breakout-box for the BEMI Music Easel, which provides access to all of the Easel- and Program Card's patch points (effectively doubling the Easel's control voltage possibilities), and greatly extends the Easel's capabilities by having several useful modules build in.

The Model 416 Meta Expander communicates bi-directionally with the Easel by means of a custom-designed Edge Card and a 60-pin flat ribbon cable.

A quick rundown of the Model 416 Meta Expander's capabilities:

Doubling the Easel's patch panel CV's (pitch, timbre, period, etc), with modulation depth controls. This then allows to modulate these parameters with [at least] two sources simultaneously.

Bringing out extra patch points not accessible on the Easel's patch panel. Full control over the Envelope's Attack, Sustain & Release. Voltage control over the Complex Osc's Waveshape Level. Access to all of the Sequencer's steps, and control over its number of Stages. Access to Random Voltages 3 & 4 (the Easel's patch panel only provides RV's 1 & 2).

Trigger inputs for the Sequencer, Envelope, Pulser & Random, opening up the Easel to external synchronisation.
Full voltage control over most of the Easel's switches.

In addition, the Model 416 Meta Expander offers extra custom-designed modules to vastly expand upon the Easel's features:

Two fast Comparators, with threshold control, for pulse generation, with both 3.5mm & banana inputs, separate outputs (2ms @ 10V), as well as a combined output (A+B). They can drive any triggerable module in the Easel.

A Noise module with White, Pink-ish and Slow-Varying Random outputs. Since White & Pink Noise are simultaneously available at Tini-jax & banana outputs, they can serve as both modulation- and audio sources. Slow Random is available at several patch points across the panel.


A Random Pulse Generator (2ms @ 10V).

An inverted version of the ModOsc's output.

A unipolar Inverter, separate from the Easel's build-in Inverter.

AC-coupled hi-precision 3-channel Signal Processor with bipolar Offset control. Each input has a bipolar level control. The summed output is accompanied by two signal level LED's, showing both the negative- and positive excursions.

Last but not least: an officially licensed "Easelified" version of Serge's Universal Slope Generator. This adds an extra Oscillator to your Easel (up to appr. 3.5kHz), a variable-waveform VC-LFO (down to a 10 min. cycle or thereabouts), an extra VC-Envelope Generator, a VC-Slew Limiter, a primitive LowPass filter, a VC-Gate Delay, a Pulse Generator, etcetera... It has two (2) independent CV-inputs (which is unique for a USG), with control over the Rising, Falling, or Both Slopes, and an extra "full-on" CV input. The CV inputs are scaled differently; one does deep modulation while the other reacts more subtle. The USG's unipolar output is available at two banana's and an extra Tini-jax.

Though developed on- and for the Bemi Easel, the Model 416 Meta Expander is 99.5% compatible with the 208r Rev2 clone as well. On the 208r r2, the ModOsc's Range switch is missing, and the ModOsc's output is not present on the edge connector.

The Model 416 Meta Expander comes as a build-to-order product only, and is not available as a DIY- or kit solution."