PLAN B analog blog

Shipping of the Model 28 is to begin in three weeks.

For a complete product description and picture, go here:

http://www.ear-group.net/model_28.html

Product Summary:

The Plan B Model 28 Programmable Tap Clock is the second computer-based product in 
the Plan B line and addresses the need for an accurate tap input-based timing clock for 
analog synthesizers. Unlike other clocks, the Model 28 has no frequency pot -- it's tempo 
is determined by replicating an interval set by two successive depressions of the TAP 
INPUT button, or by syncing to it's PHASE LOCK input to an external clock. The M28 may 
be accurately programmed during a roll-off or three count in live performance - it is 
meant to be played and it's operation has been intelligently designed to support that in 
real time.

Along with the quarter note base duration, the M28 provides separate eighth note tuplet 
and eighth note triplet outputs and approaches these rhythms in the same manner 
musicians do -- by multipling the tap tempo, not by dividing. The last tap interval read 
becomes its quarter note base, with the eighth-notes being base x2 and the triplets base 
x 3. All outputs are held at 50% duty cycle and tempo-accurate within 6 microseconds, 
with a playback range of a quarter note = 1 (1 beat per minute) to 2500 (2500 beats per 
minute).

Along with the three parallel event outputs, the M28 is equipped with a single SERIAL 
OUTPUT which allows the user to construct polyrythmic combinations of the three note 
values, determined by a voltage level present at the SELECT input.

The Model 28's musicality is further enhanced by a series of five ARTICULATION SWITCHES 
which introduce expression by either omitting (a rest) or dynamically accenting each 
degree of the eighth and triplet events (see figure 3). When an accent is selected, a second 
pulse is sent to independent ACCENT outputs which can be routed as a filter frequency 
chiff, or to the Velocity Input of a Model 25 VCA, or to the secondary VC Input of a Doepfer 
A-132, etc. The Accent Outputs are intentionally soft (gates are rounded at the corners) to 
avoid any pops caused by abrupt changes in amplitude. 

Two expanders are planned for the M28.  The 28A will add Triangle, inverted Triangle, 
Ramp and Inverted Ramp outputs to the quarter and  eight note clock outputs.  The 28A 
will begin shipping in June.  The 28B will follow soon afterward and will provide for MIDI 
out of the M28 clock information.

For more information and complete functional description of the Model 28, go here:

 http://www.ear-group.net/model_28.html

Again, the Model 28 is scheduled to begin shipping in three weeks time.