From a review by Steve Cummings of MIDI system-exclusive programs
Keyboard magazine, October 1986

Modzilla. You say your Roland Juno-106 is great for Top 40 gigs, but the sounds are just too predictable? You're looking for something like an Oberheim Xpandcr, but on a budget? Check out Modzilla. The programs we've been talking about so far have been utilities, but Modzilla is fun. Even if you're not the kind of person who loves late-night noodlings on a modular synthesizer, you'll find that this program will enrich the sound of the Juno.

The idea behind Modzilla is fairly simple. The program supplies four independent digital LFOs, each of which can be used to modulate any two of the Juno's voice parameters, or one voice parameter and the pitch-bend setting, using MIDI system-exclusive messages.

Before going into detail about how this works, we need to say a little about the programs screen and operations. Essentially, Modzilla duplicates the Macintosh user interface on the lowly Apple II, using a joystick in place of the mouse. Except for the lower resolution of the Apple screen, Modzilla loses nothing by comparison with Mac software. The entire program operates from a single screen with a pull-down menu bar across the top. The only time you'll ever touch the Apple keyboard is when naming a new patch or disk file. The pointer moves quickly and can be positioned accurately with the joystick, and the program responds to commands and parameter changes instantaneously, You'd be right in thinking that this mode of operation is an odd use of programming talent -- but given the limitations of the Apple, Modzilla is a stunning achievement in software design.

Modzilla lets you choose a different waveshape for each of its software LFOs from a series of standard waves, including variable pulse, square, saw, sine, and triangle waves (each of which is offered in both positive and negative polarities), and narrow and wide random waves. A number of more unusual waves can be loaded from the program disk. Rate, depth of modulation, attack time, and delay can be set for each LFO. You can have the LFO move through its wavetable just once, making it essentially an AD envelope generator (though the envelopes can have some pretty unusual structures), or cycle through the wave endlessly.

As you'd expect, a complete set of LFO assignments and parameter settings can be saved in a disk file (groups of eight sets per file). Each of these Modzilla "patches" also includes the Juno voice number and panel settings, which are transmitted to the instrument when you select the Modzilla patch and can be displayed as slide positions on a screen that looks like the Juno's front panel. This lets you use the program as a sort of screwy librarian. Storing the Juno patch along with the internal data makes sense since the effect of your settings depends to a considerable extent on which Juno voice you start with.

One example should be enough to give you an idea what Modzilla will do. A demo patch called "Green #6" had a triangle wave modulating the amount of internal LFO applied to the VCO and the filter, a negative sawtooth on the pulse width and the suboscillator volume, a slightly slower positive sawtooth also applied to the suboscillator and to the filter keyboard amount, and another triangle wave modulating noise volume.

The results of these sorts of modulations are often whizzings, burblings, gruntings, and chirpings that can hold their own against the output of any fancy modular synthesizer. For maximum trance induction potential, you can simply sustain a chord with the Juno's hold footswitch, sit back, and let the thing run indefinitely. The program's authors loosely estimate that a complete Modzilla cycle, with all four LFOs running at different rates, can last two or three months before it repeats. LFO rate is variable from about 20 minutes per cycle to about 10Hz.

If you want more interaction with your music, you can change any of Modzilla's parameters as it plays, including LFO waveshape and modulation destination. Modzilla is a video game for synthesizer musicians, and if you're an addiction-prone personality you may be so busy fiddling with the parameters that you'll forget to eat and sleep.

Another useful provision is that each of the LFOs, the pitch-bend position, or the entire bank of Juno parameters can be separately programmed to reset in response to new keypresses on the Juno or to the instrument's manual LFO trigger, If you use resets and avoid extreme settings on the Modzilla LFOs, you'll get fairly manageable keyboard sounds that have recognizable tonality but are still much more complex that anything the Juno could do without Modzilla.

The current version of Modzilla works only with the Juno-106. As an example of what inspired programming can accomplish on the Apple II with MIDI, Modzilla is a real one-of-a-kind item. Anyone who owns a 106 and an Apple and has the slightest interest in unusual sounds should get a copy.