Waldorf Micro-Wave

This is an article culled from archive material, circa 1997.

The Micro-Wave was one of the instruments at the vanguard of the currently trendy analogue revolution. In essence, the Micro-Wave is a modern rackmount MIDI version of the classic PPG Wave synthesiser designed by Wolfgang Palm. The PPG Wave combined a digital synthesis section (8-bit, highly-harmonic wavetables which could be swept for dramatic timbral change) with true analogue resonant filters.

Rather than being a truly vintage instrument, the Micro-Wave (designed and built by Waldorf GmbH, since PPG folded in 1986) is a modern MIDI device with the features that one would expect, including multitimbral operation and a comprehensive modulation architecture. However, it still carries the original PPG wavetables (in fact, Palm designed the Micro-Wave's custom DSP), and is quite capable of making all the stark, metallic tones associated with the PPG. In fact, the original Wave 2.3 patches ported to the Micro-Wave sound quite authentic.

The modulation architecture is impressive, bearing a resemblance to the matrix modulation scheme found on the Oberheim Xpander and Matrix-6R. A sideband modulation scheme allows one modulator to regulate the amount of a second. The internal wave envelope can be looped (although it is nowhere near as sophisticated as the function generators found on the Gearhead/Morpheus. Filter resonance can be controlled separately from cutoff frequency.

The latest revision of the Micro-Wave operating system adds some new features, such as algorithmic wavetables. These allow waves to be constructed "on the fly" by loading parameters for generating the waves, using frequency modulation, waveshaping, or various other synthesis methods. What is more, the table parameters can modulate one another, so that a table can change algorithm part way through. So, the Micro-Wave is the only synthesiser which can change synthesis algorithm part-way through a note.

One irritating feature is the association of the multiple edit buffers with patch locations. Program changes will recall edited patches rather than stored ones. If the instruments of a multi setup share a patch location, then edits of the separate instruments will interfere. This design is quite nice for front-panel editing, but a headache with a computer-based editor.

From some points of view, the Micro-Wave is underpowered: it only has eight voices, there are no onboard effects, and the (four) monophonic individual audio outputs, if activated, steal voices from the main mix. However, such criticism misses the point: the Micro-Wave is very good at what it does, and the sound is such that multiple layered voices, or flashy onboard effects, are largely superfluous. Anybody wanting an instrument with lots of voices should buy something boring like an Alesis QuadraSynth.

People keep asking me what the Micro-Wave sounds like. My answer is always the same: go and buy a copy of the EXIT album by Tangerine Dream. Anyone who likes the sounds on that album (which are almost exclusively PPG Wave) will like what a Micro-Wave can do. However, it does require careful programming. I have had mine for nearly six years and am still learning how to program it well. However, the factory presets give you plenty of encouragement to begin your own programming, since they stink.

My Micro-Wave, being one of the first units in the UK, has the original rotary encoder dial. The red knob for this dial was made of cheap plastic (which explains why my unit has a custom acrylic paint job), and the encoders themselves are prone to corrosion, causing problems when programming via the front panel. I believe that later machines (with the good-quality red knob) are free from this problem.