Elektron: SidStation MOS 6581 Synthesizer

If I had put the same effort into my homework as into manually copying BASIC programs from Compute! magazine into my Commodore 64 in the early 80s, I would now be writing legal pleadings or prescriptions instead of reviews of video game synthesizers. Since then, I have been keeping one of my old C64's in the closet, waiting for the day I would spend seven hours coding to generate about two minutes of lo-fi sample material. Fortunately this day will never come thanks the Elektron SidStation, a fully-functional MIDI synthesizer built around the C64's famous MOS 6581 Sound Interface Device (SID).

The Commodore 64 was released in 1983 and quickly begat one of the most active hacker communities ever, in no small part due its unique sound source. Designed for Commodore by Ensoniq-founder Bob Yanes, the SID originally included four oscillator waveforms, a programmable filter, and three-note polyphony. It was the most advanced sound chip of its time. Visionaries like Rob Hubbard saw the SID's possibilities and changed video game music forever with his classic music to C64 games like Confuzion and Thing on a Spring. The SID's three-note polyphony inspired a unique genre in the countless 4- second videogame "songs" that rewarded the passage to the next level of every C64 video game, and these songs eventually led to the SID's own proprietary "SID Song" file format. To this day, software SID Song players are available for most computer platforms. (In SID Song mode, the SidStation functions as a sound module for these players.) The SID was even behind the first popular software synthesizer, the C64's great Music Machine cartridge. By the late 90s, just as it looked as if the SID's famous sound was to be committed to remixes, samples, and software emulation, the resourceful Swedes at Elektron stumbled onto 1000 or so SID chips and used them to build the classic synthesizer that never was.

The SidStation stretches the SID's standard VCO/VCF/VCA architecture to its limits to provide all the basic functionality of a contemporary synthesizer and to offer all the SID's power from a smart user interface. Although the three-oscillator SidStation has only one filter, basic modulation routings, and two standard ADSR envelopes, it boasts four independent LFOs, a flexible arpeggiator, four assignable real-time control knobs, and contemporary MIDI functionality that includes LFO and arpeggiator sync, SysEx capabilities, and other updated functions. Despite the small LCD display, the user-interface is quick and intuitive thanks to four assignable control knobs that send MIDI CC data, a full numeric keypad, and a snappy data knob for easy patch naming. To further simplify editing, the interface's "Zero Menus" allow lateral movement between similar functions. For example, you can move directly from the Vibrato menu of Oscillator 1 to the Vibrato menu of Oscillator 2 without having to back out of Oscillator 1's menu hierarchy. Unfortunately the interface is always in "performance mode," requiring you to press "Enter" to select each patch rather than having them continuously accessible from the data wheel. Aside from this complaint and the strange fact that the keypad can not be used to input numerical parameter values, the SidStation's user interface won't hinder your inspiration.

The SidStation's quartet of LFOs is a great example of the resourceful design sense that characterizes the SidStation throughout. In addition to providing an array of LFO waveforms, including Sample & Hold and "Flat" (a non-oscillating, pure DC voltage useful as a foundation for incoming MIDI CC messages), the SidStation allows you to "lace" one LFO with another to achieve complex LFO waveforms, in what is essentially LFO frequency- modulation. Practical use of this includes creating staircase modulation by modulating a low-frequency triangle wave with a high-frequency pulse wave. The resulting LFO waveform can modulate oscillator pitch or filter cutoff, and either the carrier (triangle) or source (pulse) wave can be sync'ed to MIDI clock for different rhythmic effects. Similarly, any two individual LFOs can be "mixed" (presumably summed) in any proportion, creating more hybrid LFO waveforms; and an LFO can even be mixed with itself, creating even more unpredictable modulation effects. The LFO modulation can also be set to fade in from zero as a note is triggered; it can be restricted to values above zero; and its waveforms can be inverted so that, for example, a slow filter sweep can begin above or below zero. All these modulation possibilities are easily accessible not only via SidStation's aforementioned Zero Menus, but also because an individual LFO's menu is directly accessible from the relevant parameter menu of the oscillator(s) it is modulating. Overall, the SidStation's shrewd LFO implementation is a shining example of how a limited number of resources can be combined and reworked to provide great functionality.

But let's face it, although the SidStation is a design feat that coaxes so much from so little, its overall functionality is nothing special by today's standards. Why not spend the same amount of money on any one of the polyphonic Virtual Analog/FM synthesizers that have the functionality of ten SidStations? Because none of these will achieve the SidStation's authentic 8-bit sound. Lately, synthesizers like to slum it with their onboard distortion circuits that attempt to "dirty up" a sound. This often results in the sonic equivalent of Vivienne Westwood's pre- ripped, designer Sex Pistols attire. Conversely, the SidStation is as dirty and funky as your soaked Effigies shirt after a six-band Sunday matinee at CBGB's.

The SidStation's organic grit is primarily due to its colorful oscillator interaction and its unique filter distortion. Each of the SidStation's three oscillators includes five waveforms, oscillator hard-sync, ring modulation, pulse-width modulation, vibrato, arpeggiation, pitch transposition, and three-note polyphony-as one might expect in a contemporary analog synth. The difference is that the SidStation's various oscillator synchronizations create extraordinary, ripping timbres that must be heard to be appreciated. These gritty ring modulation and oscillator sync sounds have a completely different character than their analog counterparts, and they are dirtier and more colorful than what you would expect from an FM or other digital source. The SidStation's Oscillator section also provides a unique Waveform Table functionality that allows you to assign a sequence of waveforms for each oscillator to be played when a single patch is triggered. Unlike the famous wavetable functionality pioneered by Waldorf and Korg, the SidStation's tables are explosive and abrupt, more suitable for complex percussion sounds and jagged polyphonic blasts than evolving pads. Each oscillator's table allows you to choose any number of steps to be played at any frequency and for each step, a waveform or pause, hard-sync and/or ring modulation, and a pitch.

Like the SidStation's oscillators, its low-pass filter has a brash and beautiful distortion that is truly unique. Devoid of the chirping sine waves of analog-filter self- oscillation, the SidStation's filter seems to resonate and distort lower in the frequency range, as if its resonant peak was much lower than its cutoff frequency. In fact, the filter does not self-oscillate, and its resonant Q is wide and blunt by analog standards. Instead, it seems to have much more of the phasing distortion of analog filters; it does serious damage to the oscillators to which it is applied, creating uniquely visceral and unpredictable filter distortion. The SidStation also provides band-pass, low/band-pass, high-pass, low/high-pass (band-reject), and band/high-pass filters, but no comb filter. The SidStation also allows you to combine all these filters together, and according to the poorly-translated (and often-amusing) manual, this provides "some strange filtering yet to be understood by a human being." The filter, like other aspects of the SidStation, adds an aleatorical element to its sound synthesis. In fact, much of the fun of programming the SidStation is in its unpredictability.

Unfortunately, some of this unpredictability can be hard to handle, as there are inevitable drawbacks to using early-80s technology. With certain patches, the SidStation is extremely noisy. A gate is mandatory, but often the threshold must be set so high that it softens the SidStation's attack. The SID's ADSR envelopes also come with some strange timing problems, but nothing that a negative-delay value in your MIDI sequence won't remedy. Predictably, the SidStation is also a bit unstable and sometimes crashes during SySex dumps and other heavy lifting. But perhaps the worst consequence of the old technology is its dwindling supply. At the time of this writing, Elektron had about 100 SID chips left, and the SidStation's price is sure to increase as the supply decreases.

I've used my SidStation consistently for over two years now, and its special sound and quick, hands-on user- interface give it a central place in my studio. Also, note that SidStation sounds are available on at least one extensive sample CD, so if you are a preset-loving DX7 user looking to complete your collection of 80s sounds, save your time and money and buy the CD. The SidStation does not instantly yield pleasing sounds, and it does not provide the instant gratification and camp value of a Gameboy Nanoloop or bent Speak & Spell. Instead, the SidStation is a powerful and expressive tool for the curious sound programmer interested in the strange world of 8-bit SID synthesis, and it takes practice and patience to tap into its beauty. ($950 MSRP for numbered "Final 100" edition; www.sidstation.com)