Released in 1981, Kraftwerk’s Computer World was astonishingly ahead of its time. So much so, that Rolling Stone added it to their Top 10 EDM albums of all time. Not bad for a record that’s 35 years old!
The album includes several how’d-they-do-that sounds, some of which were sourced from digital toys, notably Texas Instruments’ Speak & Spell. Others were innovative approaches to analog gear that blurred the line between melody and sound design. This month, we’ll examine two of those sounds using a synth that routinely appeared on the band’s equipment lists—the ARP Odyssey—using the recent Korg reissue.
Appearing on several tracks (“Numbers” and “Computer World 2,” specifically) is a percussive effect that sounds like a laser zap, affectionately known as the “thwip.”
Step 1: The key to the sound is a self-oscillating lowpass filter. Start by turning the volumes of both oscillators to zero in the filter mixer, then set the filter cutoff to zero and resonance to maximum. On the Korg reissue, there are three filter circuits to choose from. For this recreation, I used Type 1, but if you want an even thinner sound, Type 3 is a good choice.
Step 2: From there, it’s just a matter of modulating the cutoff and VCA using fast ADSR settings—0 for the attack, sustain and release, and a miniscule amount of decay (around 2 to 5%). The result should be an extremely short, chunky zap.
Step 3: For that final Kraftwerk polish, thin out the sound by raising the highpass cutoff to around 80%, then add a touch of tempo-synced stereo delay.
Another unforgettable sound from Computer World is the rising synth that pervades “Home Computer.” Over the years, I’ve seen descriptions of this sound that suggest an arpeggiator is the source. Nothing could be further from the truth. The secret sauce for this patch is a free-running, upward sawtooth LFO, which the Odyssey readily offers.
Step 1: Start by setting VCO-1 to LF (low-frequency) mode for use as the LFO. Because the Odyssey’s sawtooth waves are specifically upward ramps, this is perfect. Dial down the frequency to about 25% (about 0.5 Hz).
Step 2: To apply this modulation, you’ll need to use the S/H Mixer, selecting VCO-1 sawtooth as the input and raising the value to maximum. Additionally, you’ll want to switch the S/H trigger to keyboard, so that each key event passes the sawtooth through wherever it is in its cycle.
Step 3: The rising tone itself is a sine wave, which the Odyssey can produce with its self-oscillating filter. Here, I’ll select Type 2, as Type 1’s gain structure gives the resonance too much saturation. Raise the resonance to maximum and the cutoff to 50%. The ADSR envelope modulates only the VCA, so leave the filter envelope amount at zero. Next, set the attack, sustain and release to zero, with the decay around 10%. Applying a 16th-note sequence to this sound should now result in a repeating sine wave at a single pitch.
Step 4: To add the rise, switch the filter modulation source to S/H Mixer and increase its level to about 60% and fine tune from there. As a final tweak, add a touch of delay and reverb.