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Motorboating is not a colloquial term for all oscillation. It's a very low frequency instability consisting of a train of pulses which, when played through a sp

Motorboating is not a colloquial term for all oscillation. It's a very low frequency instability consisting of a train of pulses which, when played through a speaker, sound like an internal combustion engine with a short exhaust. The op-amp oscillation the article is talking about occurs in the radio frequency range. Tiny parasitic capacitances induce 180° phase shift at some very high frequency where the op-amp's open loop gain has dropped to unity. You can't hear this directly since it's not in the audio range. It brings about distortion. The amp may pass audio signal, but the oscillation prevents it from performing properly.

ericwood 2y ago
In the contexts I was talking about (hobbyist DIY guitar pedal forums) motorboating is often used as a catch-all for many types of oscillation, probably because the symptoms you describe are a very common error. Sometimes you get lucky and can tune the resulting oscillator by turning the guitar's volume knob! I wasn't trying to assert anything about the article, just responding to a comment about desired op amp imperfections in guitar effects. It's fairly common practice to bandwidth limit high gain op amp stages to avoid the issues discussed in the article, amongst other things.