If you're trying to win at a coin toss, there's no way to game the system. Regardless of whether you start with heads or tails, the outcome's always going to be a 50/50 split.
When it comes to harmonic distortion parameters there are also only two choices—odd or even—but now it is possible to game the system depending on where one focuses.
Let's start with a bit of a refresher.
When we look at distortion numbers we're always happiest when they are low. In fact, the lower the better. How we arrive at those lower numbers and which numbers we're talking about can make a big difference in sound quality. That is because odds and evens, unlike heads and tails, matter. Their addition to the musical signal is what defines distortion—the alteration of an original signal by introducing unwanted odd or even harmonics.
Odd harmonics are frequencies that are odd multiples of a fundamental frequency (e.g., 3 kHz, 5 kHz, etc. for a 1 kHz baseline), while even harmonics are even multiples of the fundamental frequency (e.g., 2 kHz, 4 kHz, etc. for a 1 kHz baseline). They are, by definition, unwanted audible artifacts and each contributes its sonic signature to the sound.
Even harmonics are more acceptable than odd harmonics. They are warmer, more enjoyable, like smiling guests at a party, as opposed to the hard edged grumpsters that irritate and create tension in the room.
As a designer, like a party coordinator, you're going to want to choose circuit topologies and active devices that emphasize the even harmonics as opposed to the unwanted odd guests. Topologies that focus on the lowering of negative feedback while maintaining performance, and active devices like FETs and vacuum tubes as opposed to BJTs are wonderful starting places for building warm and inviting musical circuits.
While we can't guarantee a winning strategy for the flip of a coin, we certainly can ensure that what we build can lean in the sonic direction we hope for.
Heads or tails? Odd or even? It matters.
