Tone just means a sound "Has Harmonics."
- A pure sine wave is a pure note. It has no harmonics. It has no tone. It's just that one frequency.
- The moment any harmonics are present, that note has tone. In general we're talking about harmonics in the
harmonic series. Harmonic partials occur at predictable frequency ratios up the spectrum.
- How that tone sounds depends on a few things: Which harmonics are present, and how much of each harmonic exists. That's why a clarinet sounds like a clarinet and a tuba sounds like a tuba. They have different harmonics present at different levels.
So, for example, a Square Wave's tone is an infinite series of odd harmonics: Fundamental, 3rd, 5th, 7th, etc. all the way up. And each harmonic's amplitude decreases proportionally to its harmonic number 1/n. So the third would be the amplitude of the fundamental times 1/3.
A Saw Wave's tone is an infinite series of every harmonic, with the harmonic's amplitude decreasing proportionally to its harmonic number 1/n.
You can create either Square Wave or Saw Wave with enough Sine waves at their harmonic values, with the correct level ratio.
What does this mean in terms of Bass? Kinda the same as it means in terms of any other instrument. The tone of a bass is just how much of what harmonics exist when you play a note. That's it. All the talk of "good tone" and "bad tone" is all subjective. Tone is just a descriptive term. There's no such thing as good tone or bad tone.
Tone is subjective; tone is contextual.
Does it sound good to you when you play your bass in isolation? Then it's good. When you play in a group or a mix of other instruments, does the mix sound good? Then it's good. Does the mix sound bad? Adjust your tone (aka adjust the amount of different harmonics present in your signal to fit better in the mix. Also, ideally, the other electric & electronic instruments should be adjusting their tone to the arrangement, instrumentation, and mix as well, but that's another discussion.)
I generally have devoted little time to this aspect, just a tweak or two tops
You're doing it right. And i'm saying that as a sound engineer, not a bassist.
Doing too much with tone is worse than doing too little. And generally, when you get into a mix, simple, broad stroke adjustments are better than dozens of surgical ones. The surgical fine tuning is really only useful in the studio, after the recording is done, and an incredibly unique and weird set of circumstances show up in the mixing phase, that probably should have been addressed in the recording/tracking phase, but it's too late because that's already done and you can't go back and re-track.
From my engineering perspective as a bass player i generally treat tone like this:
- Plug in and leave everything "flat"
- Play.
- Does it sound good?
- If not, adjust. (And the adjustment might only be a slight tweak. Great gear gives us a lot of options and flexibility. But we don't need to use every feature all the time. Not every knob needs to be twisted. A great adjustment might be adjusting one fader on a 12 band EQ +/-3dB. Maybe it's just a slight bump on the Amp's EQ. Maybe i'm hitting the first two LEDs of GR on my compressor. Hell, in the studio, sometimes i've run a channel through a piece of gear like an SSL channel strip and adjusted none of the knobs because it just sounded good running it through the gear as-is.)