Recipe for producing a sub bass that is both loud and rattles shelves?

Question

The best sound I can come up with is not a sine wave, but a triangle wave. The triangle wave creates a very nice upper and lower shelf frequency that you can both hear and feel. The bad thing with triangle waveform is that it sounds more electronic, there's some noise and its not as clean and smooth as a sine.

I struggle to reproduce this effect with a sine wave and I don't understand why. What is the special thing I need to do to cause a sine wave to rattle my tables?

If I crank the gain up too high on the bass, then compression kicks in and the bass sounds terrible, thick with no harmonics whatsoever, and will not rumble anything, even with the main volume cranked up.

If I lower the gain, it can start to rumble with better harmonics but then I can barely hear the bass.

How can I create a sub bass that sounds loud and has a powerful rumble?

Answer 1

You should try using a noise generator or transform some other noise to lower frequencies by changing its sample rate. Don't use pitch shift because it will introduce many digital artifacts that you won't like.

This way you can get a rumble sound with high momentum in many sub frequencies.

Answer 2

The best thing for you is probably something in between sine and triangle – the latter is itself in a sense something in between sine and square¹, so a good idea might be to use the classical way of interpolating between sine and square: symmetric nonlinear distortion, aka soft clip. In fact, I daresay a bit of asymmetric distortion can't hurt either (it'll more go towards sawtooth or triangle-in-octaves then).

A low sine alone doesn't really work out for a number of reasons. Almost all equipment (and any room) has a pretty uneven frequency response in the low-end, and if the particular frequency you're trying to use is killed in that process then you won't get much of a sound at all. So unless you know exactly under which condition your product will be heard, you should make sure this can't happen. The two main techniques to that extend are: sweeping around the sine to avoid staying on any particular—possibly "bad"—frequency, or adding overtones.

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¹_{Both triangle and square (and, if you will, sine) contain only odd harmonics, for square their natural intensity falls off 6 dB/8ve, for triangle it's 12 dB/8ve and for sine ∞ dB/8ve, so to say.}