Very low frequencies and music

[mdlewis]

I've been fascinated by the perception of very low frequencies for many years now and thought I'd share some thoughts and questions. I honestly don't know if anyone gives a poopie. FWIW, I enjoy a lot of old music, primarily because all of the parts need to be played by humans on instruments that obey classical acoustical and electrical physical laws for the generation of sound (e.g., all analog).

Here are two things I believe to be facts (e.g., verified by experimentation under controlled conditions):

1. Human beings cannot hear frequencies below about 20 hz (depending upon age, health etc). Below that humans hear pitch as rapidly oscillating individual sounds. I'm not sure where the changeover to pitch actually occurs, but I'd be interested if anyone knows about research in this area. Is there a frequency range where people differ in this changeover, is it related to physiology, training etc? maybe ear canal size?
2. Humans have an inbuilt subharmonic synthesizer in our brain perceptual software that lets us perceive fundamentals even when we hear a normal harmonic series lacking one - we construct the fundamental in our brain even if it they are not present in the original sound. It think Hemholtz was the first to show this in the 19th century. I don't have any idea why we have this ability, but its the reason why people who believe that they can actually hear much lower think they can. [If this is new to you, please understand that perceptual hearing tests of this sort need to conducted under carefully controlled conditions with pure sine waves which are composed of only one frequency. You can't do this with your bass guitar].

In modern times we now have the ability to create low register sounds of arbitrary harmonic composition, envelope, and execute them at any speed without any relationship to the physics of the analog generation of sound This means that the old play with the kick and only the kick approach is easily replicated mechanically. One sees this throughout current commercial pop where the programmed percussion is actually pitched (no bass instrument required).

Interestingly, these days one sees extended range bass guitars that are more like harps - instruments that cover a range of frequencies that widely exceed the normal range of a bass part in a typical composition. I see these instruments as more like pianos - their role is more in solo performance or in chordal support.

I enjoy reading about those players who play instruments that are tuned extremely low and I'm interested in what you are trying to accomplish musically with this approach. I'd love to hear from you how musically how this enables you to achieve your vision. I would imagine that playing in those regions limits the amount of motion in your lines and am wondering if that's a concern or maybe I'm just not understanding something critical. If there a physical effect you are trying to achieve? Or is there something perceptual going here (e.g., are you able to hijack the inbuilt subharmonic synthesizer to achieve new tonal effects?).