What shapes instrument sound!

[Randy Bassinga]

I have a project build here

https://www.diyaudio.com/community/threads/instruments-amp-y4-trio.383281/
While learning to make custom filters and eq for this, I had a moment of ponderings and came up with this. It could be drivel for all I know as I am still taking baby steps with electronics. Please point out the holes in my understanding if you find this of interest

Learning how filters and tones are configured raises another question. I don't think it's only eq'ing of particular frequencies that shape sound. From careful listening to the harmonics (am I using this term correctly? Please educate) produced around each fret and how that fret is played, I have come to the belief that to shape sound from an instrument;

1 - multiple bands of eq in the relevant area of the instrument, at least 4 bands for a bass instrument. I think apart from the level pot, this is the first shape step to shape a frequency curve, but this doesn't alter the "voice"

2 - each band should have two parallel circuits that are more complex and contain a high pass to one side and low pass to the other. These two adjacent circuits need level pot, range pot, delay pot and reverb pot. The "voice" circuits to then mix back into the that tone bands output

This is the only way I can see to truly shape a bass guitar "voice" with analog. So each tone band consists of tone knob, upper harmonics level and reverb and lower harmonics level and reverb. My own voice is fairly low to where a lot comes from the subwoofer too. I can "shake" and add inflections while singing to suit the moods of different songs. Indian music composer R.D. Burman had his own unique singing style that he distorted with gargling type sounds at various reaches. With this, I infer that a distortion level on each of that three parallel circuits per band will do a job too

Basically this means that each band of the tone controls get 9 knobs or so. This is just my thots from what, I don't know whether it's on to something or coming from ignorance. After I finish the amp/cab to a usable level, I am going to seriously learn to implement this. I haven't seen it done like this before and if I am the first one to think of this break down then I would enjoy it to be known after me as the "Bassinga" (bass singer) system. If it's already old news to split each band and adjust harmonics individually like this, then I hope someone points it out

 

[mandu]

A flute does not sound like a guitar or a guitar does not sound like a violin at the same pitch.
Main distinguishable differences to tone are.
1. Fundamental frequency + harmonics in different mix levels.
(this ratio could vary with pitch)
2. Attack, Decay, Sustain and release of amplitude.
(Distinguish between a bell and a pad)
3. Attack, Decay, Sustain and release of pitch.
(Initial pitch changes to drums, blowing instrument etc)
4. Attack, Decay, Sustain and release of harmonic filters.
(Like brass instruments)
5. Pitch modulation, Amplitude modulation with delay
6. Portamento and playability.
(How the notes glide between different semitones.)
7. The tone created by the construction material
(the tone may change over a wide range of pitch change)

Until now there are no electronics that can perfectly reproduce the wide range of any instrument.
A modelled sound may reproduce only up to a certain key range but after that shows it's fake teeth.
Which led to sampled sounds.
Unfortunately with lots of pitch and harmonic correction in those sampled libraries, they sound fake.
Ex: Upper registers of a string may sound like a flute. A piano may lack the sound of the wood and ambience.
A string sampled instrument claiming 60 players recorded may not have that ambience.
All electronic sounds sound like as if they sit inside your ears.
Most electronic musical instruments are perfectly pitch locked, which is never the case in reality.
The rich harmonics sound of an accordion or piano or violin ensample are absent in electronically produced sounds.

When you try to create something to produce electronic music, whatever technique you use, will never sound like an original.
But don't think this message is discouraging. Just let you know the outcome of any electronic music design.
Keep researching.
Regards.

 

[Mark Tillotson]

I'd add
8. change in relative phase of fundamental and harmonics over time.

This can be seen by synthesizing say a 200Hz and 600.1Hz tone pair - the timbre will change as the phasing varies over the
10 Hz repeat period (2000 cycles against 6001 cycles).

And
9. stray byproduct noises like fretting, buzz, sibilance and so forth - atmospherics too.

All electronic sounds sound like as if they sit inside your ears.

Well not if you play them through a monitor - as a corollary headphones can make any sound go inside your head.

One of the most impressive electronic sounds I've heard is synthesized thunder on a Moog put through 1000+W PA for
a production of The Tempest in a small theatre. That wasn't between the ears I can assure you!

 

[Gnobuddy]

A modelled sound may reproduce only up to a certain key range but after that shows it's fake teeth.
Which led to sampled sounds.

More recently, there is physical modelling, which models the physics of the actual musical instrument, rather than just trying to generate a waveform.

For example, by applying Newton's laws of motion to a simulated piano string, with simulated mass, tension, and other properties, struck by a simulated hammer with simulated felt on its face, with simulated hammer velocity and mass. The string is mounted to a simulated piano frame with a simulated piano soundboard. And so on.

This was computationally impossible in the early era of synthesized sounds, but as cheap computing power has grown exponentially over the years, it became possible.

This is apparently what PianoTeq does, and it has had rave reviews for years: https://www.modartt.com/

-Gnobuddy

 

[rayma]

Much research has been done in the past few decades. Some examples:
https://ccrma.stanford.edu/~jos/jnmr/jnmr.pdf
https://www.music.mcgill.ca/~gary/618/