## Help, generate harmonics

Sound synthesis techniques, DSP and related mathematics

Moderators: electrogear, exonerate

### Help, generate harmonics

Hello, How can generate harmonics (even, odd) without distortion?

sorry for my inglish.

Thx,

Marco S.
JuzamDJ
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### Re: Help, generate harmonics

MichaelBenjamin
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### Re: Help, generate harmonics

MichaelBenjamin
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### Re: Help, generate harmonics

Chebyshev polynomials are indeed the way to go, but avoiding aliasing distortion with these is tricky in SM. If anyone solves it properly, please let me know!
Andrew J
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### Re: Help, generate harmonics

cant one not simply slap your oversampling implementation right and left to make it sound brilliant at 96khz?
i only used this to get some sinewave harmonics so far, didnt use it with a full range signal.

btw someone knows a 1.5 octave powerchord shaper? or any approach that might get me to it?

MichaelBenjamin
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### Re: Help, generate harmonics

MichaelBenjamin wrote:cant one not simply slap your oversampling implementation right and left to make it sound brilliant at 96khz?
i only used this to get some sinewave harmonics so far, didnt use it with a full range signal.

btw someone knows a 1.5 octave powerchord shaper? or any approach that might get me to it?

The filters in the oversampling kit aren't good enough to clean up the 4th and 5th order harmonics. I need to try it in C++ to see if using double precision maths sorts it out.

For a powerchord, you'll want the 3rd harmonic.

Harmonics
1 - Fundamental
2 - 1 octave up
3 - 1 octave + a perfect 5th (i.e. power chord)
4 - 2 octaves up
5 - 2 octaves + a perfect 3rd
6 - 2 octaves + a perfect 5th
7 - doesn't correspond to an interval (ugly!)
8 - 3 octaves up
Andrew J
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### Re: Help, generate harmonics

JuzamDJ wrote:Hello, How can generate harmonics (even, odd) without distortion?

sorry for my inglish.

Thx,

Marco S.

There is always distortion if you generate additional harmonics you just can minimize it.
Come and visit my Blog: Variety Of Sound
bootsy
essemilian

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Location: Frankfurt, Germany

### Re: Help, generate harmonics

Yes, many enhancers work that way. Split of a duplicate of your main signal then filter>>distort>>filter - then mix that back in with the original signal. The kind of distortion is obviously still important if you need control over the exact kind of harmonics added though - a big influence on this is how symmetrical the distortion above and below the zero axis.
Feel free to use any schematics and algorithms I post on the forum in your own designs - a credit is appreciated (but not a requirement).
Don't stagnate, mutate to create. Without randomness and serendipity the earth would be just another barren rock.

trogluddite
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### Re: Help, generate harmonics

i figure he means keeping it from being atonal i.e. focused on notes.

harmonics are seperate frequencies that lie any where along the 12 octaves and are not unrelated to the main frequency, for example a triangle can be approximated by adding 20 sine waves together in small amounts.

in additive synthesis, you put in extra oscillators, in substractive, you use filters to substract, usually synths are a mix of both, in any sound flow system you like.

over time you learn all the ways to add as much sound to the main frequency even with each their own seperate LFO, and you have to find forumulas to create as much related sounds but force them to be mostly close to the main one, the more closer they are to the main, octaves, the less distorted it sounds, in a gradient from 0 not close at all to 100 and all the percentages of closeness in between. that is what you have to control

datsound
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