I wanted to start a dedicated thread in regard to this as I replied to Steevio a few times amongst others in regard to harmonics but it was in the 'drums in deep house' thread where we were talking about. ( Quite how it appeared in there I don't know but I guess these things have a way of wandering )
Ok, as a grounding, here's where I am. I can read a bit of music, I play keys and I understand theory enough to know what I'm on about. I don't however, understand harmonics. I know 'what' they are, I just don't know note = hz values for example. ( Other than A3 = 440hz in 12 TET )
Might be better to talk about the relevence of sine waves first of all? In fact, I don't even now where to start this as obviously, depending on the waveform, harmonics are completely out of context without it.
Anyway, it's a start and I can bounce off peeps once I know where to begin. ( Oh I do know what sound is, I don't need to begin right at the beginning ) But as an example, I didn't know that a saw wave was created by sine waves.
Harmonics.
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JonasEdenbrandt
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Musicologist here is gonna try to explain what i think you'r asking.
440 Hz = A3 this means you will find the octave at double the Hz 880=A4 also 220=A2 and 110=A1.
Now playing A3 will not just mean you'r hearing 440Hz you'r also hearing the 880 as an overtone. Adding to this you'll hear 880+440=1320 this is an E wich is a fifth to the A. Some were in there u'll get a third as well.
Now this means a simple A is built up of a bunch of overtones (harmonics) these are present in diffrent degrees depending on the instrument and in theory a perfect sine has none of them.
A fantastic thing about harmonics and psychoacoustics is that hearing the overtones from say 440 Hz but not actually hearing the 440 Hz A the brain will fill this blank in and you'll still hear it as an A. This is how opera singers can make themselves audiable threw an orchestra since there voices are very rich with overtones.
440 Hz = A3 this means you will find the octave at double the Hz 880=A4 also 220=A2 and 110=A1.
Now playing A3 will not just mean you'r hearing 440Hz you'r also hearing the 880 as an overtone. Adding to this you'll hear 880+440=1320 this is an E wich is a fifth to the A. Some were in there u'll get a third as well.
Now this means a simple A is built up of a bunch of overtones (harmonics) these are present in diffrent degrees depending on the instrument and in theory a perfect sine has none of them.
A fantastic thing about harmonics and psychoacoustics is that hearing the overtones from say 440 Hz but not actually hearing the 440 Hz A the brain will fill this blank in and you'll still hear it as an A. This is how opera singers can make themselves audiable threw an orchestra since there voices are very rich with overtones.
As been said above, pure sine dont have any overtones, only the fundemental tone is heard. try to lp or hp a sine, youll noticed it doesnt change like saw or square. it only get more quiet. the more you filter, your only cutting the level of the fundemental pitch as there are no overtones in other pitchs to cut.
If youll look at a Triangle, youll see there are more partials in it. or in other words, more sine waves in higher pitch but much lower in their level.
when you lp this kind of wave shape, the first thing you cut are those overtones. that is why you get a different timbre and not just changing the level like with a Sine.
Square:
Saw:
Of course not all waveshapes looks exectly like in the pics ive posted. but they are more or less. depends on the timbre the designer wanted.
raising or lowering a partial, or adding a partial can have a real impact on how it would sound like.
If youll look at a Triangle, youll see there are more partials in it. or in other words, more sine waves in higher pitch but much lower in their level.
when you lp this kind of wave shape, the first thing you cut are those overtones. that is why you get a different timbre and not just changing the level like with a Sine.
Square:
Saw:
Of course not all waveshapes looks exectly like in the pics ive posted. but they are more or less. depends on the timbre the designer wanted.
raising or lowering a partial, or adding a partial can have a real impact on how it would sound like.
Ok, gonna stop you there, thanks too stomper, the syntheisis behind creating a sine from LP filtering is not a thing I am really trying to get to grips with though right now, I do know all that. I understand what you are saying and can fully comprehend that, it's the multiplication and math that I am looking to get..JonasEdenbrandt wrote:Musicologist here is gonna try to explain what i think you'r asking.
440 Hz = A3 this means you will find the octave at double the Hz 880=A4 also 220=A2 and 110=A1.
Now playing A3 will not just mean you'r hearing 440Hz you'r also hearing the 880 as an overtone. Adding to this you'll hear 880+440=1320 this is an E wich is a fifth to the A. Some were in there u'll get a third as well.
Jonas, this is a sinewave right? A multiplication of 440hz = 880 plus 440. Ok, Sounds logical. After that you lost me mate. Why has an 'E' come into it? What are we adding to the perfect octave that makes an 'E', 440's?
Ok, I see the sum, but like I say, I am not familiar with notes to Hz values for 12 TET is there a chart or something so I can reference?
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JonasEdenbrandt
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There are a few fun things you can play around with to get a grip of it. Use a graphic EQ and remove the overtones from a piano note or synth and see what happens with the sound. Also remove all of a sound with sharp Qs at the fundemental and overtone positions and then play other notes into the same EQ and see what notes are unchanged and wich ones share overtones with you'r original note. Also it can be a good lesson to play around with acoustic instruments in a sampler and a EQ to see what makes a guitar note and what makes a piano note. With these you can notice that there not all that different once you just remove a few overtones and change the attack a bit.
Doing these excersises gives a great insight in harmonics and sound design.
Doing these excersises gives a great insight in harmonics and sound design.
Re: Harmonics.
ok mate,AK wrote:I wanted to start a dedicated thread in regard to this as I replied to Steevio a few times amongst others in regard to harmonics but it was in the 'drums in deep house' thread where we were talking about. ( Quite how it appeared in there I don't know but I guess these things have a way of wandering )
Ok, as a grounding, here's where I am. I can read a bit of music, I play keys and I understand theory enough to know what I'm on about. I don't however, understand harmonics. I know 'what' they are, I just don't know note = hz values for example. ( Other than A3 = 440hz in 12 TET )
Might be better to talk about the relevence of sine waves first of all? In fact, I don't even now where to start this as obviously, depending on the waveform, harmonics are completely out of context without it.
Anyway, it's a start and I can bounce off peeps once I know where to begin. ( Oh I do know what sound is, I don't need to begin right at the beginning ) But as an example, I didn't know that a saw wave was created by sine waves.
first wiki / google harmonic series, and or read any basic explanation of subtractive synthesis, it would easier than trying to explain it all here.
has anyone got any good links ?