Using psychoacoustic theory to create even more epic drops?

[SunkLo]

There's no phase cancellation from having another sine an octave up. Or any other multiples of the base frequency.
I usually just buss my subs to a second track with saturation and a highpass on it. It usually has a bit of FM feedback to generate harmonics as well.

[Ficticious]

Oceania hAs a lot of pitch shifting from midrange and low end frequencies going on on his bass. Try listening to him a while.

Also as said many times its proven that people love higher frequencies more than lower frequencies because of the detail. Thats why pianos/synths and other things are said to be "beautiful" but skrillex's tracks are "in your face" because of the distortion, people don't like heavy distortion which is why those songs make you go deaf after a while. Low frequencies can hardly be heard so for now, these generally don't hurt the ears

[FAARE FACED]

There's no phase cancellation from having another sine an octave up. Or any other multiples of the base frequency.
I usually just buss my subs to a second track with saturation and a highpass on it. It usually has a bit of FM feedback to generate harmonics as well.

Well, allow me to doubt that.

I'm not that sure about the scientific facts behind that, but I had a weird rumble when doing so.

Could you explain ?

[GenericNameHere]

OK. So distortion is good, but too much is bad ... or hazardous to your health.

And I thought sin waves don't have much in the way of harmonics, and thus, if two sin waves were played in sync, two octaves apart, there would be no phase cancellation, right? Don't tell me it's one of those theoretical, " in isolation, and only if it's a pure wave," shit.

I tried using seven cutoff/low pass filters on a deep/low end sin wave, qnd check what happened under a parametric EQ, and it looks like there are some "phantom" harmonics present in a "normal" sin wave. Is this theory even right? Also do cutoff filters alter the source on both sides? What I mean is that it's common knowledge that a low pass filter attenuates the frequencies above the cutoff point, but does it boost the frequencies below the cutoff point as well?

How do you guys feel about using square waves for basses? It could make a bass you could feel and hear, right?

[Talált]

this is some duuuumb shit i just read.

maybe you need to twiddle a few more knobs

[GenericNameHere]

this is some duuuumb shit i just read.

maybe you need to twiddle a few more knobs

Yeah, and you have it all figured out, right? That's why you're just RACKING UP DEM Youtube and SC views. Please teach me how to be as awesome as you. I beg you.

[SunkLo]

There's no phase cancellation from having another sine an octave up. Or any other multiples of the base frequency.
I usually just buss my subs to a second track with saturation and a highpass on it. It usually has a bit of FM feedback to generate harmonics as well.

Well, allow me to doubt that.

I'm not that sure about the scientific facts behind that, but I had a weird rumble when doing so.

Could you explain ?

Their periods are perfect multiples of each other, meaning they're locked in phase. The relationship between the phase of the higher one to the lower one will always be 2x, since the upper sine's frequency is double the lower sine's.

If you set the upper sine's volume to half the lower sine's (-6dB), and then tweak to taste, it should sound good.

[CreamLord]

maybe you need to twiddle a few more knobs

K

[Barka]

And I thought sin waves don't have much in the way of harmonics, and thus, if two sin waves were played in sync, two octaves apart, there would be no phase cancellation, right?

Right!

I tried using seven cutoff/low pass filters on a deep/low end sin wave, qnd check what happened under a parametric EQ, and it looks like there are some "phantom" harmonics present in a "normal" sin wave. Is this theory even right?

Spectrum analyzers will show other harmonics due to the way they work, but why put a low pass on a sine though?

Also do cutoff filters alter the source on both sides? What I mean is that it's common knowledge that a low pass filter attenuates the frequencies above the cutoff point, but does it boost the frequencies below the cutoff point as well?

Yes! Well normally, they don't and shouldn't, unless you use a high Q, but minimum phase filters alter the phase, which could actually change the signal on the other side of the cutoff.
Watch this explanation: http://www.youtube.com/watch?v=efKabAQQsPQ

How do you guys feel about using square waves for basses? It could make a bass you could feel and hear, right?

They work really nice sometimes, I often use lowpassed squares in house music.

[OfficialDAPT]

I find a way to get a nice fat subbass is using almost a pure sine wav but a touch of saw, so that those dudes on 3 dollar earbuds can still hear it. also using another sine wave at half volume an octave up works. you can even add another one at 7 semitones above that one. then lowpass of course.

[Turnipish_Thoughts]

And I thought sin[e] waves don't have much in the way of harmonics...

Not quite right. They don't have any harmonics. That's the definition of a 'sine' - 'wave'. A sinusoidal oscillation, in this case one existing in the audible frequency domain. It describes the nature of the fluctuation in the pressure coefficient of the medium (air in this case). In layman terms it is a singular vibration. Any harmonics would be separate vibrations adding to the sum. In practice, that would be separate sine waves stacking above (and/or below) the fundamental frequency.

...and thus, if two sin waves were played in sync, two octaves apart, there would be no phase cancellation, right?

Again, not quite right. 2 sine waves with the same phase running at the same frequency would cause no cancellation. In your case though the 2 octave discrepancy would cause cancellation, as the standing waves are fluctuating at different absolute frequencies. This would lead to a difference in the position of the amplitude peaks of each wave along the time axis, leading to cancellation in the sum.



In this example Red is the fundamental, Green is the first harmonic; and Blue is the sum. Note the phase cancellation. Keep in mind that this image expresses a fundamental and the first harmonic. A picture of the second harmonic would look almost identical, except you would have 2 small equidistant dips in the sum instead of one, as the peak amplitudes of the harmonic would cancel the opposing force of the fundamental when they are </180/> degrees out of phase (but obviously in a smoothly iterating fashion, you can picture it in your head I'm sure.)

The Overtone Series of a fundamental are a series of fixed integers, as expressed in Laplace's Equation in fluid dynamics and Harmonic function. They are the building blocks of timbre in psychoacoustics. Any element other than the fundamental sine wave oscillating at the base frequency of a sound, is essentially timbre; and all sounds in nature are made this way*, inescapably. A square wave, for example, is simply a series of stacked sine waves with a specific equation applied to the amplitude distribution of consecutive harmonics.
*Read the part on Spectrum

Don't tell me it's one of those theoretical, " in isolation, and only if it's a pure wave," shit.

So when you say this it's kind of difficult to give you a proper response because you're actively disregarding the correct answer. Everything is both never, and always in isolation, in as much as even things seemingly whole can be broken down in to their constituent parts. And in this respect sound, as built from pure sine waves, do always theoretically exist in isolation; yet are also part of a sum that is never purely sinusoidal in nature. This is the nature of sound and it simply is something you're going to have to become accustomed with (theorizing over it's make-up in terms of isolated, interacting parts) if you wish to master the subject.

I tried using seven cutoff/low pass filters on a deep/low end sin wave, qnd check what happened under a parametric EQ, and it looks like there are some "phantom" harmonics present in a "normal" sin wave. Is this theory even right?

Using a filter on a sine wave is the same as moving the amplitude fader on your mixer, a filter attenuates or boosts the frequencies at a given point on the spectrum. As a sine wave is expressing something at a single frequency (an oscillation vibrating at a given speed in Hertz). The point at which the filter begins to effect the sound will simply be attenuating the amplitude in the same way as decreasing the signal's amplitude via the track fader, in essence it is exactly the same thing.

By 'checking under a parametric EQ' are you referring to a frequency analysis function on the EQ's GUI? In which case any harmonics you may be seeing could be coming from a number of places.

• The type of EQ you're using could be introducing distortion to the audio signal depending on what type of filtering the EQ the unit is modeled on.
• The filter could also be performing a similar function as the EQ possibility.
• The source oscillator creating the sine wave in your synth could be mathematically incorrect. The VSTi 'Curve' by cableguys is known to have this problem, among other synths. This causes faint harmonics to be generated along with the fundamental meaning it is not a true sine wave, which you will be seeing in your Frquency analyzer.
• There's a small chance the analyzer it's self might have an issue.

The point being that no, there shouldn't be any 'phantom harmonics' in a 'normal' sine wave. If you're seeing harmonics it is down to human error; and understand that a sine wave is a theoretical mathematical function, which is expressed often quite imperfectly at front end. The important thing to understand though, in terms developing an understanding of the nature of sound, is that a sine wave should always be 'pure'. A singular vibration at a specific frequency.

Also do cutoff filters alter the source on both sides? What I mean is that it's common knowledge that a low pass filter attenuates the frequencies above the cutoff point, but does it boost the frequencies below the cutoff point as well?

Read this

How do you guys feel about using square waves for basses? It could make a bass you could feel and hear, right?

Squares for basses work well

[SunkLo]

I don't know if I'd really consider that phase cancellation in the same way that I would a duplicate of a wave, phase shifted by some amount. Technically there is a deformation of the wave caused by the phase of the additive wave, so that sort of fits the bill. But then you'd have to consider any sound apart from a pure sine to be phase cancelling itself. It's not gonna sound bad in the way a conventional phase cancelled sound will.

Phantom harmonics could be caused by oscillator aliasing or spectrogram imprecision.

[Turnipish_Thoughts]

I don't know if I'd really consider that phase cancellation in the same way that I would a duplicate of a wave, phase shifted by some amount. Technically there is a deformation of the wave caused by the phase of the additive wave, so that sort of fits the bill. But then you'd have to consider any sound apart from a pure sine to be phase cancelling itself. It's not gonna sound bad in the way a conventional phase cancelled sound will.

Phantom harmonics could be caused by oscillator aliasing or spectrogram imprecision.

Well yeah you're right any sound (apart from a single sine wave vibrating in isolation) is essentially the sum of a stack of sine waves at different frequencies and amplitudes phase canceling and boosting(?) each other.

2 identical complex waves out of phase would cause a deeper form of cancellation as the 'sum of each sum' would be generating huge amplitude peaks and troughs and otherwise upsetting the pleasing linearity of a "humming" sound wave, which is i'm sure what you're talking about. Yeah this is conventionally phase cancellation, though theoretically there's no difference between that and my previous explanation it's just the latter works on a much more macroscopic, musical level. octaves playing chordally are still resulting in a sum that involves cancellation because of the additive nature of sound. That's the whole basis of harmony from a scientific perspective, cancellation, where, say the tonic and the fifth (basic power chord) share a frequency of 3:5 and create a new wave summing the two interacting waves. That wave (perceived as a chord) has it's nature purely due to cancellation/addition and is actually just a more complex wave than a fundamental, or another wave sitting on a harmonic of that fundamental heard separately. We hear them as two separate notes (chordally) because our minds spectrally deconstruct the sound in to it's constituent peaks within the audible spectrum; that is a psychoacoustic concern, the sound wave underlying the chord is actually a single wave.

Still, I feel it was important to get across a true representation of what phase cancellation was in my op. I did that with a pretty clinical breakdown of his example because I thought it was the most relevant way to get the information across. Teach a man to fish and all that.

But yeah, you're not wrong, there was just a bit more purpose in my reply other than simply answering his question. Nothing exists in isolation

[GenericNameHere]

Not quite right. They don't have any harmonics. That's the definition of a 'sine' - 'wave'. A sinusoidal oscillation, in this case one existing in the audible frequency domain. It describes the nature of the fluctuation in the pressure coefficient of the medium (air in this case). In layman terms it is a singular vibration. Any harmonics would be separate vibrations adding to the sum. In practice, that would be separate sine waves stacking above (and/or below) the fundamental frequency.

Again, not quite right. 2 sine waves with the same phase running at the same frequency would cause no cancellation. In your case though the 2 octave discrepancy would cause cancellation, as the standing waves are fluctuating at different absolute frequencies. This would lead to a difference in the position of the amplitude peaks of each wave along the time axis, leading to cancellation in the sum.

I get what you're saying. You're talking about all the waves combining to form a sound/song, whereas I never "saw" the sounds combining to form a whole. I only saw the parts ... Until now.

So when you say this it's kind of difficult to give you a proper response because you're actively disregarding the correct answer. Everything is both never, and always in isolation, in as much as even things seemingly whole can be broken down in to their constituent parts. And in this respect sound, as built from pure sine waves, do always theoretically exist in isolation; yet are also part of a sum that is never purely sinusoidal in nature. This is the nature of sound and it simply is something you're going to have to become accustomed with (theorizing over it's make-up in terms of isolated, interacting parts) if you wish to master the subject.

I get it. You mean like how all waves are just a collection of sin waves of that are related (harmonics??) and have different amplitudes. Having just discovered additive synthesis, I feel a little like Alice tumbling through the rabbit hole.

Squares, and sawtooths are made of sine waves ... Mind = blown!!!

Using a filter on a sine wave is the same as moving the amplitude fader on your mixer, a filter attenuates or boosts the frequencies at a given point on the spectrum... The point being that no, there shouldn't be any 'phantom harmonics' in a 'normal' sine wave. If you're seeing harmonics it is down to human error; and understand that a sine wave is a theoretical mathematical function, which is expressed often quite imperfectly at front end. The important thing to understand though, in terms developing an understanding of the nature of sound, is that a sine wave should always be 'pure'. A singular vibration at a specific frequency.

I didn't know what to call "those things" I saw on the graphic EQ. Turns out it was just the sine wave being amplified by the LPF's. All this new terminology ... is new to me; sorry for being confusing.

Read this


Not more of those. They make my head hurt, but I guess I could take a gander at them again, seeing as it has the exact same "wisdom" the Synthesis Cookbook has, but only more detailed.

Squares for basses work well

Everybody loves bass.

Thanks for taking the time to write that it was really ... long ... I mean, informative -- the parts I could take in (believe me, I tried. )

[Turnipish_Thoughts]

I get it. You mean like how all waves are just a collection of sin waves of that are related (harmonics??) and have different amplitudes. Having just discovered additive synthesis, I feel a little like Alice tumbling through the rabbit hole.

Squares, and sawtooths are made of sine waves ... Mind = blown!!!

Yeah man. This is one of those mind blowing epiphanies that irreversibly alters the relationship with your intellectual perception of hearing things. Everything is made from sine waves. Well It again isn't quite that simple (lol) because sound isn't actually made from sine waves. It is in fact always a whole, but can be handily broken down in to it's spectral components, which exist as super-positioned copies of the fundamental sine wave sitting at harmonics of the sound... or sometimes not, sounds with a more noisy nature have spectral peaks that specifically don't sit at harmonic intervals. This is why they're perceived as 'noisy', think of a cymbal or snare as opposed to a piano or flute. The confusing thing is that each sound is actually simultaneously an indivisible whole that is perceived as a unique sound with it's own signature timbre and amplitude envelope; and a series of many many sine waves stacked upon each other, summing the 'master' wave we perceive aurally. Breaking that sound down into each of its component sine waves, starting at the fundamental, and listening to each wave singularly, would be like reading one line in a book. Adding them together one at a time and you could hear each little component distinctly, while hearing it as part of the growing whole. Until eventually you have added all sine waves of the sound proper back together and you have your original sound, which is essentially all those pure tones sitting at different frequencies, at different amplitudes. It is the same as looking at the sky, or over a vista, you see the whole, but you are simultaneously looking at each individual tonal shift, hue, shade and colour gradient individually, that combine in a specific way to create the image. Sound is exactly the same.

The fundamental point here is that at it's most elementary component sound always exists as a smoothly iterating oscillation in the pressure coefficient of air; millions of these happening simultaneously will translate in to any given sound in existence. It's like how different atoms built from different elementary particles create different elements, that further combine in to materials that make-up all physical things in nature. The same applies for this small area of the energy spectrum we perceive as sound; it's most elementary component is plotted as a pressure state change, that is smooth. It is inescapably sinusoidal because to be any different would be breaking the laws of physics. Nothing can quantum leap from one state change to another (unless in the quantum domain but that's too much of a digression here to justify!) and so a smoothly iterating state change, oscillating between positive and negative pressure states either side of a given neutral is what causes the air pressure compression <-> rarefaction that hits our ears at a given speed, which we perceive as a tone. 440Hz for example is the A above middle C. It will always sound the pitch that it is because it is a specific frequency, a specific speed of pressure disturbance. That speed is a pitch, another speed is another pitch, and so on.

So say when you're looking at a song's wave file on soundcloud, or in your daw. The shape of that wave is actually the sum of all the sounds playing on top of each other, causing phase cancellation/addition. If you were to zoom right in to that wave and look closer, you'd see a load of little wiggles and bumps. These are simply the quieter, higher pitched elements (smaller, quicker sinewaves) that give a pure tone it's timbre and it's over all tonic character as a sound. They are expressed as little bumps and wiggles on the wave file, because the thing you're listening to is actually a 'master wave' that's been summed from all of those sound waves playing at the same time. They sum in to one while retaining their individual character somewhat.

See this is where mixing come in to play. Because say if you have a really quiet sound playing in the same frequency range as a louder sound, the quieter sound will become increasingly harder to hear, the louder the louder sound becomes, until the louder sound has drowned out the quieter sound. This is known as auditory masking, and something that, if you listen closely to two things playing together, you will notice clearly. Playing a piano, then play that same lick over a pad thats sitting in a similar frequency register as the lick. It'll be slightly less clear, because the piano and the pad will be combining slightly into a new and unique timbre. On a physical level, the two sounds waves will be adding to, and canceling each other out, creating the new, slightly different sound, you're hearing. Think of mixing paints i suppose.


I wouldn't worry too much about all the terminology, it's something you'll pick up over time. The thing is. Making music doesn't actually necessitate learning all this stuff. It helps, sure. But it's not something that you would fail without. Sound design will of course help greatly from this knowledge, especially things like additive synthesis, and generally controlling sound from a design perspective. But being 'musical' also requires another set of tools from a completely different area of study! I suppose all the stuff I've been going on about is stuff you pick up along the way as your relationship with sound deepens, as a producer of music.

As for the stuff you've had trouble understanding, feel free to copy-pasta bits in to a reply and I'll break it down further if you want.

[GenericNameHere]

Cool. Will do, but first, I'm gonna brush up on some theory, I don't want to come of as n00bish again with my talk of "phantom harmonics." I'm on the eight Synth Secrets article; they're really informative ... but they take forever to get to actual synthesis, tho. Can't wait to start making my own snares and shit in a couple weeks, thanks to this knowledge. xD