You Don't Understand EQ

this is actually the secret to mixing for modern levels of loudness the more frequencies you cut out the more headroom you gain to drive it harder into your saturators compressors and limiters frequency distribution is everything eq is probably the most important tool we have in our tool kits however i think a lot of people overlook it because it's so basic when we first start out music production eq is one of the first things we learn and for that reason i think a lot of people glance over it and don't give it enough attention as some of the other concepts in music production if you can master eq your mixes will be so much better i promise so in this tutorial i want to go really deep i want to talk exactly about what an eq is doing to the sound and then later on i'm going to give some practical advanced tips that i don't see mentioned anywhere else online now fair warning this is going to get extremely technical so if you're not into all this nerdy stuff and you just want the practical tips you can skip here [Music] what is an eq an eq change is the frequency distribution of a signal there's three main parameters there's the frequency which changes the center frequency around which the eq effects there's the gain which is how much gain is applied to that center frequency and then there's the q now the q stands for quality factor which is a term that comes from physics what it means is the ratio of the energy of a frequency to the rate at which energy is dissipated per cycle so what this means is if you have a really high q value the rate at which energy dissipates must be really small and this is why having a high q causes a sharp resonance that decays over a long time because energy is dissipated slower this also ties into the fourier transform but that deserves its own video but basically the fourier transform takes a wave that has time on its x-axis like you see in your audio software and represents it with frequency on the x-axis like you see on a spectrum analyzer that's it this is what a spectrum analyzer is doing when you hear a wave playing the waveform you see on the left and the spectrum you see on the right are the same thing just depicted differently [Music] now in this video i'm going to talk exclusively about parent pair parametric eqs and i'm just going to focus on digital eqs because honestly i don't think the digital world gets enough love you know you hear all this talk about analog this analog that where's the love for digital so in this video i'm just gonna talk about digital eqs first off you have to understand what an eq actually does if i have a sound and i eq it a new sound comes out this new sound can be thought of as the original wave convolved with something called an impulse response now what does that mean convolution is just when two waves are multiplied together as they slide past each other okay so what's an impulse response remember how the fourier transform takes a wave and represents it in terms of its frequencies the eq curve you see is the fourier transform of the impulse response put another way the impulse response is the time representation of the eq they're the exact same thing just represented in different ways so when you hear impulse response in this video you can think eq curve in your mind if that makes it easier for you it's just another way to represent it so going back to what i said earlier eq8 means convolving a sound with its impulse response so as the sound plays we slide the impulse response past the wave and multiply with the original wave as the two overlap the wave we get out is the eq'd wave you still with me it's not too late to skip to the practical stuff there are two kinds of impulse responses finite impulse responses and infinite impulse responses finite impulse responses are finite meaning that they go to zero after some amount of time whereas infinite impulse responses don't and go on forever and eq is using infinite impulse responses could potentially ring out indefinitely [Music] if an eq uses a finite impulse response the next sound that comes out is only dependent on the next sound you put in that's in contrast with an infinite impulse response where the next sound that comes out is dependent on the next sound you put in but also the previous output so there's a feedback loop involved analog eqs can be modeled using infinite impulse responses and this is because the capacitors in the eq act as a sort of memory of the state in which the filter's in finite impulse response eqs have a better stability associated with them and this can sometimes improve the frequency response of the sound because round off errors aren't accumulated inside the filter notice that i don't say improve the sound because the small imperfections can make it sound better i promise this is going somewhere there are two main kinds of vqs there's minimum phase eqs which have zero latency but introduce a phase shift then there's linear phase eqs which don't change the phase at the expense of introducing latency so no phase shift sounds great but in practice this isn't always the case linear phase eqs result in pre-ringing where transients get smeared and the sound appears to fade in before it should but why does this happen it's due to the impulse response being delayed since the left side here represents the future now the sound starts here and we can't predict what the wave is going to do in the future so we're forced to delay the impulse response so the eq can affect the wave properly and give zero phase shift so that's confusing let's look at it in a simpler way if i have a chunk of audio that's being passed into a linear phase eq and i hit play all of the sudden the wave appears and starts playing the wave can't be affected properly though since half the impulse response isn't touching it in order for the eq to work properly the wave would need to start back here before i hit the play button now as far as i know time machines don't exist so what happens instead is after i hit the play button we delay the sound from starting so that the impulse response overlaps with the wave the delay is so that the computer has a little bit of time to see the incoming wave regular eqs have impulse responses that are only positive so there's no need to introduce a delay this is also why brick wall filters are impossible if you have a perfect brick wall low pass eq the impulse response looks like this which extends infinitely far in each direction remember the x-axis of the impulse response is time so as you approach a perfect brick wall filter a signal would need to extend infinitely far in time and this is why brick wall filters are impossible without some sneaky hacks both regular and linear phase eqs cause post ringing but it's hard to perceive since it's mixed in with the original sound linear phase eqs effectively halves the post ringing and provides an equal and opposite amount of pre-ringing there are some methods you can use to reduce the amount of pre-ringing and in some cases eliminate it almost completely for bell points the amount of pre-ringing of linear phase eqs is dependent on how sharp you're cutting or boosting and the frequency you're cutting and boosting at cutting tends to cause less pre-ringing than boosting and eq'ing lower frequencies tend to reduce the duration of pre-ringing we're almost there the effective cue on pre-ringing is interesting higher q values increase the duration of the pre-ring but decrease its amplitude so to recap impulse responses on the right-hand side of the y-axis give regular minimum phase eqs whereas symmetric impulse responses give linear phase eqs side note anti-symmetric impulse responses look like this the left side is the opposite of the right side and the frequency response of this would give you an eq that changes imaginary frequency and man the rabbit hole goes pretty deep when you start looking at imaginary frequency but i digress so should you use linear phase eqs or normal eqs well like everything in music production it depends if you're eq'ing in parallel regular eqs can cause phase cancellation so linear might be the way to go now if you want that transient to hit right where it needs to minimum phase eqs would probably be better however the phase cancellation that minimum phase eq's introduce isn't necessarily a bad thing in some cases it can cause a sort of multi-band pumping effect that can sound pretty juicy if you pull it off right dan warhol has an amazing video on linear phase eqs that i highly recommend that's your homework go check out his video now i know i said i would only talk about digital eqs but i know there are some of you dirty analog purists out there so let's talk about analog for a second an analog eq is basically a digital eq with an infinite sampling rate so time is treated as a continuous quantity rather than chopped up into samples in the same way that a digital eq curve is given by the fourier transform of its impulse response an analog eq curve is given by the laplace transform of its impulse response the laplace transform is more complicated than the fourier transform but basically you can think of it as a fourier transform for a frequency distribution that changes over time and it contributes to that warm sound we hear and you might be thinking well a spectrum analyzer has a frequency distribution that changes over time and that's true and the spectrum analyzer isn't really doing a fourier transform but this video is getting way too deep and i'm going to do a video on 48 transforms and spectrum analyzers and why you can't trust them okay now that you have a conversation starter for your next date let's get into the practical stuff okay so i'm going to give you some eq tips that i don't see mentioned much elsewhere online and this really helped me up my eq game tip number one this is something that's helped me a lot and it's probably my most important eq tip it's the idea that eq cuts create definition what do i mean by that eq cuts cause separation between different parts of the spectrum and this doesn't just reduce the frequency that you cut it actually appears to make what's on either side of that frequency cut to pop out of the mix a little bit more two sounds that take up frequency regions beside each other can be made to stand out more if you just cut the frequencies between them eq cuts create space between frequency bands which sounds obvious but this gets to a really important concept in music production the way we perceive part of the frequency spectrum is dependent on what's happening around it this is one of the reasons the classic poltex style eq shelving sounds so good the small dip before the boost causes more separation between what's above and below the cut let's say you have a mix and you want 300 hertz to sound louder instead of boosting 300 hertz you can cut 200 hertz and 400 hertz and this will make 300 hertz sound louder even though it isn't and this is actually the secret to mixing for modern levels of loudness the more frequencies you cut out the more headroom you gain to drive it harder into your saturators compressors and limiters frequency distribution is everything if you look at the frequency spectrum of modern edm or hip hop or pop music that has a really strong sub bass you'll usually see a pretty big cut anywhere between 100 hertz and 400 hertz and this is because having that region empty allows you to turn the sub up extremely high while retaining clarity in the high mids and highs so you can make a sound stand out simply by taking away what you don't need i find that if i have a sound that spans the entire spectrum i can push it a little forward in the mix simply by making one or two eq cuts and then gain matching after but these cuts need to be strategically placed which brings me to my second tip understand which parts of the sound you need and which parts you don't it's tough sometimes to know how to eq a sound especially when it sounds good on its own but not good in the context of the mix there's two main frequency parts of a sound there's the fundamental and then there's the higher harmonics if you use a high pass eq and take out the fundamental and maybe the first few harmonics you'll be left with the texture of the sound but there won't be a strong tonality associated with it in general the higher up the spectrum you go the less the harmonics contribute to the actual note you perceive and more to the flavor of the sound and that's due to the fact that the harmonic series has more and more atonal tones the higher up the spectrum you go and this is exactly what timbre is these higher texture harmonics are what differentiates an e note on the guitar to an e note on the flute to an e note of the airplane flying overhead and there is a fundamental there it's just very hard to hear so by just letting the higher harmonics through you kind of isolate the flavor of the sound without there being any obvious note there and this is the most important part of layering sounds stacking different timbres on top of each other can trick your brain into thinking there's a huge unique cohesive sound but in order to do that you have to identify which parts of the sounds you need and which parts you don't one way to tell which frequencies you don't need is to play the entire thing and sweep an eq cut across if you find that cutting out a certain frequency range doesn't drastically change the timbre of the sound you can cut that sound out but it's important that you do this while you're listening to the sound in the context of the mix the only exception to this i think would be if you're trying specifically to fill up a part of the frequency spectrum but it can still be hard to fit a certain sound or instrument into your mix which brings me to my third tip boost to find where the sound should sit in your mix if you're trying to fit a sound in a mix but it's just not working try turning the sound down about 5 db below what you think it should be and take an eq and boost and just sweep around the spectrum to find where the sound should live in your mix this technique also works well for identifying empty spots in your mix if you're trying to fill it up more my last tip is something that separates the pros from the rest of us the most important thing about learning eq is listening something i've noticed about watching very experienced engineers it's as if they can hear each part of the frequency spectrum individually i like to break the spectrum up into six parts sub the base and the low mids the mids the high mids the highs and the ultra highs this is just what works for me if you have a different way of dividing up the spectrum go for it whatever floats your boat really get to know each part of the spectrum like your best buds the best way to do this is to take a song you really like throw it into your daw and just go wild with it make boosts and cuts and really listen to how it changes the balance of the mix how does the mix suffer when you boost the mids by 6 db listen to how empty the mix sounds when you cut out 2 and 300 hertz by doing this you'll build up an intuition for how different parts of the frequency spectrum contribute to a mix and how to identify problems in a mix it'll also help you figure out what your songs are lacking if it's missing something another method to really learn the lay of the land of the frequency spectrum is to take white noise and send it through a low pass filter and just slowly move it up the spectrum pick a frequency and try and stop on that frequency with your eyes closed don't cheat and try this with a high pass filter also and instead of white noise try it with a saw wave if you really want a challenge try it with an entire track when i did this i found that what i would call bassiness or muddiness starts way higher up the spectrum than i thought you might have heard that our ears are pretty sensitive to the two to three kilohertz range and that's true but i've personally found other regions that can become quite harsh in the highs and i only discovered that because of doing this exercise and eq'ing with my eyes closed i always eq with my eyes closed that's another thing you don't want to be fooled by the spectrum analyzer so eq with your eyes closed okay so these eq tips are what i have found helpful and i haven't seen them mentioned much elsewhere online if you found this video helpful hit like and subscribe i'm going to try to grow this channel with a bunch of obscure and advanced production techniques and weird little topics if you have a topic that you don't see mentioned a lot online comment it below and i'll see if i can make a video about it anyway more tutorials to come stay tuned [Music] you

Channel: sseb

Views: 355,482

Keywords: Advanced Music Production, advanced eq tips, how to EQ properly, Mastering Tips, EQ Tutorial, EQ Tips, Audio Filters, how to EQ, mixing with eq, mixing with eq tutorial, You Don't Understand EQ, Advanced eq tutorial, how do EQs work, Analog EQ, How to EQ properly, Best EQ tips, linear phase eq explained, phase shift from EQ, linear phase eq, preringing, fabfilter pro q 3, linear phase eq vs normal eq, best eq tips

Id: r7556ybtdW0

Length: 17min 40sec (1060 seconds)

Published: Sat Jan 16 2021

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[u/D3ltaT3a]

I loved this video, would love to see more from you. New like and follow :)