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Equalizing for dummies!
tranceplant
PostPosted: 20 November 2006 - 20:34:56 (899)  Reply with quote
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Equalizing for dummies!
by Christian Zechner
REVISION 2 (JANUARY 26TH 2010)
This document can also be downloaded from my website (click).

OK, so you have worked for hours, days, weeks on this GREAT track of yours but no matter what you do, it just sounds flat or «muddy», you can't get the kick drum to stand out, the vocals are almost impossible to interpret and it doesn't sound as clean, transparent and punchy as you hoped it would. Here I've tried to provide an interesting and useful read about the sound frequency spectrum in general, equalizers, filters and how to utilize these in your mix.

Contents:
1. Introduction – the sound frequency spectrum
2. Music and frequency ranges – Equalizing
3. What is an equalizer?
4. Filter types
5. General frequency ranges
6. Helpful tips


1. Introduction – the sound frequency spectrum
What is a frequency? If an audio signal has a frequency of 50 Hertz (50 Hz) this tells us that the signal in question is cycling from its starting point (0) to positive amplitude to negative amplitude and back to the starting point 50 times per second. The lower the frequency is, the slower the signal will oscillate. (In synthesizers, oscillators with very low frequency settings are used as control parameters to control other aspects of a sound. These oscillators are called Low Frequency Oscillators or LFOs.)

The optimal human ear picks up sound in the frequency range of 16 Hz to 24.000 Hz (24 kHz), but the average infant/adolescent person can hear sounds between 20 Hz to 20 kHz and the range for adults are generally 50 Hz to 16 kHz. This will gradually get narrower as you grow older. Some of you have probably heard of a popular cell phone ringtone called "mosquito" which exploits this fact. It's a very high-frequent sound and cannot be heard by most adults, so it is a very popular ringtone used in classrooms, for example. The upper limit of human hearing is caused by the middle ear acting as a low-pass (LP) filter. Research shows that if ultrasound is fed directly to the skull bone, much higher frequencies can be heard (<200 kHz).

The infrasonic spectrum consists of sounds that have a frequency too low to be picked up by the human ear. This is everything between 0.001Hz up to approximately 20 Hz. These sounds can often be felt physically, but not heard. These are very energy-loaded sounds, and they can travel great distances (after the great volcanic eruption of Krakatoa in the 19th century, infrasound travelled seven times around the globe) and through/around objects with ease. Earthquake- and tornado-warning systems and nuclear bomb monitoring systems listens for infrasound, utilizing the infrasonic spectrum.

Natural examples of infrasound are: sounds emitted during and prior to a volcanic eruption or earthquake, avalanches, ocean waves, tornadoes and other winds. It is also the preferred communication method between elephants, giraffes, alligators, rhinos and whales. Animals are thought to pick up infrasound prior to and during natural disasters; this is thought to be the case in 2004 when the great tsunami hit the shores of countries around the Indian Sea. The animals fled from the shores long before the tsunami hit.

Infrasound is also sometimes utilized in soundtracks and music, as it can produce feelings of fear, sorrow and anxiety when (unconsciously) detected by humans.

The ultrasonic spectrum, however, consists of the sounds with a frequency too high to be heard by the human ear (i.e. > 20 kHz). We've all seen how ultrasound is utilized in medical situations when examining internal organs is part of determining diagnose, or to see the foetus inside a pregnant womb. Ultrasound is also used in dog whistles (16 – 22 kHz) as dogs have a higher upper limit of hearing, and in sonar/echo locators on boats. Natural occurrences of ultrasound can be found in the natural sonar used by whales and dolphins and the echolocation method used by bats when navigating and hunting in the dark.

2. Music and frequency ranges
In music, we will most of the time utilize the sonic range of 20 Hz to 20.000 Hz (most often written as 20 kHz, or sometimes only 20 k). We want to filter out any frequencies we can't hear to make room for and exploit those we can hear.

3. What is an equalizer?
An equalizer can be explained as a volume control. But unlike a normal volume control (like the big knob on your stereo system), an equalizer can be assigned to raise or lower the volume of a specific frequency rather than changing the overall volume. There are two types of equalizers, graphical and parametric. Parametric equalizers have a graphic preview of the EQ slope which most of the time can be directly tweaked by clicking on it, and you can assign any frequency and any bandwidth (also known as the «Q factor») to each band. Graphical equalizers on the other hand, have already assigned frequencies and bandwidths on each band and are therefore generally less controllable.

4. Filter types
A filter is, as the name suggests, a method used for filtering out various frequencies. They are not as advanced and versatile as an equalizer, but the principles are the same. When you are working with an equalizer you can sometimes set various filter settings on different bands, most commonly on the lowest (left-most) and highest (right-most) frequency bands. This depends on what equalizer you are using. We have seven different types of filters, all of which can be used when doing only slight equalizing or as an effect. Different filter processors/plug-ins will sound different, so experiment and find one that suits your taste. The filters are the following:

Low-Pass (LP, also known as High-Cut)
A low-pass filter will let through the frequencies below the set cutoff frequency. This is the most commonly used filter type in electronic music, mainly as an effect. Electronic low-pass filters are used in subwoofers and other speakers, to filter out the higher frequencies that can't be translated well by the respective speaker. A low-pass filter can also be useful as a simple EQ on bass sounds or for filtering out noise from bad recordings.

High-Pass (HP, also known as Low-Cut)
This is (you guessed it!) the opposite of a low-pass filter. A high-pass filter will let through all the frequencies above the chosen cutoff frequency. This is useful as a simple EQ on hi-hats/cymbals and other percussive drum sounds as well as for reducing or removing the lower frequencies in other non-bass instruments.

Band-Pass (BP)
A band-pass filter will let through the frequencies on and around the selected cutoff frequency. Band-pass filters are nice for percussive sounds and supporting/secondary bass-lines.

Band-Reject
(also referred to as a Band-Stop or Notch filter. A notch filter has a generally high Q factor)
Being the opposite of a band-pass filter, this will filter out the frequencies on and around the set cutoff frequency.

Peak
A peak filter is very similar to a band-reject filter, but in opposition to a band-reject filter, a peak filter allows you to boost or cut on and around the specified frequency, rather than just cut.

Low- and High Shelf
Shelving filters are useful when you want to boost/cut every frequency below (low shelf) or above (high shelf) a certain frequency.

We also have the Comb filter (which are essentially several peak filters) and the Formant filter (two or more band-pass/peak filters on preset frequencies. This is more used as an effect rather than EQ so I will not cover it here).

5. General frequency ranges
Play with your favourite equalizer plug-in and try out these various EQ settings. The following frequency range descriptions are meant to be used only as guidelines and are not to be followed literally!

16 Hz – 60 Hz = Sub Bass
This is the super low-end that can be felt physically by your body on a good subwoofer/sub-bass system. Sounds with these frequencies are the most powerful ones, and they will take up a lot of room in the mix. Use this range to fatten up your kick drums or sub-bass patches. Too much volume in this range makes your mix sound «muddy».

60 Hz – 250 Hz = Bass
This is where bass-lines and kick drums have their most important sounds. A common problem is that the bass-line and kick cancel each other out due to phase problems (easily demonstrated when DJ-ing, if you play two tracks and have them perfectly beat-matched, it's important to cut one of the tracks' bass level or else the kick drums will cancel each other out and the overall bass level is lowered). A useful trick then is to try phase inversion on either the bass-line or the kick drum, compressing the kick and bass together and/or avoiding placing a bass note on top of a kick drum. This range should also be lowered in most other sounds like guitars, synth-lines and vocals so they don't interfere with the kick and bass-line. Too much volume here makes the mix sound «boomy».

200 Hz – 400 Hz
Too much volume here will cause vocals to sound muddy and unclear. Cut this to thin out drum parts like snares, hi-hats, percussions and cymbals, boost to make them sound warmer or more «woody».

250 Hz – 2 kHz = Low Mid or Mid-Lo
Most instruments have their «darkest» parts here; guitars, piano, synth-lines. Boosting around 500 Hz – 1 kHz can sound «horn-like» while boosting 1 kHz – 2 kHz can sound metallic.

400 Hz – 800 Hz
You can reduce some of these frequencies on the master mix to make your overall bass level sound tighter. Boost or cut here to fatten up or thin out the low end of guitars, synth-lines and vocals.

800 Hz – 1 kHz
Here you can also fatten up vocals and make them sound warmer, in a different way than the previously mentioned method. Boosting around 1 kHz helps add to the «knocking» sound of a kick drum.

1 kHz – 3 kHz
This is the edgy part of a sound, boost (gently!) here to define guitars, pianos, vocals and add clarity to bass-lines. Cut here to remove painful mid-frequencies in vocals. This frequency range is very hard on the ears, so be careful not adding too much volume here!

2 kHz – 4 kHz = High Mid or Mid-Hi
Vocals have a lot of sound in this area, the sounds «B», «M» and «V» have their most distinct frequencies here.

3 kHz – 6 kHz = Presence
Plucky, fingered guitars and bass-lines can be more defined by boosting in this range. Cut in the lower part to remove the hard sound of vocals. Cut in the upper part to soften/round off sounds, and boost to add more clarity or presence to a sound. Boosting here helps defining most instruments and vocals.

6 kHz – 10 kHz = High
Boost this area to add more air and transparency to a sound. Crispness and sparkle can be added by boosting this range on guitars, strings and synth sounds. Snares and bass-drums also benefit from boosting in this area. In vocals, cut some of these frequencies (a de-esser plug-in does this easily by compressing this frequency area) to remove the hissing sounds. The sounds «S» and «T» lies between 6 kHz and 8 kHz and too much volume there will make the vocals stressful on your ears.

10 kHz – 16 kHz = High
This frequency range is where the crispness and brightness of sounds lie, and hi-hats and cymbals are the dominant drum parts. You can boost here to add even more air and transparency to sounds, and cut here to remove noise and hissing sounds which is unwanted in for example a bass-line. Pads and atmospheric sounds benefit from a boost in this range as well, to make them sound brighter. Be careful not to boost too heavily, or else the mix will sound noisy.

6. Helpful tips
A rule of thumb is to remove unwanted frequencies before raising the levels of those you want, but remember: the more frequencies you raise in a sound, the harder it is to place in the mix!

90% of the time it's better to cut, rather than boost frequencies in a sound.

When listening for a bad, sharp frequency (maybe your newly recorded fat guitar riff, or the beautiful vocal hook is really hard on the ears when listening on loud volume) a good tip to find that horrible frequency is to put on a peak filter with a very narrow bandwidth, high gain settings, and then sweep the peak filter across the frequency spectrum until you find the right spot where it sounds like knives are being stabbed in your ears (be careful with the speaker volume when doing this!). Now invert your gain settings to a minimum and cut this frequency. You can also increase the bandwidth a bit if it still sounds sharp. Another way is to apply a narrow peak filter, and start with the gain all the way down (instead of raising it) and sweep it across the spectrum until your instrument sits nicely in the mix.

It is really important to listen to the channel you are working on in both solo mode and together with the rest of the track. If it sounds weird in solo mode, it doesn't necessarily sound weird when played together with all the other tracks, so use your ears!

Assigning each instrument to its own frequency range will help making the mix sound clearer overall (e.g. bass-lines to the low end, guitars to mid-lo and/or mid-hi, vocals to mid-hi/high frequencies).

You cannot modify a frequency in recorded audio if the frequency isn't present in the sound itself, so if you for example have a «muddy» recording to start off with, removing frequencies can help making it sound clearer.

Removal of subsonic rumble from your mix is essential for getting a nice, transparent sound image (especially when you are mastering for a vinyl record. When writing audio data to a vinyl record, too much information applied will write a wide ridge in the record and the needle will get unstable and skip.) The application of a high-pass filter will fix this. Set it to cut everything below 20 Hz – 50 Hz.

In general, the EQ slope on a master mix should look much like a «smile». Raise the bass and treble levels and/or cut the mid range. This will ensure a good low end while maintaining a good, clear treble and the mix won't be too hard on your ears.

And lastly: if it's not broken, don't fix it!

I hope this was a useful lesson, please don't hesitate to ask if you want more tutorials/information on music production! I'll try to do some more stuff in the future if you've found this helpful.

(DISCLAIMER: This text is based on my own way and my own methods of working with equalizers, and it is not necessarily the right way to do it. Factual errors could occur in this text. Trial and error is, by no doubt, the best way of learning. This text is subject to change without notice.)



REFERENCES:
Wikipedia
About.com
Computer Music
Digital Recording Techniques


Last edited by tranceplant on 06 February 2010 - 22:29:33 (978); edited 3 times in total

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cbr
PostPosted: 20 November 2006 - 22:31:06 (979)  Reply with quote
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This is really good! Very comprehensive. I vote that it be stickied.

A couple things though: first off, parametric equalizers DO let you set the frequency and bandwidth (c.f. Wikipedia), that's why they're called parametric because they have parameters, lol. Also, it maybe isn't necessary but you could explain the difference between two-pole, four-pole, etc. filters, and when to use them.

But overall this is great, well researched and excellent info for people new to EQing. Thanks for taking the time!
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djlindo
PostPosted: 20 November 2006 - 23:06:00 (004)  Reply with quote
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Quick, easily available, and quite informative for those new to eqing. Thanks for the post. I also vote for it to be stickied cool
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Idonotlikebroccoli
PostPosted: 20 November 2006 - 23:52:44 (036)  Reply with quote
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I also vote this to be a sticky. I would love to see more tutorials of this quality; outstanding work cheers

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PlasticSoul83
PostPosted: 20 November 2006 - 23:54:56 (038)  Reply with quote
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+1, sticky it.

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spliph
PostPosted: 21 November 2006 - 00:08:18 (047)  Reply with quote
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this is so hot, thanks mate! i've learned a whole bunch already..now finally my tracks will sound better ( i hope) cheers
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spliph oh yeah
DanSunshineDahl
PostPosted: 21 November 2006 - 00:42:39 (071)  Reply with quote
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Though I feel that I'm pretty good at EQ, this thread should indeed be a:
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micra_power
PostPosted: 21 November 2006 - 01:19:35 (096)  Reply with quote
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I think I'll make this one all sticky.

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tranceplant
PostPosted: 21 November 2006 - 01:29:46 (104)  Reply with quote
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cbr wrote:
This is really good! Very comprehensive. I vote that it be stickied.

A couple things though: first off, parametric equalizers DO let you set the frequency and bandwidth (c.f. Wikipedia), that's why they're called parametric because they have parameters, lol. Also, it maybe isn't necessary but you could explain the difference between two-pole, four-pole, etc. filters, and when to use them.

But overall this is great, well researched and excellent info for people new to EQing. Thanks for taking the time!


haha you're right, i confused the two together. thanks for pointing out happy

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CosTeLLo
PostPosted: 21 November 2006 - 01:34:06 (107)  Reply with quote
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nice guide. emphasis on guide :P
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tranceplant
PostPosted: 21 November 2006 - 01:39:41 (110)  Reply with quote
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micra_power wrote:
I think I'll make this one all sticky.


thanks

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xxx
PostPosted: 19 December 2006 - 00:41:26 (070)  Reply with quote
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Thanks for this nice tutorial.

Though I have one more question concerning the whole EQ-thing. I mean, everything sounds ok if I read this, but how can I actually use this knowledge? FOr example you say 60-250 hz is bass. So should I now try to shape the curve of my Eq so that only these frequencies are "on" (or the other way round: cut the other frequencies) in order not to let the "unimportant" frequencies of the bass steal room for other instruments? Did I get this right? Does it principally mean, that when I got a nice sounding bass sound, the character of this bass in this case lies within this specific frequency range?

And what exactly means "cutting" the frequencies. Does this mean cutting down to 0 db or only a little bit?

Thanks!
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tranceplant
PostPosted: 19 December 2006 - 02:56:58 (164)  Reply with quote
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xxx wrote:
FOr example you say 60-250 hz is bass. So should I now try to shape the curve of my Eq so that only these frequencies are "on" (or the other way round: cut the other frequencies) in order not to let the "unimportant" frequencies of the bass steal room for other instruments?


the latter. a bass sound can also have higher frequencies which are part of the overall sound. f.ex. in plucked strings on a bass guitar. and if you don't cut these low frequencies in other sounds, like perhaps vocals, acoustic guitars, FX, whatever it is that shouldn't be important in the bass groove, they will muck it up alot in the bass levels making the master mix sound muddy and undefined as well as introducing potential phase problems with the bassline/kick.

xxx wrote:
And what exactly means "cutting" the frequencies. Does this mean cutting down to 0 db or only a little bit?


cutting = attenuating, removing, lowering. the opposite of adding, boosting, raising. whether you remove a little bit or everything, that's up to you and depends on the circumstances of the particular sound and the particular sound you aim for in the particular mix.

happy

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pwnstar
PostPosted: 19 December 2006 - 10:38:01 (484)  Reply with quote
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Nice thread.

Too bad your other thread wasn't worthy a sticky, although I think it's a very useful thread too.

http://trance.nu/v3/forums/viewtopic.php?t=132161

tranceplant wrote:
Compression, gating and limiting for dummies!
by Christian Zechner

2nd part of my informative music production essays.

Contents:
Compression
What is a compressor?
Why use compression?
Compressor features
Multiband vs overall compression

Gating
When and where to use gating
Gate features
Gating as an effect

Limiting
Introduction to limiting
Loudness or dynamics?

Summary
Disclaimer



COMPRESSION

WHAT IS A COMPRESSOR?
You've all probably heard about compressors and how essential they are in music production. But what do they do, exactly? Compression is used heavily in all kinds of music production and broadcasting (radio, TV...). Why is everyone talking about it? Well, I'll tell you why! You can think of a compressor as your little best friend who takes care of super-fast volume automation in your tracks so you won't have to worry about it too much yourself.

WHY USE COMPRESSION?
...you ask. In (almost) all kinds of sound, there are volume differences during the amount of time the sound endures. Our ears are much better at noticing the average volume level during a specified time (called RMS or Root (of) Mean (of) Squares in mathematical situations, but this is more science-related so I won't elaborate on it) rather than the peak level (the sound's loudest point in a specified amount of time). For example during a sentence uttered by a person. The sentence may seem like it has the same, constant volume level, or there may be only slight volume changes between the words. In reality, every single letter has it's own volume level. For example, compare the sounds M and T. Or K and U. Notice the difference? The sounds M and U are soft, not-hard-on-the-ears sounds, and they are uttered with a small, constant exhalation. But the K and T are powerful sounds, uttered with an explosive exhalation. These will stand out very clearly in a vocal recording, raising the peak level of the entire recording. You can easily see this for yourself if you own a microphone, just record a small sentence and look at the waveform afterwards. Where are the peaks? Most likely on the words that include the sounds K, P and T, because these are the most powerful sounds. Try putting your sentence into a track with many different instruments. Can you hear every word clearly? Or what if you have already normalized your recording up to just below the clipping point, and you STILL have to raise the volume in order to hear the softer sounds? This is when we call our little friend nextdoor, the compressor.

COMPRESSOR FEATURES
As it is an automated volume control, a compressor's settings have to be tweaked in order to make it act just like you want it to. Now visualize a volume slider. We want to change the settings in order to make this slider go down when you want it to. How far, when, the delay before it goes down, how fast, and for how long it should stay down before going back up to its initial value: all of these settings can be tweaked in a compressor. We also have a (makeup) gain control available to raise the average volume, in case your compression lowers the general volume of the sound. We have two different compression methods, those are PEAK compression and RMS compression. The first one is better used on sounds where the volume differences are easily noticed and relatively far apart in time (like vocals, percussions, acoustic guitars etc.) whereas the latter is best used on more noisy sounds where the volume differences are too close to each other to be noticed by the human ear (noise fx, winds, sustained guitars, strings etc.)

The THRESHOLD control is the first controller we'll talk about. This decides when and where the gain reduction is to take place. You will notice that its maximum value is always 0. Say what? 0 is zero, nothing? But in digital audio terminology, this is the absolute apex value of any sound's volume, and it is called the DIGITAL zero. When played through digital devices, any sound exceeding this limit will clip, and we certainly don't want that to happen. What the threshold controller does, is to let the compressor know WHEN to kick in. If you set the value to -20dB, the compressor will take care of every peak that exceeds -20dB.

The RATIO knob controls the I/O (input/output) level ratio of the sound exceeding the previously set threshold. If the input level is 10 dB above the threshold and the ratio is 4:1, the output level will be (10 divided by 4) 2.5 dB. If the input level is 15 dB and the ratio is 5:1, the output level will be 3 dB. When working with ratios up to 10:1, you are compressing, and ratios above 10:1 is the domain of limiters, which is explained later in this essay. (This is a general definition, and different musicians/engineers will have different opinions.)

The ATTACK and RELEASE controls are there so you can control the volume slider's swiftness. So, an attack value set to 5 ms means that when the sound exceeds the threshold, it takes 5 ms before the gain reduction kicks in. The release control does the same thing, only backwards. If the release is 10 ms, it takes 10 ms before the volume slider goes back up to its initial value.

We also have a KNEE option which decides whether the gain reduction should happen instantly or if it should be faded in, after the attack time. A SOFT knee setting makes the gain reduction fade in, and with a HARD knee setting the reduction is instant.

MULTIBAND VS OVERALL COMPRESSION
A multiband compressor does exactly the same as the above, but with one of these, you can have different compression settings on different frequency areas. Multiband compressors are best used on f.ex. master mixes or drumloops, because these have sounds in almost every part of the frequency spectrum, thus you'll want to have different settings for the bass-, mid- and the high frequencies to keep them sounding dynamic to some degree.

GATING

WHEN AND WHERE TO USE GATING
Gating is also an automated volume control, as is both compression and limiting. Gating is used when you have a recorded, dynamic sound, but you only need the loudest parts of it. F.ex., a vocal recording. Unless you record the vocals in a 100% silent room (which is pretty much unachievable), you WILL have background noise in your recording, and this is especially audible in the pauses between the words of the vocal take. This noise isn't something we need, so we can use a NOISE GATE to exclude it. Think of a gate as (yep, exactly) a gate! Our 2 friends Vocal and B.G. Noise comes along, minding their own business. Vocal passes through the gate easily, but when B.G. Noise tries to pass through, the gate closes before him.

GATE FEATURES
Being automatic, the gate needs some information from us before it can act the right way and let the right parts of the audio file pass through. We tell it to open up when the sound is louder than a certain threshold, and to stay closed when the sound isn't loud enough. We specify this by tweaking the threshold controller. A gate threshold set to -20dB will allow everything above -20 dB to pass, and exclude everything below. We also have attack and release controls, similar to those in a compressor. The attack value decides how fast the gate should open, and the release value decides how fast it should close. Some gates also have a TRIGGER FREQUENCY RANGE which allows to select in what parts of the frequency spectrum the gate should be active.

GATING AS AN EFFECT
You can achieve pretty cool effects by using a gate on pads, vocals etc.. Gates suitable for this kind of effect have a new controller in addition to those mentioned above, namely a PATTERN. Here you can draw in when and where (in f.ex. 1/8, 1/16, 1/32 notes) during a specified amount of beats the gate is activated.

Gating can also help to enhance the SNAP of any sound, especially useful when used on drums (snares with a long sustain or release, long kicks).

LIMITING

INTRODUCTION TO LIMITING
A limiter is essentially a compressor with relatively high ratio settings (>10:1) and generally fast attack/release values. Limiters are mostly useful on final mixdowns to cut the peaks of the mix, and raise the general volume without the mix clipping.

A limiter's controls are THRESHOLD, CEILING and RELEASE. Again, the threshold decides when the effect should activate. So a threshold of -10 dB allows the limiter to work with every peak above this threshold, and leaving everything else alone. A new control introduced to us here is the ceiling control. This allows you to set the absolute peak value of the sound.

Generally speaking, the ceiling should never be more than -0.2 dB to ensure that the audio data does not clip during playback in any digital media devices. This is because different speaker systems use different conversion methods from digital to analog audio (converting digital audio data to physical sound), and sometimes this conversion process will lead to the peak values being increased (due to technological and mathematical processing which alters the audio data). Setting the ceiling value to -0.2 dB is a rule of thumb, to give the audio file some headroom so clipping won't occur when listening to the digital audio through a CD player, for instance.

Audio limiting should always be the very last thing to do in the audio engineering process.

LOUDNESS VS DYNAMICS
Any use of limiting WILL decrease the dynamics in a mix. The amount of dynamics is important in music, so don't go all crazy on the limiter use. A new phenomena encountered since the introduction of CDs is often referred to as the loudness war, where audio engineers and producers use heavy limiting in order to make the music on a CD sound as loud as possible, so their CDs can sound louder than those of competing record labels. This kills a lot of the musical dynamics. But after all, it is a matter of taste whether you want your music to sound loud rather than keeping it dynamic.

SUMMARY
A common, and mostly correct, routing method between the processing units covered in this essay are as following:

1. (Noise) gate
2. Compression
3. Limiting

Compressors, gates and limiters are all essential tools in audio processing. Too heavy use will, as with all other effects, ruin your sound, so be careful and use your ears when working with these. I hope you've found this text interesting and useful for your own production and engineering methods!

DISCLAIMER
Everything in this text is based on my own knowledge of audio processing and my own ways of audio-/music production and engineering. Factual errors could occur. This text is subject to change without notice. In other words: if your music still sucks, don't blame me grin

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xxx
PostPosted: 19 December 2006 - 11:57:08 (539)  Reply with quote
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tranceplant wrote:
xxx wrote:
FOr example you say 60-250 hz is bass. So should I now try to shape the curve of my Eq so that only these frequencies are "on" (or the other way round: cut the other frequencies) in order not to let the "unimportant" frequencies of the bass steal room for other instruments?


the latter. a bass sound can also have higher frequencies which are part of the overall sound. f.ex. in plucked strings on a bass guitar. and if you don't cut these low frequencies in other sounds, like perhaps vocals, acoustic guitars, FX, whatever it is that shouldn't be important in the bass groove, they will muck it up alot in the bass levels making the master mix sound muddy and undefined as well as introducing potential phase problems with the bassline/kick.

xxx wrote:
And what exactly means "cutting" the frequencies. Does this mean cutting down to 0 db or only a little bit?


cutting = attenuating, removing, lowering. the opposite of adding, boosting, raising. whether you remove a little bit or everything, that's up to you and depends on the circumstances of the particular sound and the particular sound you aim for in the particular mix.

happy


Thank you very much for your help. So generally, if I got i right, it is at least a good starting point to work with a parametric Eq and just shape the curve a little bit into the direction it "should" be (we know: actually everything is allowed as long as it sounds good....).
Do you think one of those prgorams that analyze graphically the frequency spectrum of a sound is helpful, for example to figure out in which field two sounds interact too strongly with each other?
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