Essential audio effects explained for the beginner

The “Essential audio effects explained for the beginner guide” will show you the fabulous range of effects available with a DAW and how you can best use them creatively in your music.

Audio effects are processes applied to sounds to alter them. This can be to correct them, alter them or enhance them or all three. There are many different audio effects.

Some started as unwanted side effects like distortion, some were discovered accidentally, allegedly flanging, and some are to recreate natural effects such as echo and reverberation. Audio effects produce amazing transformations of otherwise bland or plain sounds, so now here’s the explanation and round-up.

I’ll also explain the differences between insert effects and send and returns effects along with what wet and dry signals actually mean.

Equalisation or EQ

Sounds are made up of audio frequencies of all sorts and complexities. Furthermore, you can see the complexities of sounds on something like an audio spectrometer.

Generally, the audio range is between about 20 Hz and 20 kHz. Most people won’t be able to hear anything at either end. Especially as you get older when your high-frequency hearing declines.

EQ gives you control over these frequencies. We’ve all used and know what simple tone controls like treble and bass sound like but there’s a lot more to that with EQ. You can use it to correct sounds, maybe there are resonant frequencies that need to be cut. If you haven’t used a pop shield you may have some pops and plosive sounds in the vocal track that need removing.

While on the subject of vocals here’s an off-the-wall way of recording them that works surprisingly well!

You can boost frequencies in sounds. Maybe give that bass drum a boost to make it boom. The more control you have over EQ the better you can get sounds to sit in the mix, subsequently making it sound better.

Graphic Equalisation or EQ

Most people have heard the term graphic EQ. They used to be all the rage in HiFi and car audio years ago. Probably because HiFi and car audio were so bad in those days.

Whereas tone controls just gave you control over bass and treble a graphic EQ gave you control over lots more. The graphic part is due to the fact that there were sliding controls placed in a row the left-hand one was the lowest frequency and the right-hand one the highest.

These sliding controls could cut or boost a certain set frequency. The number of sliders varied with cost and complexity. The more sliders the more precise the control. If you started with them all in a central position you’d get a flattish response.

You could lower or raise each frequency and you’d get a sort of picture because of the sliders. This is where the term graphic comes from.

Parametric Equalisation or EQ

This type of EQ gives you control over the frequency. With the old bass and treble, they were set. With parametric, you can set the frequency you want and then boost or cut it.

Most parametric EQs can alter the “Q” which effectively alters the width or band of the frequency being affected. I used to have an old two-band stereo parametric EQ but these days with DAWS it’s not unusual to have EQ where you can call up 8 bands if you need them.

This is only scratching the surface of EQ there are a lot more details and information to learn about EQ and using it.

Dynamic processing

Why do we need dynamic processing? Surely we can all alter the volume of audio easily enough?

This was a question that buzzed around my head as a beginner. As soon as you get involved in the practical side of sound, you’ll understand why dynamic processing is important. Dynamic processing is more to do with correcting and recording rather than augmenting sounds like reverb.

Audio Compression

I didn’t really get compression when I first started playing around with one. It didn’t really make the sounds that much different. I was too used to reverb and chorus. That’s not to say compression doesn’t have a “sound”.

You can use it to make drums more “punchy”, for instance. Compression really comes into its own when you use it in conjunction with other sounds. Compression helps some sounds sit better in a mix. Vocals are the obvious here.

An uncompressed vocal is almost impossible to sit properly in a track with lots of other stuff going on. There will be sections where it sounds too loud and sections where it sounds too low. You can manually use the fader to bring it up and down, and this is still a way to help and I still do it.

Especially now it’s so easy to automate and it means you don’t have to compress the hell out of an audio source, but applying some compression certainly helps. Basically, compression turns down the peaks or highs in level. This means that you can turn up the level without it distorting.

There are lots of different types of compressors. The way they operate can be very different so this is a just basic operation guide.

Input gain

This alters the input level. This is important as it works in conjunction with the threshold control.

Threshold

This is the basic control in which you set the level that compression operates. Below this level nothing gets compressed. Above it, compression happens. Simple. This is why it works in conjunction with the input gain. If you have the threshold set too high and the input gain too low the signal won’t reach a high enough level to be compressed.

Compression ratio

This control sets how much it gets compressed. It starts at a ratio of 1:1, which is no compression. As you increase this control the audio gets more compressed until you reach the maximum infinity setting where it limits. This is where no matter how much more the input increases, the output won’t get any louder.

Attack and decay controls

The attack sets the time before the compression effect starts and the decay is how long it takes to end. Using these controls on drum tracks can make that classic “punch” drum track.

The gain reduction meter

This meter shows you how much the compressor is working. No lights and it’s not doing anything. The more lights and the more its compresses the signal.

Output gain

This turns up the output level. You may need this to increase the output level as the compression reduces the peaks in the signal and squashes the range.

More information about using compression

Compression can be one of the harder effects to master. if you are just starting out. You may find it easier to follow some standard settings and then experiment. You can get these in my Beginners audio compressor settings chart.

Once you get used to the basics, you might want to move on to how to sidechain compressors. This is a technique well worth learning. used properly you can transform your mixes and make them sound “professional”. It opens up all sorts of ways to automatically and rapidly change volume levels. I’d go as far as saying almost every mix uses side-chaining today, certainly every dance mix!

If you want some tips on using compression on vocals then have a read here for explanations of what you need to do. From then you can progress to more advanced techniques such as parallel compression.

Finally, don’t forget that there are many different types of compressors, and each has its own sound and strength. If you are looking to “glue” elements of a mix together, then check out my using a glue compressor guide.

De – Esser

This is a specific processor designed for one job and that’s to reduce sibilance sounds picked up by a microphone in the recording of vocals. Sibilance is the sound that gets produced particularly when the “S” or “Sh” sound is made.

It can be quite distracting and some vocalists produce it more than others. Setting the de-Esser is a bit of a balancing act as it can be with a lot of audio effects and if you get it wrong you can produce more harm than good. Use too much and the vocal just sounds wrong.

If you haven’t got a de-esser you can create a similar effect by splitting the vocal track and feeding it into a compressor and into an equaliser and the output of that into the sidechain of the compressor. You set the EQ to just let the high-frequency sound through and this operates the compressor when those sibilance sounds occur.

Dynamic expansion

Dynamic expansion is the opposite of compression, but there are occasions when you use both on a track! I bet that’s puzzled some. It did me but now you understand compression ill explain expansion and you see why both can be essential. It’s all to do with levels and setting them correctly.

Noise gates

The biggest use of dynamic expansion is noise gates. Years ago these were one of my favourite audio effects. Probably because in those days we were all battling against the hiss of tape. Gates are still used today though but more through creativity than correction.

A noise gate is like a switch. It opens and closes to let audio through. It can be opened by a manual trigger. To reduce background noise it opens automatically. Whereas with compression you set the level that compression operates above with a noise gate you set the floor. Below this level, the gate stay shut. Above it and it opens. To reduce tape hiss you set the floor to be just above the hiss level. When a sound louder than this occurs the gate opens. You generally use it on one track at a time. I use it on vocal tracks to get rid of any background sounds.

With a noise gate, you set the hold time and a release time. These are to set the time that the gate stays open once the signal falls below the threshold setting. These controls can all be tweaked to either unobtrusively work on a track or use it to produce more noticeable effects. We’ve all heard the classic gatted drum sound.

Distortion

The popular distortion effect came about more by accident than intentional design. Guitarists found out that by turning their instrument amplifiers up to a maximum not only did the sound get louder but it distorted. This is quite a complex subject as to what exactly happens but to simplify it as the waveforms clipped extra harmonics were introduced to the sound. Now these extra harmonics can be extremely different depending on what equipment and circuit produces them.

Harsh distortion can be quite unpleasant on some sounds but a softer overdriven sound can bring an ordinary sound to life. You could write a complete article on the complexity of distortion, valve distortion even and odd harmonics etc but this is just an introduction.

Guitars were the first instruments to benefit from distortion but there are plenty of other sounds that come to life with a bit of dirt. Drums and vocals have all benefitted from distortion over the years on plenty of recordings. I remember reading that the band’s orchestral manoeuvres in the dark used to mike up instrument amplifiers from their synthesisers instead of just connecting them to the desk for this very reason.

There are hundreds of different distortion units. These go from effects peddles to some quite complex VST for DAWs. If you are interested in this particular effect and I would definitely advise you to explore it. My two favourites are the PSP vintage warmer and the Camel Audio Camelphat plugin.

Harmonic distortion

The distortion effect has become a very important part of digital processing and recording. Partly this is because of how pristine and clear audio recordings have become due to the progress of technology but precision sound doesn’t always mean the best sound. In my opinion, digital recording is brilliant and having a processor to recreate things like distortion and tape effects give you the best of both worlds.

You are not stuck with it like we all were in the old days and you can choose to be as subtle or otherwise as you want. Interestingly you can get distortions with my two favourite plugins that are almost imperceptible to hear but you notice when they are turned off. It can be so subtle but makes a big difference to the overall sound to improve it. even if you can’t quite tell what it is that’s happening. Harmonic dostion subtle adds harmonics to the signal.

Delay effects

These effects all have one thing in common. They use delay in some form to produce them. The delay happens naturally in audio. As sound is heard you can also hear a delayed version of it as it bounces around certain places. This is the familiar echo.

Time delay and echo

If you delay a sound, you can hear the sound followed by the delayed sound. This delay can usually be synchronised with the tempo of the music so it fits in. Long delays of over half a second can usually be perceived as separate sounds.

In a real environment, you don’t just hear one delay. The delayed sound can bounce back and you hear a delay of the delay at a lower volume and so on until it’s too quiet. This can be simulated with a delay line. You just feed some of the delayed signals back to the input. This is the feedback setting. Using longer delays timed with the music and plenty of feedback can give you some mighty impressive sounds, undoubtedly rhythmic!

As you shorten the delay time it gets harder to perceive the delayed sound as it merges with the original. You can hear delays of 20 ms to 100 ms as almost a doubling of the sound.

Double tracking and chorus

As I mentioned above short delays produce a sound that is sometimes called double tracking as it can sound like two instruments playing the same thing. If you modulate the delay time you produce a chorusing effect.

A low-frequency oscillator similar to vibrato rates, modulates the delay time and you have a simple chorus. You can usually change the rate and depth of the modulation. Increasing these emphasize the effect. Have three delay lines and modulate them with different low-frequency oscillators and you can have a simple single sound huge. Chorus can be used on most sounds.

It’s especially useful on melodic sounds. Synthesizers, guitars and vocals can all benefit from this effect, especially in stereo where it can make a sound even bigger. I used to have a Boss CE3 stereo chorus pedal and I used it on nearly everthing!

Flanging and phasing

When you have two identical sounds you can cancel certain frequencies. If you have a short delay it simulates two sounds and frequency cancelling occurs. By modulating the delay time these cancellations occur at different frequencies and this is the popular “whooshing” phasing effect of the phaser. Phasing is often used on keyboard sounds and it provides plenty of movement to static sounds.

The flanging effect is similar to the chorus and phasing but with feedback introduced. This feedback introduces more frequencies and resonances and produces the famous tunnelling “effect”. Again this effect can be used and probably has been used on nearly every sound produced.

Reverberation

This is another naturally occurring sound. You can hear it at its best in large cathedrals or caves. These are large spaces with very acoustically reflective surfaces like the walls, ceilings and floors. The sound gets reflected backwards and forwards repeatedly until it dies away to nothing. The larger the space the longer it takes to die. Some huge buildings have reverberation times of several seconds.

Even smaller rooms can produce reverberation if it has acoustically reflective surfaces. The bathroom usually has tiled surfaces. Reverberation adds tremendously to vocals. That’s why you sound better singing in the bathroom. Furthermore, almost every vocal recorded has some reverb of some sort added to it.

This effect has been simulated or the years with springs and plates but more recently with very clever algorithms and digital processing. The reverberation effect can vary hugely depending on how it’s set. You can have room sizes from small rooms to cavernous cathedrals. The most common controls on a reverberation effect are:

Decay time

This is the time that is takes the reverb sound to die away. Larger rooms have a naturally longer decay time.

Pre-delay

This is the time it takes for the first sound reflection to get back to your ear. Again the larger the space the longer the pre-delay time will be.

Dampening

This is the effect of the high frequencies being absorbed. If you turn up the dampening control there are fewer high frequencies in the reverb.

Diffusion

Diffusion in a room is the number of reflective surfaces. Less reflective surfaces make an effect more like a number of short echos effect. More diffusion leads to a dense reverb sound. This would be like a large room with lots of acoustic reflective surfaces.

You can add reverb to any sound and almost everything sounds better with some type of reverb on it. In reality, you hardly ever hear a sound without any reverb on it.

It’s very easy to overdo the reverb and drown a sound. There is however a technique that can help avoid this and that’s to use ducking on the reverb. You can do this either by using sidechaining and a compressor or using a reverb that has it built in. I cover a reverb that does exactly this in my article about choosing a reverb specifically for vocals.

Reverb used to be simulated with springs and plates. Digital reverb took over from these electro-mechanical devices and this has remained the case for quite a while, however, there is now a version of reverb that is becoming popular and that’s convolution reverb. This is where real environments are sampled. You can read here for more information about convolution reverb and impulse response.

Multiple effects: essential audio effects explained for the beginner

You can of course use more than one effect on a sound or track. You may have seen some of the multiple effects units or the string of guitar effect pedals that some guitarists use. It’s also worth noting that the order that the effects are put in makes a huge difference to the sounds produced.

An echoed reverberation effect is different to a reverberation effect with an echo applied to the result. There are some typical ways that effects are connected but don’t be afraid to experiment and listen to the results. With modern DAWs, you have plenty of ways to do things with effects. My advice though is not to get too carried away with the effects.

It’s all too easy to get carried away with the fantastic, huge and varied effects that can be created but that can consume a track if used too much. Especially when you are new. The idea is to use them to augment what you have recorded and make the sound better. Like most things with music, you should listen back and make considered choices

How effects are connected: insert, send and return

In the old days as a musician, you bought an effects pedal or effect unit and plugged your sound source, guitar or synthesiser into it. This is essentially an “insert” effect. You can still use an effect like this, especially if you wish to record the sound with the effect on it.

You can also take a recorded track and put an effect on the end of it in “insert” style.

Wet and dry

You may have seen these terms before. They refer to a signal. A dry signal is one that has no effect and a wet one is the affected signal. There are some effects where you just want the affected or treated signal.

You would set the reverb to 100 per cent wet. On each channel of the desk you have a number of send controls so in this example, if we had a vocal track turning the send control up would send some of the signals to the reverb unit. You would hear this from the desk returns. Things like EQ where the whole sound is processed.

Sounds you don’t want a whole affected sound and you want some of the original mixed in with it. This is the case with delay. You want some of the “Dry” sounds. In these cases, you have a mix of control of the “wet” and “dry” signals. This is often one control with 100 per cent dry at one extreme and 100 wet at the other you can then mix the effect.

Mixing desk sends and returns: essential audio effects explained for the beginner

You may have seen send and returns on mixing desks. If you were to use a reverb unit on a mixing desk you would connect the outputs from it to the returns on the mixing desk. Finally, the send output from the mixing desk would go to the inputs of the reverb unit.

The more you turned the send up the more reverb on the signal. If you had a snare drum on another channel and you turns up the sand then you would get reverb on the snare. This is how you can set different amounts of reverb for individual sounds using the same reverb unit. Each sends channel on a desk can connect to e different effect so you could have send 1 going to a reverb and send 2 going to a delay.

Final thoughts about essential audio effects explained for the beginner

The subject of audio effects is huge. There have been books and articles written on using them, sometimes in very complex ways and routings. As this is just a beginner’s guide I’ve only been able to scratch the surface of this fascinating audio subject however I’ve hopefully given you a grounding in the basics so you’ll have at least some knowledge to take forward for your own experimentations.

Also, if you have any older 32-bit effects plugins that you want to use, but can’t because you’ve moved to a 64-bit host, have a look at my article about just this subject, using 32-bit plug-ins.

This article is mainly for the creative use of different types of effects. Particularly for recording tracks and music. If you are looking to “fix” a track or recording you should be looking at audio restoration, which uses lots of other techniques and equipment.

You’re in for a treat if you’ve never heard of the Isotope RX audio tool. I can honestly say I’ve never been more blown away by an audio plug-in!