What Is Quantization In Audio?

When we record instruments into digital audio workstations, the signal is usually not accurately timed with regards to the tempo or bpm.

The reason for this is simple, human playing of instruments cannot be accurately and perfectly timed because we are not machines.

Only digitally played notes like ploting on a piano roll can pretty much assure us of some consistency in accurate timing.

Something that is closely related to this that you’ve probably come across and didn’t exactly know its meaning is something called quantization.

So you may be wondering like most people do,

What is quantization in audio?

Quantization is the act of transforming and moving notes recorded into a MIDI sequencer or DAW in line with the “grid,”  in order to make a precise performance. This enables the notes to be perfectly timed and on beat or on tempo.

It’s difficult to record notes perfectly by hand, some notes will be in time some will be mistimed which may be easily noticeable. Rather than having to record the notes again to perfection. Quantization allows you to line up and place your notes in time so that there aren’t any notes played too early or too late and hence enables the notes to be in perfect sync with tempo.

To put it in simple terms, quantization is the of act aligning notes or recorded signals so that they’re in sync with the tempo and are not off timed.

Importance of quantization

Let’s get into the importance of quantization in digital audio and why it’s such an important tool for instruments, vocals and other audio elements.

Aligning instruments

Free playing instruments by hand is always bound to stray away from tempo. This is part of human nature and is something that is only avoidable to a certain extent.

With that said, it’s always good to get your notes and instrument in line with the tempo.

In order to avoid the instrument sounding off.

Think about an instrument playing at 110bpm while the rest of the song plays at a 150bpm.

The difference will not only be noticeable but it will be unpleasant to listen to. Which is why a quantization tool comes in handy and helps us easily deal with any off timed instrument  notes.

This way, the instrument will be in perfect sync with the rest of the song.

Aligning Vocals

Vocal performances in recording are not always perfect. Sometimes it’s difficult for a musician to be on beat.

Sometimes beats or instruments can distract the person recording which would have them be off beat.

To ensure that the vocal performance is on beat using a quantization tool can be helpful.

Things like this are usually handled during the editing phase and engineers know to use this tool to get the desired result.

Quantization saves times because the artist doesn’t always have to re-record. The engineer can simply align the vocal to match the tempo and keep everything in sync.

Dealing with samples

Anybody that has ever dealt with samples knows that not all samples are perfect with regard to timing.

Therefore when trying to build a beat around a them, it can often be irritating when you they can’t match a specific tempo accurately.

Sometimes, even using a tempo detector will only get you to a rough estimate of the tempo of the sample.

In this case, applying a quantization tool can help you easily ensure that you keep the sample in perfect time thereby putting aside all timing problems.

When it’s easier to play by hand

Certain instruments cannot be easily plotted on midi. Instruments like guitars are easier to play live and by hand rather than plotting them on a piano roll.

In such situations, the use of quantization definitely comes in handy.

Knowing you can play and record your instruments and get them well timed with quantization makes things easier.

Complex compositions

When dealing with complex compositions like orchestrated music it’s very difficult to keep all instruments in timed sync with each other.

Especially in situations where a lot of instruments are played live and not plotted with midi.

Dealing with a bunch of instruments and getting them on beat can be hard but thankfully quantization can be a more than helpful tool.

When quantization may be avoided

While it may be necessary to use quantization in some cases, there are a few exceptions in which it may not be employed.

Below are the two common exceptions.

To get a natural feel

The biggest downside with quantization is that it makes everything too perfect.

While this maybe something that most audiophiles look for ….there are times when they also avoid it.

If say, you’re looking for a natural feel in instrumentation…. a live recording can be left as is without applying any quantization in order to make sound as authentic as possible.

This is a common case with most guitar solos. Quantizing them may just throw the listener off because they’d sound unnatural.

When quantization feels unnatural

When quantization feels unnatural most audiophiles will simply not apply it to instruments or vocals. Because this would make the entire song sound unusual.

This is quite often when one is dealing with samples. Sometimes you’re better off living it as it is and applying only a little bit of quantization to make it sound natural and not too forced to coincide with the tempo.

When dealing with such samples I usually use effects like delay to make the delay effect be on time in order to mask any imperfection in the timing of the sample.

Final Thoughts

Quantization is obviously something that is important and useful in digital audio processing.

However it’s important to know when to use it and know when not to.

Some instruments are better kept natural in order to have them sound normal and not too digitized.

In some cases however, quantization can be useful in getting instruments or vocals on tempo so they don’t sound completely off.