The compressor in the sound module: How to use it properly! - Part 2
Get more out of your sound: Learn to master the compressor and create impactful kits!
You can achieve fantastic sounds with the compressor. Here, step by step, you will learn what you need to consider.
Table of Contents
- How do I adjust the compressor?
- Bonus Knowledge: Order of Effects
- The Compressor's Reduction Display
- What order should I follow when adjusting the compressor?
- What ratio should I choose for adjusting an individual instrument?
- What attack should I choose for adjusting an individual instrument?
- What release time should I choose for adjusting an individual instrument?
- Bonus Knowledge: Pump Effect
- What make-up gain should I choose for adjusting an individual instrument?
- Bonus Knowledge: Volume and Loudness
- What's better - Individual Compression or Bus Compression?
- Some Guidelines for Working with the Compressor
- What should I consider when using a limiter?
How do I adjust the compressor?
First, you should familiarize yourself with the compressor in your drum module. Which controls are actually available? Is there only one compressor for the entire kit, or one for each instrument? Sometimes, the compressor is also part of a range of effects from which you have to choose.
To achieve a natural sound, you need to be careful not to turn the controls too much. The interaction of the settings is important for the result.
As often is the case, there are no fixed rules, but certain approaches have proven to be effective. They are a good starting point for fine-tuning and experimentation.
Bonus Knowledge: Just like musicians, photographers, drivers, etc., audio engineers also have a lot to talk about. This certainly applies to effect devices like compressors, which have their celebrities, secret weapons for specific instruments, and rare gems.
The order of the effects used also plays a role. A signal that has been cleaned up with an equalizer beforehand will certainly harmonize better with the compressor than an untreated signal.
Unfortunately, with your drum module, you have to assume that these nuances are not taken into account. The effects themselves will be of a more rudimentary nature.
Therefore, it will be very helpful for you to develop a sense of how the effects in your drum module work over time. This way, you will soon know what will work well and what won't.
The Compressor's Reduction Display
It's great if you have it! It functions like a reverse volume display. You can read how strongly the compressor is applied. The reduction is indicated in dB.
By the way, a somewhat consistent reduction value is a good reference point for adjusting the make-up gain control. If you reduce by x dB, it makes sense to increase the make-up gain by x dB accordingly.
Assuming a good signal level before it enters the compressor is important. If it's too quiet, the compressor may not engage at all. On the other hand, if it's too loud, you may only be able to control it with a high ratio, but that can significantly alter the sound.
What order should I follow when adjusting the compressor?
The result of compression is a combination of all the controls. Therefore, there is no clear rule for the order of adjustment. Instead, you will approach the desired result in several steps.
Depending on whether you want to fine-tune or heavily process the sound, different orders or initial values of the controls may be more sensible.
However, it's a good idea to initially turn the threshold control all the way up. This means that the compressor would theoretically only engage when the maximum volume is reached. In practice, it means that the compressor won't come into play at all.
Now you can start by setting the remaining controls to moderate values. Then slowly lower the threshold and observe how the sound changes.
If you have a compressor available for each instrument, keep in mind that the compressed signals will add up. This can quickly lead to the entire kit being overly compressed.
Especially in the beginning, when you're not yet familiar with your compressor, make subtle adjustments - even though a compressed signal often leaves a good impression that calls for even more good impression.
So, release the threshold control as soon as you notice an audible but only slight change in the sound. Now focus on the other controls.
What ratio should I choose for adjusting an individual instrument?
As mentioned before, there is no standard recipe. However, based on experience, a good starting point is to set a ratio of 4:1.
For individual instruments, it may be useful to adjust more extreme values from this ratio. For overall signals, more subtle values are often chosen.
What attack setting should I choose for adjusting an individual instrument?
There is no golden rule for that either. The attack time is usually a matter of milliseconds in the single or double-digit range.
If your signal is long enough, such as a resonating tom, you can distinguish between the transient and the decay. The transient contains the percussive strike sound of the stick.
This means that you can emphasize the transient by adjusting the attack setting. Start with a value of zero and increase it slowly. You will notice that the sound of the tom becomes progressively sharper. Adjust it according to your preference.
For very short signals like the snare drum, you need to listen very attentively.
What release time should I choose for adjusting an individual instrument?
The release time is particularly noticeable with long tones. Especially with a strong ratio and a low threshold, the release is clearly audible when it is short. In this short time, the heavily compressed signal will return to its original level.
This can create an - usually unwanted - effect called "pumping." This effect is often heard in recording devices with automatic gain control when they are fed with loud signals.
The automatic gain control tries to prevent the recording from clipping and forcefully attenuates the loud signal. When the threshold is crossed again, you can clearly hear the extreme difference within the release time.
Bonus Knowledge: However, sometimes pumping is intentionally desired! By using it as an effect on synth bass and pads, it has become a pioneering stylistic element, particularly in genres like French House. A great example of this effect can be heard in the song "One More Time" by Daft Punk.
Start with a long release time and gradually work your way towards a shorter time. Pay close attention, especially with short signals!
What make-up gain should I choose for adjusting an individual instrument?
In theory, the make-up gain is used to restore the reduced volume caused by compression.
In practice, however, you may even decrease the value further.
This is because compression tightens the sound and increases perceived loudness.
Bonus Knowledge: Volume is a measurable quantity, while loudness is a psychoacoustic measurement that describes how the average person perceives a certain volume.
A compressed signal is therefore perceived as louder than the corresponding unprocessed signal, even if no make-up gain is applied.
This is because, as explained in the example of people in a smaller room, the signal has a reduced dynamic range after compression and needs to work with that.
What is better - individual compression or bus compression?
Ideally, you have both options available: a channel compressor for each instrument and a bus compressor for the overall mix (the entire drum kit).
With this setup, you can apply more aggressive settings to each instrument to give them more impact, and then use gentle settings on the bus compressor to glue all the instruments together.
If you only have access to channel compressors and you want to add some weight to the sound, always be careful not to overdo it.
Unlike a finished recording that you can edit to your liking later, when playing your e-drum set, you will usually want to retain a natural dynamic range.
Since the principle of the compressor is to deliver something dynamically different from what you input into the set, excessive settings can quickly become distracting.
Some rules of thumb for using a compressor
If you're feeling overwhelmed and confused, don't panic. It's completely normal when working with a compressor for the first time.
Just start over and keep these important relationships in mind:
- Moderate settings are used to enhance the signal, while extreme settings can drastically alter the sound. It can be either cool or terrible.
- If the threshold is set high, you can choose a stronger ratio. The higher the threshold, the smaller the portion of the signal that will be affected. In this case, a higher ratio won't have a negative impact or might even be necessary to achieve a noticeable result.
- Conversely, if the threshold is set low, indicating that the signal is being compressed at a relatively low volume, the ratio should be low as well.
- The release time is particularly noticeable with longer signals. This is evident in bus compression scenarios where multiple signals are being constantly sent to the compressor together.
- Start with a longer release time and gradually shorten it while listening carefully.
- If the signal becomes too dense, it may lead to distortion!
- Tip: To experiment with more extreme settings and sound shaping using the compressor, choose a sound that serves as an effect sound on your kit, such as an electronic percussion sound.
What should I consider when using a limiter?
The limiter effect can be adjusted using the channel compressor. The key feature here is the ratio of Infinity:1.
This means that when the threshold is reached, the signal will not exceed a certain level of loudness.
This allows you to prevent the entire signal from clipping. For example, if you set the threshold to -1 dB, the signal will never go louder than -1 dB.
Bonus Knowledge: In the digital world, the maximum level is reached at 0 dB. When this value is exceeded, it can result in unpleasant digital artifacts.
This is different from the analog world, where it was common to moderately overdrive signals because it would naturally introduce a slight compression that would blend the sound nicely.
In the context of tape machines, this is referred to as tape saturation. It was only when you went too far that the signal would distort unattractively.
In the past ten to twenty years, in the pursuit of a louder signal, increasingly aggressive limiter settings were applied. This practice became infamous under the term Loudness War. Eventually, it went too far, and the dynamics of practically every commercial production were completely squashed.
Fortunately, the industry has moved away from the Loudness War. And that's a good thing.
The threshold is a crucial control on the limiter. You can set the limiting level to a value other than -1 dB!
This allows you to effectively compress the sound. Experiment with it and don't forget to adjust the makeup gain to maintain the desired loudness.
If you set the threshold too low, there won't be enough room for the different levels of the signal to breathe. You'll hear it clearly because the signal will sound distorted.
For special sound effects, this can be cool. So don't hesitate to try extreme settings on the limiter as a channel limiter. You might create a fantastic effect sound!
The compressor is an essential audio tool. It can make your sound more powerful or drastically transform it. As a beginner, you'll need to experiment a lot since all the controls interact with each other.
Take the time to get to know the compressor in your drum module. It can be the magical tool that takes your drum sound to new heights.
The effort is definitely worth it! Once you've learned the principles, they will stick with you, just like riding a bike or swimming.
Have fun with your enhanced drum sound!