As recording engineers or recording artists, there is a very high likelihood that you’ve encounter clipping before. Simply put, clipping is a form of audio wave destruction. It occurs when an amplifier exceeds the capabilities of its maximum load. In the analogue world, this is typically measured in voltage and occurs within the circuitry of your hardware. In the digital world, the bit-depth of your session will dictate its maximum load. Using 16-bit, we can allocate up to 32,767 positive values. Any signal that is amplified above this will be truncated and rounded down. This will lead to distortion. Any form of distortion or saturation can be attributed to audio clipping.
Whilst limiting can be considered a form of clipping, there are really only two forms of audible wave destruction. These are known as hard and soft. Hard clipping is what we typically associate with distortion. It offers loudness and aggression but also the most audible breakdown of the signal. Avoiding it is simple, don’t overload the capabilities of your system. By keeping your master fader below 0dB, you prevent digital hard clipping. Equally, by not exceeding the voltage load within your preamps, you won’t hard clip their output.
Now, this isn’t to say its something that we want to avoid at all costs. Just think, where would electric guitar tone be at today without hard clipping? Equally, it’s sometimes the exact effect you might be looking for. Being able to heavily distort a vocal for stylistic effect or destroy a drum kit for the purposes of layering and adding aggression is something many of us might want to do. The important consideration here is understanding what you’re trying to achieve. If you’re recording an orchestra, chances are you don’t want your recording levels to be anywhere near the top end of your preamps. This is going to apply lots of nasty, harmonic content that is sure to destroy your recordings.
Now, this is slightly different. Whilst it is still a form of distortion, we tend to refer to its audible phenomenon as saturation. It typically offers a far more pleasing sound, helping audio to retain punch whilst adding warmth. This is something that only happens authentically within the analogue world. However, there are plugins available on the market. These are designed to recreate the effect that soft clipping has. Avoiding this is simple. Just like with hard clipping, you just need to pay attention to how you are loading your system.
Essentially, soft clipping has more of an appeal because the transition between un-effected and effected signal is much smoother than that of hard clipping. The clipping is applied in the way that most compressors work, where we started to see it applied the closer we reach our threshold (this being the maximum load). This squashing coupled with gentle distortion can add some real weight to a recording. Using either plugins or by picking up a second-hand tape machine, you can apply soft clipping to your works. Give it a try on the focal instruments in your mix or even your entire mix bus to add some warmth.
Whilst not officially a form of clipping, limiting is still a form of voltage threshold management. Limiting is designed to avoid any form of hard or soft clip. This is achieved by creating the least distorted signal, despite how hard we push the amplification. Now, this does have its limits. Most limiter plugins will be bound by how far they can push a signal before it starts to break up. Equally, limiting will always reduce dynamic range within your audio. Being sensible with your LUFS metering will lead to appropriate usage of limiters. Also, avoiding the use of limiters as a way to make individual elements louder in your mix should be paramount. It’s always better to turn other elements down than to try to push sounds up.
Clipping occurs when we overload the capabilities of our system. Be it the voltage of your outboard preamps our the bit depth of your DAW, hard clipping recordings is generally a bad thing. Now, I say generally because it does have its uses. Electric guitar players utilise it all the time and many industrial and metal vocalists like to layer up their vocals using it. Soft clipping differs in that it is much smoother and generally more pleasing to the ear. Add this to your mix bus can add some real warmth and punch. If you’re looking for loudness without clipping you’re probably best off mastering your track through MasteringBOX. If you’ve accidentally clipped your mixdown, check out our article on how to prepare your track for mastering and learn how to avoid this issue.
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