The “Look ahead” feature in T-De-Esser Pro makes the plug-in monitor the signal a while before it is processed. As a result, the audio plug-in will be able to respond to future level changes sooner.
Why should you use the “Lookahead”?
The “Lookahead” feature can be very useful because it makes the plug-in’s reaction much faster to respond to extremely rapid transients, even when set at lower attack time. Furthermore, very quick attack times might produce unnatural-sounding effects and distortion in certain cases. As a result, “Lookahead” allows it to obtain the smoother, more natural sound that comes with shorter attack times yet still capturing very fast transient sounds within your audio signals.
Check these two vocal examples below, to hear the difference when the “Lookahead” is enabled or disabled. (The settings are set intensely to make the effect more audible.) Both tracks have the attack at 0 ms. Enabling the “Lookahead” in this case avoids the artificial pumping effect.
How does the “Lookahead” actually work?
If the T-De-Esser Pro’s “Lookahead” is enabled, you will duplicate the signal entering it. The duplicated signal is delayed by 5 milliseconds. In the meanwhile, a side chain receives the non-delayed signal. The plug-in responds to the signal that isn’t delayed. However, de-essing is only applied to the delayed signal.
Because the signal that will be processed by the plug-in arrives a few milliseconds after the non-delayed signal has informed the plug-in what to do, it may effectively look ahead and respond to changes before they occur.
Check out these two audio examples on how disabling or enabling the “Lookahead” would affect a drum track. Both have the same settings and the “Attack” is set at 0 ms in both tracks. The settings are set intensely to make the difference more audible. You’ll notice the high-frequency sounds like hi-hat or clap that are being de-essed when the “Lookahead” is off, sound a bit distorted due to the very fast attack reaction, while in the second audio, it sounds smooth and clean.
You might be thinking to yourself at this point, “Will the track sound out of time if the signal from the de-esser is delayed?” You shouldn’t be able to hear the difference since the delay introduced to the signal is so tiny. To make up for the latency caused by plug-ins, most new DAWs have automatic delay correction built-in as well.
How does it sound in the context?
When to avoid using the “Lookahead”?
During the recording and tracking process, we recommend not keeping the “Lookahead” enabled, as it’s better to have zero latency for that.
Does the “Lookahead” affect the CPU usage?
The “Lookahead” in general does increase the amount of CPU usage, but in “T-De-Esser Pro” we optimized it so that it uses the least amount of your computer’s CPU power.
By Amin Asbaghipour – Techivation CEO