This is a continuation of our article on noise reduction using Reafir and Light Host. Please complete that tutorial before continuing on.
I know, a lot of this stuff looks pretty scary.
But rest assured, its not nearly as difficult as it looks. We'll go over setting up noise gates and talking about ways to reduce or eliminate keyboard noise from your mic.
Before we start, let's set some expectations. Filters and gates are not magic. You can NOT just "remove keyboard noise" without removing other parts of the audio. The goal here is to minimize its impact without causing much distortion to your voice, but you'll probably never reach a point where your keyboard is "invisible." - especially if you're out there slamming your Cherry Blue switches in a fit of rage.
What is a noise gate?
A noise gate is a type of filter that literally turns your mic off until it bypasses a certain threshold. This means if you set it up right NONE of your keyboard noise will come through, but when you talk your voice will. However, if you type and talk at the same time a noise gate will do nothing to prevent the keyboard noise from happening. Still, if you're tapping away taking notes on a call or spamming the WASD keys trying to get a frag while not talking, it's certainly nice to have.
Setting up a noise gate:
We're using Light Host as our DAW and ReaGate as our VST. So, left click on your Light Host icon and select the Cockos menu and add the reagate plugin to your chain.
Also, you want to make sure that reagate is the first item on your list, so move it up above the Reafir-standalone.
Now click the Light Host icon again and select Reagate and click "Edit" and you should be met with our terrifying image from above. Worry not, we're going to go through this line by line for the items you need to know.
The Insanity Setting:
Next up we're going to make it so we can hear our own mic. It's VERY unnerving, so don't forget to undo this change when you're done!
First, open your Sound Control Panel and right click on the Virtual Cable output in the recording devices tab. Select Properties.
Then move to the listen tab and select "Listen to device." Hit apply and say something. If you've got virtual cable set up correctly you'll now hear your voice. Insanity may ensue.
Reagate - Master Control
On the left side of your screen is the master control. Anything above that slider will activate your mic, anything below that slider will not.
Remember our insanity setting of listening to our own voice? Slide that slider all the way to the top and your mic will not activate at all! Try it!
To set this bar correctly you want to be able to hear yourself talk but NOT hear your keyboard, mouse, or anything else you want filtered. If you set the bar too high it will "clip" the first bit of your voice (or eliminate it entirely). If you set it too low you'll hear your keyboard. My personal setting for this is -20, yours may vary, but that is probably a good starting point.
Pre-Open and Attack!
Always attack! ... no wait, wrong tutorial.
Pre-open is pretty simple. It adds a delay on your mic line. In exchange, it listens to the mic first and then decides if the mic line should be open. Start with it at 20ms and increase it if you're noticing the first letters of your sentences clipping. You can even go as high as 100ms, but I believe that will be excessive.
Attack, similarly is how long it takes for the gate to open. The higher this number the more it will "fade in" your voice. Frankly, 0ms is fine here.
Hold, Release, Hysterical!
Ok fine, it's Hysteresis. Killjoys.
Hold is simple: This is the amount of time after you stop speaking that the gate stays open, allowing sound through your mic. If its too low, it will clip the end of your words. I'd set this to 20ms just like the pre-open. It's probably not needed because of the next step.
Release is like hold, but instead of instantly turning off after the time has passed, it slowly releases the gate, essentially "fading out." In many ways it is the opposite of "Attack." This is what we want to use to make our voice sound natural and not get clipped more than Hold. Set the release pretty high, I suggest 500ms to start. Set it (or hold) higher if your voice is still getting clipped off at the end. Lower it if you can, as lower is better.
Hysteresis is even more of a fade-out than Release. You can think of release slowly closing the noise gate but not adjusting the volume. Hysteresis, however, actually adjusts the volume and makes you fade away rather than cut off sharply. We don't want that, so leave it at 0.
At the end of my setup I look like this:
Last step, open a recording program and do some test recordings. Again, if the filter is cutting off your first letters, increase pre-open. Be sure to test with lots of words that have soft starts and ends, S, W, H, R, and L words are good examples.
Here are some good test words, be sure to give the mic time to reset back to being gated between each and use them at the start of end of a sentence.
Witches (Soft start and end)
Whom (Soft start and end)
Howard (Soft start)
Slither (Soft start)
Shiver (Soft start and end)
Van Gogh (Soft end)
So, something like "Witches? No, that's just Van Gogh."
If it is cutting off the end of your words, increase hold or release. If its cutting off the start, increase pre-open. Also test tapping the keys without talking. Remember, you'll still hear the keyboard if you talk while typing. A noise gate only stops noises coming through when you're quiet.
Here's the results of our hard work!