Have Questions? Join our Discord!

Removing Background Noise with Equalizer APO and Reaper's ReaFir

If you're experiencing background noise, odds are high it is either EMI, which comes across as a static hiss or a ground loop, which is a low hum in the background.

These problems come from your hardware setup, not the microphone, but fixing them is relatively easy and cheap. The easiest way is to buy a USB adapter like the one we sell.

However, there IS a free method, but it takes a little work and will slightly decrease the quality of the mic. How much? Here are some samples of the start and end of this process.

If you don't want to buy that USB you're going to need two programs, Equalizer APO and the Reaper VST plugin ReaFir.

Equalizer APO:

Reaper VST:

Make sure you download the correct version of the Reaper VST, 64 bit most likely.

Step 1: Install Equalizer APO (EQ APO)

When you install EQ APO you'll get a pop-up to select the devices you want to use. While you can select all the devices you normally use for audio (there's a lot EQ APO can do) the only one that matters for THIS tutorial is your microphone. 

As you can see in the image above, I have selected both our USB and a normal 3.5mm input, but you'll probably only want the 3.5mm input, as the USB should not require this tutorial.

Next, you'll need to reboot your machine.

Step 2: Install ReaPlugs by Reaper

Installing ReaPlugs should be as easy as running the installer. However, I like to put it into the same directory as I put EQ APO, just so I can find it easier. You may need to reboot after installing this as well. Just make sure to note where you've installed it, as that will be needed in the next step.

Step 3: Set up EQ APO

Start by running Configuration Editor in the EQ APO directory, but remove everything so you're looking at a blank slate. When you're done it will look like this:

Neat! Now we have to add only two items to the top. First, click the + sign in the top left and add Control -> Device and then click "Change" and select only the mic we want to edit.

Once you have that selected press "OK" and then click the plus sign under the Selected Device. Now add Plugins -> VST Plugins and then the load button. It's this guy:

Navigate to where you installed ReaPlugs and load the file "reafir_standalone." 

It should look like this when you're done:

Finally, press the button labeled "Open Panel." We're now ready for the final step.

Step 4: Configure ReaFir

This looks more complex than it is, so don't panic! Under "Mode" select "Subtract." It's highlighted below:

Then drag those two dots ALL the way to the bottom, so you end up with a flat line at the very bottom of the screen. It'll look like this:

At this point, you can click "OK" or "Apply" and actually go test your recording! ReaFir's subtract mode comes with a built-in noise suppression, so messing too much in this area isn't needed. However, if  your mic is too quiet simply add some mic gain on the right-hand slider marked "Output Gain." Test in increments of 5dB, keeping in mind the higher this goes the worse quality will get (but the louder your mic will be).

One thing to note: If you crank your volume WAY up you'll probably notice you traded a "hiss" for a very low "hum." For most people this is the end, the hum should not be easy to hear compared to the hiss and would only matter if you were doing real recordings.

Here's the final result:

In my tests, it is possible to remove that humming, but it will come at decreased quality, and worse, every machine will be different so I can't give you a set of magic numbers to use. However, I have included the final optional step for those who want to play around a bit with this.

Optional Step 5: Subtract Low Frequency

First, let's be clear, I do not recommend doing this. It can decrease your background noise further, but it will create weird artifacts in your voice. You probably won't hear it unless you turn the volume WAY up. For those who know how to build a real noise profile you can use that to tune your settings, but for most people, the best way is to simply reduce the amount of volume in the frequencies you hear noise. In my machine, I get a ground hum style noise at about 200hz. Your noise may be similar or totally different, but play around with the EQ and you can see what it does to your voice. Almost all the noise you should be removing is low frequency, so basically the higher your raise those red lines on the left the less bass your voice is going to have, remove too much and you'll sound like you're talking into a cheap mic, which totally defeats the purpose of using a ModMic!

Here are my settings:

And here's what it sounds like:

Again, you'll have to turn the volume way up to hear both the artifacts and the background noise difference between this and the final above. 

Previous Post Next Post