What are Audio Pass Filters? (Complete Guide 2023)


There are many tools that are essential to music production and are necessary to get the best quality of audio possible. One of these tools is the audio pass filter, which helps attenuate the range of frequencies.

In this article, we will be explaining what an audio pass filter does and the difference between the two types of filters, low pass filters, and high pass filters.

If you are interested in music production or you want to know about the whole process then it’s vital that you understand all the purposes this tool serves since it has been used for a long time and still is, to this day, a powerful tool in the music industry.

What is an Audio Pass Filter?

An audio pass filter will attenuate a range of frequencies, this is achieved by using both high pass filters and low pass filters, the first one will let the higher frequencies through the filter and attenuate everything below a cutoff frequency, while the latter will attenuate above the cutoff frequency, letting all the lower frequencies go through the filter.

It may sound a bit confusing at first but it’s actually a straightforward process, and it gets even simpler when you know why and when to use it.

When to Use Audio Pass Filters?

As we stated before, this is a very common tool for a music producer, since it’s very useful in order to control high and low frequencies to get the perfect mix.

Removing Low or High Frequencies

If you record a bassline, you will probably get more low frequencies than if you record with your guitar, but sometimes there is too much bass in relation to the rest of the instruments, so what you would have to do is get rid of some of those lower frequencies in order to have a clearer mix.

This is where the high pass filter comes in, the idea is that you use the filter and adjust the settings in a way that you remove every frequency that is just too low for your mix.

You can adjust these settings before or after having all your tracks but if you can set it from the beginning, you might be able to get a better idea of what you want everything to sound like.

It goes the same way for higher frequencies, you would just have to use a low pass filter and you will be able to get rid of unwanted higher frequencies.


This has always been a big problem when recording music, and even in these modern times, sometimes there is no way to avoid having wind or sounds from the environment in your recording.

If you are not in a room that has been specifically made for recording and is free from any external noise, then you might want to avoid any external noise you can get, this includes fans, refrigerators, and more.

However we are aware that sometimes we can’t have any control, for example, traffic noise, dogs barking, and maybe even the wind.

In this case, a high pass filter will do the trick, as most of the time these sounds are mainly around the low frequencies.

Even if you can’t fully get rid of these unwanted sounds, you will be able to reduce their presence.

Removing Plosives

Whether you are dealing with singing or talking for podcasts, videos, or any type of voice recording, there is always the risk of plosives, these are low-frequency audio peaks that occur when a person makes a sound with letters like p, t, k, b, d, g, in which the air in the lungs is blocked by a brief moment which results in a burst of air being released that gets picked up by the microphone.

Now, before we talk about how to eliminate it, the ideal way to deal with this issue is to prevent it, with good quality microphones and better technique while speaking or singing, or even using a pop filter.

If for any reason, you have a recording with plosives and there is no other option, then you can use a high pass filter. As you keep getting rid of the lower frequencies you’ll notice that the popping sounds will start to “go away” since you are taking away the lower frequencies that make them stand out.

However, keep in mind that if you overdo it with the high pass filter, you might end up removing some of the vocal signals from the recording,

Improving the Mix


The best scenario for mixing is when you get the best recording possible, and once you have that, you get access to full-range monitors and a good room.

This will not only allow you to get a better idea about how the final product should sound but also be able to notice the little but important things in the mix you might need to correct. If you don’t have the best quality possible for mixing you might encounter some issues when playing the track such as:

  • When you play it, you notice that you prefer the sound of the mix on some devices or the car rather than others. This is the result of missing some of the frequencies and sounds while mixing, making them clearer or more distant due to the different quality of the device.
  • You find that there are instruments in your mix that aren’t equalized properly causing them to get peaks and distorting the sound. This is because of a lack of headroom optimization which is often caused by too many low frequencies.
  • Compressors are all over the place. This is a common problem in mixing that can be solved by taking away any compression from the mix and checking if the problem is with the compressor itself or maybe it’s something else.
  • When listening to the mix, there is no consistency between the mids, highs, and lows.

If you don’t have access to great headphones or speakers, the best way to get an overall understanding of the mix is to try and listen to it on every device possible (car, phone, speakers, headphones…).

Get Creative

Once you understand how to properly use low-pass filters as well as high-pass filters, you’ll be able to play around with them and use them in different ways that are not conventional or for problem-solving.

In the end, it’s also another tool you have as a producer and musician to make your ideas come true in the form of a song.

If you want a good video that briefly explains the basics of high-pass filters and low-pass filters, then you should check out the link below:



There are many basic concepts and tools that are essential for music production, however many of these are often forgotten or ignored, causing both beginners and experts to make mistakes when it comes to mixing.

This might not be the most fun part of making music, but it is a very fundamental part of what makes a song sound good.

There are many more such as this one, and if you are an aspiring musician or producer, we recommend you get the basics as clear as possible before you get to the fun part, trust us you will avoid a lot of frustration and the creative process will be a lot better.