All about HPF Frequency: Helpful Beginner’s Guide

When you work with an audio production and audio mixer, you always come across this term called HPF or the High pass filter. If you are getting into audio production then, you will need to know about this filter and its mechanics.

Don't worry about that because I will help you out with it. Here, I will go through everything you should know about HPF frequency. You will also know how you can use it in your audio production and how to get value out of this.

So, without wasting any more time, let's jump right into the whole thing.

What is HPF frequency, and how does it work? 

As you already know, HPF stands for high pass filter. It's a filter that cuts off any frequencies above a particular point. Simply put, when you use this filter in your audio mixing, you can cut off certain frequencies and avoid them from having in your final audio file.

The way this filter works is pretty straightforward. You put this filter at a certain frequency, and anything below that will be cut off. You can also call it low-cut filter or bass cut filters. Because what this does is, eliminate any of the frequencies that are lower than the frequency you set for it. Anything higher than that gets a pass which gives it that name high pass filter.

Uses of high pass filter in your audio production 

You can get several uses out of a high pass filter. They are sometimes a crucial part of editing and producing your audio. Knowing about these uses is very important as you can apply that in your work as well. Let's check out the application of a high-pass filter in audio production.

• Using the high pass filter, you can simply block any kind of currents running through circuits. This helps out a lot when you are dealing with circuits that are usually prone to damage.

These circuits can hardly go through any dips or rise in the audio devices. Having the high-pass filter there releases the factor of any rise or dip in the currents.

• You can use a high-pass filter in combination with a low-pass filter to produce some high-quality sounds. You get to see this a lot in loudspeakers because they use them to cut off any disturbing noises while having a higher volume level.
• High pass filters are also used for protecting DC amplifiers from any AC coupling. Without the filter, the voice coil on the loudspeakers can produce some waste heat, impacting the amplifiers.
• Another use of a high pass filter is in omnidirectional microphones. With the use of a high-pass filter, you can impose a boost in proximity sounds for anything close to the microphone. Any microphone getting more than 500hz receives a lot of value from a high pass filter.

These are some general uses that you get to see from the high pass filter in different scenarios. It can be quite impactful and helpful for getting the most out of your audio. Now, let's get through some cases where you should use a high pass filter and where you should avoid it.

Related: How to Determine Speaker Crossover Frequency

When should you use a high-pass filter?

The best use you get from a high-pass filter is when you are using it for a microphone. Noises like the rumbling of the air-conditioner or even someone walking can be eliminated with this filter. These are low-frequency vibrations that can impact how the audio you are producing sounds.

Those lower frequencies producing such noises get cut off with the high-pass filter. And it also allows all the higher frequencies to sound even better. A high pass filter eliminates the chances of having those low frequencies in your audio right from the source. This helps you keep the audio free of any noise, even without bringing it to the preamp.

You can try using a high-pass filter when you are working with vocals, cymbals, piano, guitar, and different mid to high-frequency audios. Using the filter in these cases helps remove the unnecessary rumbling, buzzing, and humming noises from those audio samples.

So, when you are editing or mixing your music, you have an easier time with the process as you won't have to deal with those noises in the mix at all. Altogether, the best time to use a high pass filter is to use a microphone for recording purposes.

Related: Harman Curve

When should you avoid using the high-pass filter?

If you are doing a live performance and your microphone offers a high-pass filter, it's better not to use the filter. Because, in a live sound setup, your soundboard will do a far better job in eliminating all the rumbling and lower frequency noises from the audio.

Another case where you may not want to use the high pass filter is when you have some critical lower frequencies that you don't want to cut off. For example, when you are working with kick drums or bass guitars or maybe low synths, you would want to avoid using the high-pass filters. Because these instruments usually tend to have the primary sounds in the lower frequency range.

Also, you should avoid using a high-pass filter anytime you are dealing with video playback audio or backing tracks because there might be some use of a lower-end frequency in the video that you might accidentally cut off if you are not careful.

Related: good bass boost frequency

Conclusion 

All in all, if you are interested in music and want to pursue it, it's important to know about the HPF frequency. Because knowing when and where to use it will help you a lot in easing out the process of your audio production journey.

Since you plan to get into audio production, knowing about the whole is undoubtedly beneficial for you. Also, many people get confused with the whole concept of high-pass filters, which is why it's essential to know about them. Using the high pass filter correctly, you can get excellent quality out of your audio.