Microphone Gain Vs Volume – Differences & Similarities Between The Two 

In the world of audio recording, ‘gain’ and ‘volume’ are two aspects that are extremely important. The two have quite a substantial role to play in producing the optimal audio quality. 

As critical as the two are, they are also quite misunderstood. Both the terms are often confused and are used interchangeably. The truth is gain and volume are two separate attributes of audio signals.

When it comes to creating music, mixing, or performing it, it is important to know the two and how they affect your music. Understanding their significance, I thought to explore the two attributes and discuss the differences between them.

Gain Vs Volume- How Are The Two Different?

Simply put, gain relates to the input’s loudness whereas volume refers to the output of a sound system entirely. Let’s now dive into the two and how they are interpreted in the field of modern digital recording. 

Meaning of the Two Terms

I’ll start with discussing the definitions of the two terms so you get clarity on what they stand for.

What is Gain?

Gain refers to the attenuation or amplification of an input audio signal. This basically means that gain is used to decrease or increase an audio signal’s level. Mostly, it refers to the signal that you are recording in a mixing console.

Audio gain is the signal’s input level. It is not the signal’s final volume. In order to get a clear output signal, you would naturally want the input signal entering the mixing console is noise-free and powerful. This is where the gain control comes in handy.

You can alter an audio signal’s strength with the gain controls. This is exactly why they are also known as the input gain knobs. And since gain refers to the input signal, it is also known as the input gain.

If you increase the gain using the gain knob, you boost the audio signal. The signal automatically becomes louder. Now if you do the opposite of it, and reduce the gain, the signal will become quieter. The gain is controlled at different phases of an audio signal chain. When the signal moves from the microphone to the preamplifier to a mixing console, its gain changes.

What is Volume?

Volume refers to the dB (decibel) output of an audio signal and sound system. In simple words, it is how loud a signal is after it has undergone processing.

The quietness or loudness of an audio is its volume. In case you are mixing music, the level that you send from the channel to the stereo output is its volume.

Also referred to as loudness, volume is the perceived sound intensity generated by your headphones or speakers. It is what makes a dialogue vibrate in the headphones, or a song blast through the speakers.

Contrary to gain, volume does not deal with the signal strength. It controls the sound waves’ output levels. These waves are generated by your headphones or speakers. Whether an audio sounds quiet or loud to the human ears is determined by its volume. This is why it is also sometimes referred to as the output volume.

Purpose of Input Gain and Output Volume

The main purpose of gain is to adjust an audio signal’s strength so it becomes optimal for recording and processing. On the other hand, volume is about controlling the loudness of an audio signal during playback.

Let’s discuss these two in detail now.

Gain Adjusts Signal Strength for Recording or Processing

With the help of gain, you can ensure that a signal is optimally fit to be recorded or processed in the audio chain. It operates in the following ways in different scenarios:

• Microphone Gain: When you set up your mic for recording, you need to adjust its gain. This step makes sure that an incoming audio signal from your mic is powerful enough for your audio mixer or recording device to accurately capture it. If you increase the gain, you amplify the signal. It then becomes strong enough, and will quite likely not pick up any unwanted noise from the noise floor.
• Preamplifier Gain: Preamplifiers are used in a live sound setup or a recording studio. Their job is to amplify the instrument or microphone’s signals before sending them to the recording interface or mixing console. With the gain control knob on a preamplifier, you adjust the signal’s input level. This helps you get the optimal signal-to-noise ratio which improves the audio’s tonal characteristics.
• Processing Gain: In an analog signal processing unit or a digital audio workstation (DAW), gain controls help you control the audio signal’s amplitude during the mastering or mixing process. You can shape the overall dynamics and sound balance of the mix by decreasing or increasing the specific frequencies and tracks of the mix.

Volume Controls the Perceived Loudness of Audio During Playback

When you playback an audio through the headphones or speakers, you use the volume controls to control the audio’s perceived loudness. Volume works in the following ways in different scenarios:

• Amplifier Volume Control: In a home theater or stereo system, you use the volume controls to adjust the amplifier’s output level. This output drives your speakers. If you increase the volume, the audio playback becomes louder. If you decrease it, the audio playback becomes quieter.
• Headphone Volume Control: If you are using a laptop, audio player or smartphone, you will adjust the headphone jack’s output level with the volume controls. You can raise or lower down the volume according to your listening preference. This will not affect the primary or original audio signal.
• Software Volume Control: In a media player or digital audio app, you use the volume controls to change the stream’s or audio file’s playback volume. It modifies the audio signal’s amplitude digitally prior to sending it to the sound card for playback and any conversion. 

Effect and Application of Volume and Gain on Signal Path 

The effect of gain is on the signal’s amplitude directly. It affects its strength as well as its ability to experience any distortion.

As opposed to this, volume does not change the signal. It merely influences the intensity of the sound waves that the headphones or speakers produce.

As for the application of the two, gain modifications are done during the basic stages of an audio signal during the signal path. These are done with mic preamps or microphones.

Volume adjustments, on the other hand, take place during the output stage. As they control the sound’s loudness as reproduced by headphones or speakers, they occur at the final stage. You don’t need a microphone preamp for that purpose as required for gain adjustment.

The Job of a Gain Knob and Volume Knob 

The gain and volume knobs are quite talked about, and important too. Both of them contribute to the audio quality and how well it is controlled. Let’s discuss the individual jobs of the two.

What The Gain Knob Does

The main task of a gain knob is to control how much an audio signal is amplified. It controls the signal’s strength and makes it fit for recording, transmission or processing. Its major functions include the following:

• Amplifies the Weak Signals: With the gain knob, you can boost the poor audio signals. Instruments and microphones generally generate weak signals. By increasing the gain of a very quiet signal, it becomes more prominent and stronger. It is then optimal for recording and any processing. With optimal signals, the audio quality improves as well.
• Optimizes the Signal-to-Noise Ratio: When you properly adjust the gain, you optimize the signal-to-noise ratio. In the context of audio, the signal-to-noise ratio refers to the relationship between the amount of background noise in an audio signal, and the strength of that signal. When you appropriately boost an audio signal, you ensure that it is clearly captured. It then has minimal interference or background noise.
• Sets the Input Sensitivity: In an audio system that has many input sources like an audio interface or audio mixer, the gain knob helps set every channel’s input sensitivity. By controlling the gain, you make sure that every input signal properly matches the set criteria of the processing or recording equipment.

What The Volume Knob Does

The primary job of the volume knob is to modify the sound’s perceived loudness during the playback stage. It controls the audio output’s level from the headphones or speakers. Its key functions include the following:

• Controls Loudness: You can easily decrease or increase an audio signal’s loudness using the volume knob. If you turn the volume control clockwise, you will make the sound louder. Naturally, if you turn it anticlockwise, you will decrease the sound’s volume and it will become quieter.
• Adjusts the Listening Level: You can easily change the volume level as per your requirement and preference with the volume knob. If you are in a gathering, or in a conversation, you can lower the volume of an audio. And if you want to hear something clearly, or enjoy some music on loud, you can increase its volume.
• Prevents Distortion: If you master volume control, you can prevent distortion in audio too. When the overall output volume becomes too high, the audio waveform’s peaks become cut off. This is known as clipping and it results in harsh and distorted sound. On the other hand, a very low volume can cause a weak signal-to-noise ratio which reduces the audio’s clarity.

By now, you must be quite clear on how gain and volume are different from each other. Perhaps, there is one ambiguity left about gain staging, and whether or not there is something such as volume staging too. Let’s clarify that too.

Volume and Gain Staging- What Are These Two?

Gain staging is an important stage in audio engineering. Let’s discuss it in depth.

Understanding Gain Staging

During gain staging, you optimize an audio signal’s levels during different stages of the signal path. This is how you get the desired sound quality, and reduce noise and distortion in the signal too.

With this process, you ensure that every element in the audio signal path functions optimally. It also helps you avoid excessive and insufficient gain. The former leads to distortion and clipping, while the latter reduces the dynamic range, and increases noise.

Staging works in the following manner:

• The process starts by setting the main input gain level. It is done at the input stage or mic preamplifier stage of your recording device. You adjust the input gain which ensures that the audio signal you receive is strong enough.
• Next, you move to the processing gain stage. When the signal passes through processing stages like equalization, sound effects, and compression, you may need to adjust the gain to sustain the required signal level. Effective gain staging at this stage helps ensure that no distortion or noise seeps in any stage.
• Finally, you land on the output gain stage. At this stage, you adjust the output gain level of the audio signal. It makes sure that the output signal level fits the requirements of the other stages in the playback system or the signal chain. You set the output level of the audio interface or mixer, or a guitar amplifier if you are using a guitar. As a result, you get the required overall output volume of the entire processing system without any distortion or clipping.

Be it a live sound environment, or studio recording, gain staging helps you get clean audio recordings. Yes, you need to pay attention to detail at every stage so the gain stays optimal throughout the process.

What About Volume Staging?

There isn’t any specific term such as volume staging in audio engineering. Having said that, the way you stage gain also applies to how you can control the volume levels of a system.

Whether you are in a studio environment or a live performance, you may need to adjust each channel’s volume levels to get the suitable volume of every audio track in the entire mix. This process isn’t known as volume staging really. However, its principle is quite similar to that of gain staging as it helps optimize the volume levels to get the required balance and quality of sound. 

With that bit covered, let’s see if volume and gain share any similarities.

Similarities between Volume and Gain

Yes, volume and gain do share certain similarities too. Let’s take a look at those.

• Measurement Unit: The measurement unit of both, volume and gain is the same: decibels (dB.)
• Controlling Mechanism: You can adjust both volume and gain using digital controls, sliders or knobs on your audio equipment. They give you the option to tailor your audio experience according to your listening preference.
• Significance in Audio Engineering: Both volume and gain are quite important and useful concepts in the field of audio engineering. It is crucial to know how to properly set the gain and volume levels. With that knowledge, you can get the optimal sound quality of an audio.

Although volume and gain have their own distinct roles, they are quite interconnected. And you certainly cannot deny their importance in shaping an audio.

Conclusion

Gain is crucial for setting the basic stage to record and process an audio signal. As opposed to that, volume is responsible for delivering the final audio to your ears. 

Honestly, you need both to create the perfect audio, and one cannot exist without the other. Once you grasp the differences between gain and volume, you can practice sound manipulation quite confidently.

Frequently Asked Questions