How do I increase the volume of a low volume audio file?
What is a Low Volume Audio File?
A low volume audio file refers to an audio recording where the amplitude or loudness is lower than normal. This results in the audio sounding quiet, muffled or hard to hear at normal listening volumes (source).
There are a few common causes of low volume audio files:
- The audio was recorded at too low of a level, resulting in a low signal-to-noise ratio.
- The audio file format uses lossy compression that discards quieter audio signals (e.g. low bitrate MP3s).
- The master volume level was reduced too much when mixing and editing the audio.
- There is a peak volume limiter reducing the overall loudness.
Trying to listen to audio files with inadequate volume levels can have several impacts:
- It strains the ears and sounds unclear, especially in noisy environments.
- Quieter details become difficult or impossible to hear.
- The overall listening experience is diminished without sufficient loudness.
- Volume must be turned up very high, potentially damaging equipment or hearing.
Check Audio File Format
Different audio formats have different volume capabilities. The first step is to identify the audio format of your low volume file. Some common formats include WAV, MP3, AAC, FLAC, AIFF, etc. You can check the file extension or open the file in an audio program to see the format.
Once you know the format, do some research on if that particular format tends to naturally have lower volumes compared to other formats. For example, MP3 files use “lossy” compression which can result in lower volumes compared to uncompressed formats like WAV or AIFF. Compressed formats like MP3 sacrifice some fidelity and volume for smaller file sizes.
So identifying the audio format is an important first step. If it’s an inherently lower volume format, you may get better results converting to a higher quality uncompressed format before trying to increase the gain. The format limits how much you can boost the volume, so starting with an uncompressed source will give you more headroom.
Adjust Volume in Audio Software
The easiest way to increase the volume of an audio file is to open it in audio editing software like Audacity and use built-in volume increasing effects.
In Audacity, open the low volume audio file. Highlight or select the portion of audio that needs increased volume. Then navigate to Effect > Amplify and choose a dB level to amplify the audio by. Start with small amplifications like +3dB and preview the results. Increase the dB level gradually until the desired volume is reached. Going above +12dB can introduce distortion.
The Normalize effect in Audacity can also boost volume more subtly. It analyzes the peak amplitude and brings up lower sections to match that level. This avoids drastic variances in volume.
Other audio editing software like GarageBand, Adobe Audition, Reaper or Ocenaudio have similar volume increasing effects and tools as well. Experiment with amplify and normalize to bring up the volume without distortion or quality loss.
Sources:
https://www.sweetwater.com/sweetcare/articles/how-to-edit-audio-in-audacity/
Use Volume Booster Software
Certain dedicated volume booster software programs can be used to significantly amplify the volume of quiet audio files. These programs work by applying audio processing effects like compression, normalization, and limiting to increase the perceived loudness without distorting the audio.
Some popular free options include FxSound, Letasoft Sound Booster, and Chrome Volume Booster. These programs install a system-wide sound booster that can amplify volume across various applications. They provide sliders and settings to adjust the volume boost level.
While these volume boosters can raise quiet audio to audible levels, caution should be used to avoid over-boosting. Excessive amplification can introduce clipping, crackling artifacts and distortion. The ideal level is just enough of a volume boost to make the audio sufficiently loud without compromising quality.
Volume booster software works best for minor volume increases. For very quiet files, a dedicated audio editor with more advanced mastering tools may be required to optimize the volume without degradation.
Adjust Computer Volume Settings
One way to increase the volume of a low audio file is by adjusting the computer’s volume settings. This involves turning up the system volume as well as the volume within your audio player software.
To increase system volume, go to the Sound control panel in Windows or System Preferences on Mac. Drag the volume slider to the maximum safe level for your speakers or headphones. Just be cautious not to set it so high that you damage the speakers – going above around 80% volume could risk this.
You can also increase the volume within your audio player software, like iTunes, VLC media player, etc. Look for a volume slider in the player and drag it up towards the top. Again, don’t set this so high that you distort or damage your headphones when listening.
Combining both the system volume and audio player volume can significantly boost a low audio file. Just be careful not to push things too far at the risk of damaging your equipment.1
Use a Physical Volume Amplifier
One way to increase the volume of a low audio file is by using an inline volume amplifier. These are external hardware devices that can be connected to your audio playback system to amplify quiet signals. There are compact amplifier options like the Compact Amplifier With External Volume Control that allow you to adjust volume with a remote control.
To connect an inline amplifier, you will need an amplifier unit and speaker wires. The amplifier can be connected between your audio source and speakers. Speaker wires then run from the source into the amplifier, and from the amplifier to the speakers. This allows the amplifier to boost the volume of the signal before it reaches your speakers.
The pros of using a hardware volume amplifier are that they provide consistent volume boosting across all your audio playback, require no software installation, and introduce minimal distortion if high quality components are used. The downsides are that they can be more expensive than software options, introduce some analog signal degradation, require manual installation, and are less portable if you want volume boosting across different devices.
Convert to a Higher Volume Format
Another option is to convert your low volume audio file to a format that supports higher volume capacity. Some audio formats like WAV and lossless FLAC have a higher dynamic range and can encode louder volumes than lossy formats like MP3 and AAC.
Converting to a lossless format like FLAC or WAV from a lossy format like MP3 can potentially increase the volume output. However, this also increases file size. If file size is a concern, converting to a lossy format but at a higher bitrate can help increase volume while limiting file size growth. For example, converting a 128kbps MP3 to a 320kbps MP3 may provide a volume boost.
When converting formats strictly for increasing volume, it’s ideal to use the same codec, like MP3 to MP3 or AAC to AAC, as converting across lossy codecs can cause quality loss. It’s also important to weigh the tradeoffs of increased file size and ensure the louder volume required can’t just be achieved through amplification of the original file.
Overall, converting to a higher volume format can work but requires more storage space. It also doesn’t always increase volume substantially compared to simply using amplification tools on the original audio. Consider format conversion an option if the audio is highly compressed and other methods don’t sufficiently boost loudness. For small volume increases, amplifying the source file may be preferable.
Adjust Audio Normalization
Audio normalization is the process of adjusting the overall volume level of an audio recording so that it reaches a target loudness. The goal is to make the volume consistent across multiple audio tracks. Normalization increases the volume of quieter sections and reduces the volume of louder sections [1].
There are many audio editing software tools that can apply normalization, such as Ableton Live, Audacity, Logic Pro, and Reaper. These tools analyze the peaks and valleys in the audio waveform to determine the amount of gain adjustment needed. The standard target level for normalization is between -14 and -12 dBFS, which is considered an average listening volume [2].
When used properly, normalization can help balance out inconsistent volume levels in a mix or compilation. However, over-normalizing runs the risk of clipping or distorting the audio if pushed too far. It’s generally better to apply subtle normalization of only a few dB gain to avoid flatten dynamics or ruining transients [3].
[1] https://emastered.com/blog/audio-normalization
[2] https://blog.landr.com/audio-normalization/
[3] https://www.homebrewaudio.com/24032/audio-normalization-care/
Remaster the Audio
Remastering the original audio file can help significantly increase the volume and loudness. The full audio remastering process involves importing the original audio into digital audio workstation software like iZotope RX, Audacity, or Logic Pro. The audio is then professionally edited and enhanced through techniques like:
- Noise reduction to minimize background noise
- Equalization to adjust bass, midrange, treble
- Compression to control dynamic range
- Limiting to increase overall volume
- Normalizing loudness across the audio
A full remaster by an experienced audio engineer can breathe new life into an older low volume recording and make it commercially competitive. However, it involves more specialized skills and software. For a simple volume boost, try the easier methods first before considering a full remaster which requires more effort and cost.
When to Seek Professional Help
There are certain scenarios where trying to increase low audio volume yourself can fall short or even make the problem worse. This is when it’s best to seek help from audio professionals with access to high-end tools and years of expertise.
Professional tools like iZotope RX have advanced algorithms that can restore and reconstruct degraded audio in ways that basic editing software cannot. Audio engineers are trained to hear nuances in recordings and know how to get the best results.
Consider seeking professional help if DIY methods leave audible artifacts, distortion, or noise. Professionals may better salvage old, damaged, or extremely low quality recordings. They can also properly master the audio to increased levels without clipping or pumping.
The two main types of professionals to contact are:
- Audio restoration specialists – They focus on repairing damaged audio and improving sound quality.
- Mastering engineers – They specialize in processing/optimizing audio for loudness and clarity.
While professional services cost more, they save time and provide quality results. For irreplaceable audio or commercial projects, the expense is often worth it. Be sure to research and vet any provider before hiring them.