Audio mixing revises and refines multiple tracks into the audio you hear in films, TV shows, music, and podcasts. With the great diversity of audio mixers available, it can be difficult to decide which one is right for you. To choose an audio mixer, consider your budget, desired sound quality, and the audio effects you want on your tracks.
An audio mixer is an electronic tool used to combine and mix audio. The device—also known as a sound mixer, mixing console, or mixing desk—lets you blend and adjust audio signals to create singular, compelling soundscapes.
Audio mixers are made up of several components:
Audio mixer channels are either mono or stereo. Mono signals can be recorded and played through just one channel, while stereo signals use at least two. While mono audio is duplicated across all channels, stereo audio is slightly altered to create the illusion of space—known as a stereo field—within the sound by presenting it through the left and right channels simultaneously. This is achieved by using effects such as reverb, delay, and audio dynamic range to convince the ears that the sound is localized to a tangible spot.
Channel count and I/O
The channel count is the measure of how many audio sources can be connected to a mixer’s channels. It includes recorders and microphones, as well as line-level equipment such as signal processors, amplifiers, and preamps. Even if they’re sourced through a single channel, stereo channels count as two inputs.
On top of the main channel inputs, mixers also come with input and output jacks. These are used to connect other appliances to the mixing console, including outboard gear, monitors, instruments, and headphones.
Many mixer controls are duplicated for each channel into sections called channel strips—sets of knobs and sliders used to control the audio effects of each channel. The main components commonly found on channel strips include:
- Input and outputs: Channel strips have different inputs made for different kinds of cables. For example, XLR cables are commonly used for balanced microphone and line-level signals over long distances; USB cables are typically used for connecting digital equipment and other devices, such as cameras; and ¼-inch cables are commonly used for sources such as outboard gear, headphones, and audio interfaces.
- Preamp: A preamp is a kind of amplifier designed to boost the audio signal strength of transducers—or, electronic devices that convert energy (in this case, the vibration of sound into a signal through a microphone) into different forms, making it louder. The energy transduced by microphones goes through a preamp to increase volume without adding any unwanted distortion or noise.
- Insert: The channel insert lets you detour signals as an input or output.
- Compression: The compression tool allows you to adjust the dynamic range (the difference between the softest and loudest parts of an audio signal), resulting in a smoother sound balance. Note that this isn’t the same type of compression used to change audio files.
- Gain: Also called input sensitivity, gain sensitivity, and trim, the gain function raises the signal transmitted by the recorder to match that of the mixer so it’s audible at the input level. Too much gain causes distortion and clipping, while too little results in too much noise.
- Aux sends: These are used to send a signal from a group of channels to an outside receiver such as monitors, headphones, external effects processors, or recording interfaces. If you’re creating a monitor mix meant to be heard during a recording, having enough aux sends is essential.
- Equalizer: The equalizer or EQ is used to adjust the balance of audio frequencies, measured in Hertz (Hz), within a signal—or remove them entirely. Equalizers come in a few different varieties:
- a. Parametric equalizers: Commonly found in digital mixers, parametric EQs adjust the Hz of a specific frequency within a given range, hone in or expand the bandwidth (or Q) of each frequency, and then raise or lower the decibel (dB) level.
- b. Graphics equalizers: These feature 6 to 31 sliders set to a specific band of frequency. Generally, graphics equalizers are simpler to use but less precise than parametric equalizers.
- Filters: If you want to remove certain frequencies entirely, filters are your best bet. For example, if you’re editing or mixing a dialogue track, you can set low and high-pass filters that remove sounds below or above the frequencies the human voice reaches. That way, any background noise in those frequencies won’t be audible.
- Volume faders: Faders control channel amplification output.
- Pan: Pan dictates how channel audio is distributed between the left and the right of the stereo field.
- Meters: Finally, meters visually show the audio output of each channel.
Tracks can be combined into one adjustable channel or output together as a stereo or master bus, which is then sent down the signal chain. If you’re using a mixing console and are sending a monitor mix to a stereo monitor setup or headphones, you’ll need two aux buses. When using mixing software, buses are either separate from other channels or are their own unique channel types.
Phantom power transmits DC voltage from a mixer to the preamp of a condenser microphone through a balanced cable.
This term is used to describe the level of amplitude an audio signal receives. Low-output dynamic and ribbon mics operate on a very low amount of voltage and therefore need preamps with gain to create audible sound. High-output condenser mics don’t require nearly as much gain since they come equipped with their own amplifiers.
Sound mixers are either analog or digital. The key difference between analog and digital is the way each records and processes audio signals. All audio starts in an analog format because it’s recorded with a microphone, but the recording can be saved as either analog or digital. Analog recordings have unlimited bandwidth because they represent physical sound vibrations, while digital signals are capped at a fixed bandwidth.
Here are a few of the advantages and disadvantages of analog and digital sound mixers:
Analog audio mixers
Analog sound mixing boards are the OG of the sound mixing world. Many sound engineers still use analog because of the unique color it brings to audio.
- Tactile and intuitive: If you enjoy the feel of using entirely tactile controls, analog could be the way to go. Analog is also a solid option if you’ll be performing live mixing because the controls are straightforward and easy to adjust.
- Budget-friendly: Analog mixers are usually cheaper than their digital counterparts.
- Manual: However, they may not be suited for more complicated performances and recording sessions because they can’t be programmed or automated. If you’re looking for more amplification and portability, take a look at powered mixers. They aren’t as fancy in terms of features, but they’re a good option for live performances if you don’t want to carry around additional power amplifiers.
- Limited effects: Analog mixers lack the convenience of wireless remote control and the diversity of onboard audio effects that digital has. If you want additional effects, you’ll have to link up outboard equipment. “I definitely do outboard analog equipment, some of it older, some of it newer, to get specific flavors of compression and EQ and tone-shaping, depending on the nature of the project,” says music engineer John Rodd (“Nope,” “Get Out”).
Digital audio mixers
Despite the limit on audio bandwidth due to digital modulation, digital sound mixing boards come with many benefits.
- Integrative: Digital mixers allow you to easily transfer audio files to other digital platforms and save level setups.
- No interference: You don’t need to worry about white noise interference from the circuitry when using digital mixers.
- Steep learning curve: These devices come with a vast array of options, which can be a double-edged sword since the interface can get cluttered and take longer to navigate.
- Easy storage: Digital mixers come as sound mixing boards or software programs called digital audio workstations (DAWs). When using a DAW, you’re spared from making extra room for a console since everything will just be stored on your computer. You can also attach a digital rack mixer that lets you input multiple channels.
- Multiple effects: One of the biggest benefits that come with digital mixers is the sheer variety of effects that come with them. “The free plug-ins that are included with a DAW have gotten substantially better in the last 10 to 15 years,” says Rodd. And if you’re not satisfied with the plugins that come with a specific DAW, you can always download others.
If you want the flavor of a specific analog mixer in a digital package, there is another option: Emulation plugins allow you to create an analog sound in a digital space. While they can’t perfectly replicate analog audio, “digital emulations of older hardware have definitely gotten better over the years,” says Rodd.
Field mixers are worth considering if you’re working on location in film, television, or video production. They plug directly into a camera or audio recorder, allowing you to monitor and adjust mic gain and level.
A good audio mixer has a combination of price, audio quality, and effects that suits your needs.
- Price: While many audio mixers carry a hefty price tag, audio mixers are more accessible today than ever before thanks to advances in sound technology. “It’s no longer about the cost of entry to the tools,” Rodd says. Higher-end mixers come with better circuitry that improves sound quality and effect functionality, but if you’re podcasting, doing voiceover work, or making videos for social media, a less expensive mixer and DAW will suffice.
- Audio quality: The best sound mixers enhance audio quality in a way that refines it for your specific sound requirements. If you plan on recording your own audio and want to use a DAW, look for software with integrated recording. Most modern DAW mixers have recording options built in as well as virtual instruments and effects. Look for at least 24-bit recording as a good benchmark of audio resolution.
- Effects: While most mixers come equipped with signal processing effects onboard, they don’t all have the same features or quality. If a mixer doesn’t come with the effects you’re looking for, such as reverb and delay, you’ll need to add outboard gear to the signal chain—especially for analog mixers.
Some of the most popular mixers, workstations, and interfaces include:
- Allen & Heath ZED60-10FX
- Mackie ProFX10v3
- Yamaha MG10XUF
- SSL BiG SiX
- Behringer Xenyx X1204USB
- Zoom LiveTrak L-20
- Behringer X AIR XR18
- Wharfedale Pro M16 Digital Mixer
- PreSonus StudioLive
- Yamaha TF1 Digital Mixer
- Avid Pro Tools 12
- Ableton Live
- Apple Logic Pro
- PreSonus Studio One
- Sound Devices 552 5-Input Production Mixer/Recorder
- Sound Devices 302 Portable 3-Channel Field Mixer
- Shure FP33 3-Channel Stereo Mixer
- Azden FMX-42 4-Channel Microphone Field Mixer
- Beachtek DXA-SLR PRO HDSLR Audio Adapter
- Audient EVO 16
- Universal Audio UAD Apollo Twin MkII
- Focusrite Scarlett 4i4 3rd Gen
- SSL 2+ Audio Interface
- Audient iD4 MkII
Ultimately, choosing an audio mixer comes down to what you want to do with it. Ask yourself the following questions:
- Will I be recording my own sound? If so, what microphones will I use? Consider the preamps that come with a mixer. You can also acquire your own preamps to use for your audio as needed—but you’d better get a mixer with phantom power if you’re using a condenser mic.
- How many channels and I/O will I need? It’s always better to err on the side of getting a mixer that has more than you think you’ll need.
- Do I want to use something simple and immediately responsive with high sound fidelity? Try an analog mixer.
- Am I working with a podcast, radio, or voiceover work and want to record higher-quality sound? An audio interface is a good choice.
- Am I shooting a film or TV show on location? Add a field mixer to your arsenal.
- Am I looking for flexibility in signal transferal and processing, remote control, and onboard effect options? You may be in the market for a digital mixer.
- Am I okay with keeping the hardware to a minimum and learning the ins and outs of a program? Try using a DAW.
- What other pieces of equipment will I be working with? What kinds of cables do I use? Match with what you already have.
- What do my peers use? Try reaching out to others in the audio mixing community. Chances are that someone experienced in the field will have some good recommendations. No matter your choice, “you can do professional, high-quality work if you have the skill, passion, attention, and perseverance,” says film sound designer and mixer Johnnie Burn.