Audio Converters and audio mixers

You need an audio converter whenever you have to bridge two pieces of audio equipment that use different formats. The most common cases are: connecting a digital source (HDMI, SPDIF, TOSLINK) to an older analog amplifier (digital-to-analog converter, DAC); connecting an analog source to a digital recorder or streaming device (analog-to-digital, ADC); bridging SPDIF coax to TOSLINK optical or vice versa; converting balanced pro signals (XLR, TRS) to unbalanced consumer signals (RCA) or vice versa; and de-embedding audio from an HDMI stream so it can be processed separately from the video.

Analog mixers process audio in the analog domain throughout: signals enter on input channels, pass through analog faders and EQ, and exit on outputs without ever being digitized. They are simple to operate, have no boot time, and never crash. Digital mixers convert each input to digital, do all processing in the digital domain, then convert back to analog at the outputs (or stay digital throughout if outputs are AES/EBU or networked). Digital mixers offer scene recall, complete reset of all parameters, software control, network connectivity, and far more processing per channel; the trade-off is complexity, boot time, and a steeper learning curve.

Count every audio source that will be active at once, then add a margin for future expansion. A small boardroom or podcast setup might need 4 to 8 channels (presenter mic, guest mic, computer audio, music). A worship service might need 16 to 32 channels (pastor lavalier, choir mics, band instruments, playback). A live concert mixer often needs 32 to 64 channels (vocals, guitars, keys, drums, backing tracks, etc). For broadcast and large live sound, 64 to 96 or more channels are common. Always provide some headroom: running a mixer at full capacity leaves no room for an unexpected extra source.

HDMI audio de-embedding extracts the audio portion of an HDMI signal and outputs it on a separate connector (analog stereo on RCA, digital SPDIF coax, TOSLINK optical, or balanced on XLR/TRS), while the video passes through to a display. You need de-embedding when the HDMI source's audio must go to a separate amplifier or audio system that does not accept HDMI directly: a typical example is a sports bar where many TVs share displays but the audio for the active TV needs to feed the venue's PA system through an audio mixer.

Dante, AES67, and AVB are networked audio protocols that carry many channels of professional-quality digital audio over standard Ethernet cable. Instead of running individual XLR or SPDIF cables between every audio device, you connect everything to a standard managed network switch, then route channels in software. Use a networked audio system when you have a complex installation (many sources, multiple zones, large building), when you want flexibility to re-route audio without re-cabling, or when you need to integrate audio with IT-managed network infrastructure. Dante is the most common in commercial AV, AES67 is an open standard, AVB is used in some pro audio and automotive applications.

Conference rooms and corporate AV (combining microphone, laptop, and video conferencing audio into one mix), broadcast and recording studios (the mixer is the central hub), houses of worship (combining many microphone, instrument, and playback sources), live sound venues (front-of-house mixing for the audience, monitor mixing for performers), education (combining classroom microphones with computer audio for recording or amplification), film and television sets (multiple boom and lavalier microphones combined for recording), and podcast or streaming studios (combining microphones, music, and remote guest audio).