What Is an Audio Patch?

One source can have several references

The input list calls a presenter microphone P1. Its cable enters socket 3 on a stage box. The mixing console uses input channel 1 for that presenter.

Those references can all be correct. They identify different things.

Source identity, physical connection and channel assignment are related, not interchangeable.

An audio patch describes the connections and assignments that make the arrangement work. People may use the word for the actual connection, a group of assignments or the working plan that records them. Clarify which meaning is intended rather than assuming “the patch” is one particular document or screen.

In live sound, the useful question is not simply “Which number is it?” It is “Which source, at which connection, assigned to which channel, for which required destination?”

Physical connections and internal assignments

A physical connection joins compatible equipment through an appropriate interface. For example, a microphone cable may connect to an identified input socket on a stage box. That box is an input/output unit placed where connections are needed; its exact role and connection to the rest of the system depend on the equipment.

In a digital mixing system, a socket or other available input source can be assigned internally to an input processing channel. That channel is where the operator controls and mixes the assigned signal. It is not the socket itself.

For a specific manufacturer example, Allen & Heath's SQ documentation distinguishes input sockets from input processing channels and describes patching between them. It also describes output patching. Those are capabilities of the documented system, not a promise that every mixer offers identical assignments or controls.

An internal assignment does not move a cable. Moving a cable does not automatically update the internal assignment or its documentation. Both need to describe the intended current arrangement.

A networked or digitally connected system may introduce other input references between the physical connection and the console. The responsible audio team must record the mappings it actually uses. This introduction does not teach network setup, device discovery or clock configuration.

An input list is not the whole patch

The input list identifies the sources the performance or programme needs. A patch record relates those identities to the system that will receive them.

The list might say P1, Presenter microphone. The patch might add Stage box A, input 3, assigned to console input channel 1. A separate output record may identify how an agreed mix reaches the audience system or recorder.

One document can contain several of these columns. Their functions still differ. An input list does not prove the stated connections have been installed, and a patch record does not prove they have been checked.

If you are defining the sources rather than their implementation, begin with How to Build an Input List. Do not replace source identities with convenient socket numbers merely to make a sheet look tidy.

Patching is part of routing, not its opposite

Patching and routing overlap in ordinary production language. A console's input or output patch is itself a signal assignment. The distinction here is between identifying connections and assignments, and understanding the complete path to each required destination.

Once a source reaches the intended input channel, the system still needs the relevant mix and output arrangements. A correct presenter input does not establish that the presenter reaches a monitor, a recording or a remote participant.

Yamaha's RIVAGE PM input-patching documentation provides a bounded example: one input port can be assigned to multiple input channels on that system. This illustrates why a socket and a processing channel are different references. It does not establish that two channels are required, that all systems support the same mappings, or that duplication is appropriate for a particular show.

The Signal Flow explainer follows the wider path. This Article concentrates on keeping the identities and assignments understandable within it.

What makes a patch record useful?

Record enough information for the people preparing and checking the actual system to identify the same signal. Depending on the production, that may include:

- source reference and clear name; - capture or connection arrangement where agreed; - stage-box, local-input or other device identity and port; - assigned console input channel; - relevant output or destination references, or a link to the current routing record; - who owns preparation and checking, current revision and outstanding questions.

Specify the device as well as the number. “Input 3” is incomplete where several boxes or systems have an input 3.

There is no mandatory universal column set. A small analogue arrangement and a networked festival system need different detail. A split to another console or recorder can require its own mapping and responsibilities; one team's channel order is not automatically every team's channel order.

Labels and channel names help people work. They are not independent proof that the source behind them is correct.

Worked example: P1 is not socket 1

A fictional conference has a presenter microphone, an audience-question microphone and left/right programme playback. Its audio team has agreed suitable capture and connection arrangements before this extract begins. There are no remote contributors in this example.

The room audience and an agreed programme recording both need the two microphone sources and playback. This is a partial mapping extract, not a complete system specification, recording design or connection instruction. The numbers are illustrative choices, not a recommended order.

The destination column states the requirement. It does not specify buses, output sockets, processing or how a recording is made. The audio team must establish those arrangements separately.

First discrepancy: the names look right, the sources do not

During the planned, coordinated source-identification check, the audio team finds that the presenter source reaches the channel labelled Audience Q&A. The question microphone reaches the channel labelled Presenter.

This observation does not establish a failed microphone or cable. The team compares the current source identification, physical entry points and internal assignments with the approved mapping.

For this example, that investigation confirms the two physical entry points match the table, but the internal assignments are reversed: stage-box input 3 is assigned to channel 2, and input 4 to channel 1. The responsible audio lead agrees the correction to the intended channel assignments. The team does not swap cables or rename sources merely to conceal the discrepancy.

This is an explained finding, not an instruction to make the same adjustment on another system. The audio team coordinates the change with the people operating the affected system and required outputs, using the applicable equipment instructions and agreed working method. Nothing here authorises repatching a live programme without that coordination.

The team then checks P1 and Q1 against their intended channels and verifies the playback identities within the agreed check scope. The record identifies which mapping was corrected and what was checked afterwards.

Second discrepancy: correct input, missing destination

After the input correction, Q1 reaches the intended channel and can be heard in the room. A representative recording test is played back and the question microphone is absent.

The input identity check has not failed again simply because another destination is wrong. Nor has the complete requirement passed because the PA works. The observation tells the audio and recording leads to examine the affected downstream routing and recording path. It does not identify the cause by itself.

The missing recorded question remains open while those leads investigate and agree the correction. They repeat the affected receiving checks and play back a new representative recording before reporting that destination as checked. The coordinator records the result and any remaining limits rather than declaring every output accepted on behalf of the specialists.

The lesson is the separation of evidence: the physical entry point, the console input identity and the received recording each require the relevant confirmation. A correct number or one successful destination cannot stand in for all three.

ILLUSTRATIVE SCENARIO

A changed patch changes the checked state

A line check uses the current source and patch information to establish the agreed input identities and relevant paths. Its scope must be stated. It is not automatically a complete recording, monitoring or programme test.

If a connection or assignment changes, identify the affected sources, channels and destinations. Update the current record and repeat the relevant checks. Do not copy an earlier pass onto a path that has changed.

The audio team must review equipment compatibility and any affected operating conditions. This Article does not prescribe phantom-power settings, gain changes, cable-disconnection procedures or a universal mute sequence. Console files, scenes and recalled settings need review for their actual system effects; an old file is not proof of a current patch.

For recording or streaming, the destination requirements guide explains what each output should contain and how receiving checks are agreed. That brief and the technical patch answer connected but different questions.

Keep a shared identity through the handover

The person preparing the patch and the person operating the console may be different people. The relevant stage, audio, monitor and recording contacts need the portions of the current mapping that affect their work. Staffing and titles vary; agree responsibility rather than assuming every event has a separate patch engineer.

A handover should say what is intended, what is physically connected, what is assigned, what has actually been checked and what remains open. A blank socket field is not permission to choose an arbitrary connection. A drawing or channel label does not replace source confirmation.

Keep the source identity clear even when the system mapping changes.