---
title: "\"To Source\" vs. \"From Source\""
slug: "to-source-vs-from-source"
updated: 2024-12-17T09:24:30Z
published: 2024-12-17T09:24:30Z
canonical: "docs.telosalliance.com/to-source-vs-from-source"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://docs.telosalliance.com/llms.txt
> Use this file to discover all available pages before exploring further.

# "To Source" vs. "From Source"

## Scope

The intent of this article is to explain what **To Source** and **From Source** means in the Destinations page of the xNode and in some other locations throughout Livewire devices.

## Description

A single Livewire Channel has send and return elements built into it. This is why you see **To Source** and **From Source** as options for stream mode/type in the VX's POH input, the VX's main input (Advanced Receive) section, the xNodes output (destination) section, etc.

These modes are used to specify which part of the Livewire stream is to be used at that interface

## **From Source:**

This is the mode that will be used most of the time. It literally means it's going to use audio from the source, like an xNode source or a VX output channel.

## **To Source:**

- This is audio sent back to the source from an Axia console, also known as a backfeed.
- With codecs and phone channels, the console engine automatically creates the backfeed for returning audio to the caller. In this case, the **To Source** or backfeed is always a mix-minus. This needs to be a mix-minus so that the caller doesn't hear echoes when they speak.
- We can relate this to an analog recording setup too. The **From Source** would be the playback/monitor signal from the tape machine (the source) to the console. Inversely, the **To Source** stream is the tape-send from the console back to the tape machine (the source.) This also needs to be a mix-minus, so that there isn't a feedback loop when the tape machine is in "Input Monitor" mode and is being monitored at the console.
- For Guest Microphone sources, the **To Source** is not a mix-minus because it is meant to go to the Guest's headphones.
- **To Source** streams will also contain any talkback audio sent from the console operator back to the source.

## Conclusion

Both of these audio streams can be represented by a single Livewire Channel number.

Just remember: **From Source** is the regular audio source, like from a node. **To Source** is the return from the console back to the source, the mix-minus or backfeed signal.

GPIO works in this same manner. There is **Source GPIO** and there is **Console GPIO.** More on that is explained [in this example](/v1/docs/controlling-a-vmix-with-console-gpio).