# Delay Downmix Matrix

### What the Downmix Matrix Does

The Downmix Matrix routes signals from **main beams** to **fill and LF beams**.

It allows you to:

* send the same signal used by your main beams to fill or LF beams
* apply **gain and delay per routing point (crosspoint)**

This routing is **required** if your project contains Fill or LF Function Groups. Without Downmix routing, fill and LF beams will not receive signal from the mains.

The Downmix Matrix is organised as follows:

* **Rows** represent **Main Function Groups** (signal sources)
* **Columns** represent **Fill and LF Function Groups** (signal destinations)

Each intersection between a row and a column is a **crosspoint**.

Routing is always created from **mains to fills or LF** by enabling a crosspoint at the intersection between them.

{% hint style="info" %}
The Downmix Matrix is must be used in conjunction with **Function Groups**.
{% endhint %}

Before using the Downmix Matrix:

* Main beams must be assigned to a **Main Function Group** (all beams are auto-added to Main Function Groups unless explicitly marked as fills).
* Fill beams must be assigned to **Fill Function Groups**
* Low‑frequency beams must be assigned to **LF Function Groups**

If no Fill or LF Function Groups exist, all beams remain in the Main Function Group and the Downmix Matrix will only show mains.

***

### Creating Downmix Routing

When Fill or LF Function Groups exist, the Downmix Matrix is initially **empty**.

No routing is created automatically. You must explicitly define routing by enabling crosspoints.

To create routing:

1. Open the **Downmix Matrix**
2. Locate the desired **Main Function Group** row
3. Locate the target **Fill or LF Function Group** column
4. Enable the crosspoint at their intersection

Using Function Groups allows you to create routing relationships quickly without working beam by beam.

***

### Gain and Delay at Crosspoints

Each crosspoint in the Downmix Matrix supports:

* **Gain**
* **Delay**

These values are used to control the system‑level relationship between mains and fills or LF beams.

{% hint style="info" %}

## Editing gains and delays

In **Plan**, you can edit:

* Downmix routing (crosspoints)
* Crosspoint gain and delay
* System beam gains and delays

These system‑level values are exported and brought into Control.

In **Control**, you can edit:

* **User‑level beam gains and delays**

System values defined in Plan and user values edited in Control are separate and serve different purposes.
{% endhint %}

***

### Push and Pull Gain and Delay

The Downmix Matrix includes a **push / pull** mechanism that allows you to control where gain and delay are applied in the signal chain.

For each beam, open the **three‑dot menu** to access the following options:

* Push gains/delays to the matrix
* Pull gains/delays from the matrix

When using push or pull:

* Pulling gain or delay from the matrix to the beam level only has a meaningful effect when multiple crosspoints contain values.
* This effectively **normalises the relationship**, allowing common gain or delay offsets to live at the beam/matrix level while preserving relative differences between values.

This allows you to shift gain and delay between beam‑level and matrix‑level.

***

### Export and Persistence

Downmix routing is exported with the **.holoplot** file.

Downmix Matrix configuration persists when moving projects between **Plan and Control**, ensuring routing and system‑level tuning remain intact across environments.


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