> For the complete documentation index, see [llms.txt](https://qudelix.gitbook.io/home/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://qudelix.gitbook.io/home/general/active-ground.md).

# Active Ground

The Qudelix DAC/AMP product supports Qudelix's unique Active Ground output mode.

Active Ground Mode is a feature that converts BALANCED output to suit UNBALANCED input. It actively controls the ground terminal using an operational amplifier (OPAMP) to improve sound quality.

{% hint style="info" %}
Active Ground actively maintains the GND reference through the output of the OPAMP.
{% endhint %}

<figure><img src="/files/CYhjqmtIiESZw7GJHjyK" alt="" width="563"><figcaption><p><strong>Active Ground Control by OPAMP</strong></p></figcaption></figure>

| BALANCED output (2.5/4.4mm) | UNBALANCED input (3.5mm, RCA, AUX) |
| :-------------------------: | :--------------------------------: |
|              L+             |                  L                 |
|              L-             |             Common GND             |
|              R+             |                  R                 |
|              R-             |             Common GND             |

For the Active Ground Mode, the BALANCED output must be connected to the UNBALANCED input as shown above, and an adapter cable or gender adapter is required.

{% hint style="info" %}
**2.5/4.4 Male to 3.5 Female Adapter**

[**https://shorturl.at/cuvxD**](<https://shorturl.at/cuvxD&#xA;>)

[https://shorturl.at/rKMX6](<https://shorturl.at/rKMX6&#xA;>)

[https://shorturl.at/noABG](<https://shorturl.at/noABG&#xA;>)

<https://shorturl.at/gpU02>
{% endhint %}

Some earphones and headphones cannot be replaced with a full-balanced cable. In such cases, the Active Ground Mode can significantly improve sound quality. Additionally, using the Qudelix device as a preamp and connecting it to another amplifier's RCA or AUX IN can completely eliminate noise caused by ground loops.

<figure><img src="/files/SFSRddDeTpTDrNHP2Zir" alt=""><figcaption><p>Active GND</p></figcaption></figure>