This applies to all Focusrite interfaces and preamps.
TS, TRS, and TRRS are three of the most common audio connectors. They are often referred to as jacks, and come in several sizes, including 6.35mm (¼″) and 3.5mm (⅛″).
The letters T, R, and S indicate the number and arrangement of conductors (wires and connections) that the cable and connector have.
TS — Tip and Sleeve
TS has two conductors — sometimes referred to as 2-pole — one for audio and one for ground. These are arranged on the Tip and Sleeve of the connector, separated by a single insulating band.
TS cables are most commonly used for unbalanced mono signals, such as guitars, with the 6.35mm (¼″) size connector. In the rare case that you need to connect a 3.5mm (⅛″) TS cable to a 6.35mm (¼″) input, you will need a 3.5mm (⅛″) to 6.35mm (¼″) TS adapter.
What to avoid with TS
You can generally use unbalanced mono TS to connect to balanced mono TRS inputs and outputs, but check with the manufacturer of any equipment you are using. The signal will become unbalanced, resulting in a 6dB drop in the signal level and greater potential for unwanted electrical noise relative to a balanced signal.
TS cables cannot carry stereo signals, so you should avoid connecting them to stereo TRS inputs and outputs, as it will result in the loss of one of the two channels.
If you'd like to know more about balanced and unbalanced connections, take a look at this article: Differences between balanced and unbalanced audio.
TRS — Tip, Ring, and Sleeve
TRS has three conductors — referred to as 3-pole — two for audio and one for ground. These are arranged on the Tip, Ring, and Sleeve of the connector, separated by two insulating bands.
TRS cables can be used for either balanced mono, such as the line inputs and outputs on many Focusrite products, or for unbalanced stereo, like the headphone outputs on Focusrite interfaces.
Headphones often use a 3.5mm TRS (⅛″) as standard, so you will need a 3.5mm (⅛″) to 6.35mm (¼″) TRS adapter to connect these to 6.35mm (¼″) headphone outputs, like those found on our products.
What to avoid with TRS
You should avoid using TRS for most guitars, as it can cause issues with guitar effects pedals and similar equipment that is expecting a TS connection.
Although both unbalanced stereo TRS — such as headphones — and balanced mono TRS use the same connector, they are not designed to be connected directly. If you do connect them, one of the stereo channels will be lost, and you may experience additional audio quality issues.
TRRS — Tip, Ring, Ring, and Sleeve
TRRS has four conductors (4-pole), three for audio and one for ground, with a second Ring and a third insulating band. It is generally only seen in the 3.5mm (⅛″) size, most commonly on gaming headsets and headphones designed for voice calling, because the third audio channel can be used for a built-in mic.
3.5mm (⅛″) TRRS
Headsets and headphones with TRRS connectors cannot be connected directly to the headphone outputs on Focusrite interfaces, even with a 3.5mm (⅛″) to 6.35mm (¼″) adapter. Please see the following article for more information: Why does audio from my headset sound unusual?
Mobile phones and tablets will typically use TRRS for input and output, sometimes with an adapter where a TRRS port is not present on the device itself. The mobile phone and tablet port on Vocaster utilises TRRS for video calling and recording audio from the phone or tablet. It simultaneously outputs mono audio and inputs stereo audio. If you'd like to know more, see the Vocaster User Guides: Vocaster | Downloads.