Applies to: Scarlett 16i16, 18i16 4th Gen

Both the Scarlett 16i16 and 18i16 4th Gen units can be bus-powered. These units require 5V / 3A – due to this, you will need to make sure that, on your PC or Mac, the USB port in use meets this specification and that you use a 15W USB-C to USB-C cable.

15W USB-C port 

• Mac – all Macs that have Type C ports should output 15W, except for the one found on the 12” MacBook (this only outputs 7.5W)
• PC – whilst the majority of type C ports will output 15W, the best way to tell is to check with your PC’s manufacturer / USB port manufacturer

Under the USB Power Delivery Specification, the following USB-C ports should provide enough power:

• USB 3.1
• USB 3.2
• USB 4.0

I am using a compatible port and the 15W USB-C cable, but the interface still won't bus power

Windows

If you are on a Windows PC, we recommend optimising your USB ports and your computer for audio using our optimisation article, which includes steps for optimising USB power: Optimising Windows for Audio

If there are still issues, it is often common that USB ports share power with other USB ports on the system, and the maximum power delivery might already be being used. We recommend unplugging other USB-powered devices and reconnecting the Scarlett.

MacBook Pro & MacBook Air

From our testing, we have seen that MacBook power delivery can not always send the required power to all ports when multiple USB-powered devices are connected to the same MacBook.

If your MacBook is not bus-powering the 18i16 or 16i16, we recommend unplugging any other USB devices which are also using USB power and try reconnecting your Scarlett.