Reply To: Scarlett 8i8 3rd Gen

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As far as I know the 4i4 is the “biggest” Focusrite Scarlett interface that can work with USB power only (my 2i4 works that way).
Any larger interface needs more power than USB can deliver, so a power supply is needed (for the 8i6 as well as the 18i8, the 8i8 in the title does not exist, but thiat might be a typing error).