Curious Interface Question

[Johnbee58]

Just wondering-My Focusrite interface is a Scarlett 6i6.  It has an AC adapter and requires being plugged into an AC outlet.  Focusrite interfaces below the 6i6 (the 2i2, for instance) get their power strictly from the computer and do not require AC.  Why is this? 

When I bought my Scarlett three years ago, I was hoping that since it needed to be plugged into the AC it would use less processor power, but that's not the case.  Actually it requires more of the computer's CPU power than my old Line 6 Toneport.

 

?John B.

[Wibbles]

1 hour ago, Johnbee58 said:

Just wondering-My Focusrite interface is a Scarlett 6i6.  It has an AC adapter and requires being plugged into an AC outlet.  Focusrite interfaces below the 6i6 (the 2i2, for instance) get their power strictly from the computer and do not require AC.  Why is this?

I'm guessing it might be down to the number of inputs/pre-amps.

https://www.soundonsound.com/reviews/focusrite-scarlett-6i6-scarlett-studio

[bats brew]

only so much juice you can pull to power phantom powered preamps

[Leadfoot]

You're better off with an a.c. powered unit.

[InstrEd]

2 hours ago, batsbrew said:

only so much juice you can pull to power phantom powered preamps

Bingo

31 minutes ago, Leadfoot said:

You're better off with an a.c. powered unit.

Most of the time yes.

[antler]

Sort of related to this, I too have a question about AC powered interfaces. My first gen 8i6 is AC powered and doesn't have its own power switch; the mains switch acts as the power switch. If I leave my interface connected to my PC by USB, is there any chance that when I power my 8i6 on, there may be a power surge from the mains outlet that could damage my PC? i.e. should I always power on my 8i6 before connecting it to my PC via USB?