Bypassing M-Audio mic preamps

[Jevil]

I've been using a M-Audio Profire 610 for the last 2 years at home. Nice gear for the price and the octane preamps are great.

I want to take some mic tube preamp from studio and connect it to the profire. Is there anyway to bypass profire's preamps? What about connecting it to rear Line Inputs?

 

[Trevoire520]

On the 2626 using the line inputs bypasses the preamps, so I'd assume it's the same on the 610.

Easy enough to test, just plug something into the line input and twist the gain knob to see if it changes the level. If it doesn't make a difference then the preamp is bypassed.