Clipping master fader

[sidereal-studios]

This may be a dumb question, but...

I've got two mono tracks I'm mastering. With both faders set to unity, I play them without a master fader and there's no clipping indication. I then create a master fader, also set to unity and it hits red. Everything's dry right now, no plug-ins.

If everything's set to unity, and there's no clipping from the two tracks themselves, why would a master fader (also set to unity) suddenly clip the output?

[germ]

First up, you said 2 mono tracks. are these left & right components of a stereo track or are they both single mono?

If the 2 tracks are split stereo & the levels are close to zero and you havent panned them left & right you will have an overload on your Master Fader ( from memory a 6Db lift)

If that isnt the cause , perhaps you could provide more information

[sidereal-studios]

They're two separate tracks (one piano, one vocal), both mono, no panning on either track.

It seems strange that if everything on the mixer is at unity, why would the master fader clip when the two audio tracks aren't. Shouldn't the master fader just take what's already there and not be boosting anything? When there are no plug-ins instantiated, it's just like a volume control right? At unity, I don't see any reason for it to clip.

[Guy Staley]

Anytime you sum signals together, the result is more amplitude; provided there's no phase cancellation happening.

My guess is that your two mono tracks are very close to 0dBfs which, although fine by themselves, when summed together are are overloading the summing bus.

That's why they call it summing; as in mathematics when you add one integer to another, you get a SUM integer which is more than either integer by itself.