#1
So I've been playing around with my bass sound for a bit, routing the one take to a track for subbass, one for some overdrive .etc and I only realised today that you have to flip the phase on one track otherwise they just cancel each other out. Is this correct or have I managed to mess something up because I've NEVER heard this mentioned in all the tutorial's regarding bass sound before. Are there any other common issues regarding phase I may not know about?
#2
Flipping the phase will cancel out. There are a few situations when you need to use phase reversal. Are you using 2 mic's or just re-amping one take back out to the amp?
#3
Quote by Drummerrrrr?
So I've been playing around with my bass sound for a bit, routing the one take to a track for subbass, one for some overdrive .etc and I only realised today that you have to flip the phase on one track otherwise they just cancel each other out. Is this correct or have I managed to mess something up because I've NEVER heard this mentioned in all the tutorial's regarding bass sound before. Are there any other common issues regarding phase I may not know about?

Flipping the phase is, apart from being an improper term, not something you really need to worry about unless you are using a separately recorded track/sample and trying to time-allign the two (or more) tracks.

It should actually be called 'inverting the polarity', for starters because phase is a 360 degree rotational matter (phasors in the waveform is how it gets its name) and by flipping the waveform 180 degrees you are only fully-treating signals that are precisely 180 degrees out-of-phase with each other.

As for when it is important: say you record a snare drum with two mics; one on top and one underneath. To get the full effect from them, you want them hitting at exactly the same time, to make use of the two textures without smearing the transient. But when they are perfectly in time, the initial transient heads positive first in one mic and negative in the other. This is because the drum head bounces up and down/vibrates (to create the sound pressure waves we detect as audible sound) and of course has to move one direction first... away from the stick, as the stick hits.

Basic principles of audio physic dictate that two identical waveforms that are opposing in polarity (180 degrees out of phase) will create silence when played at the same volume as the speaker cone you play the sound through cannot move backwards and forwards at the same time. Therefore in our example, two very similar (not identical though, as mic type/placement/signal path etc. will always give a different signal no matter how much you try to get it identical) waveforms are created at close to 180 degrees out of phase. To get the desired sound, we must 'flip the phase' (read: invert the polarity) or all manner of freakish things can occur - in most cases the low end is hollowed out and the midrange completely disappears... can be used to interesting effect on kick drums if you're suffering to get a 'metal' kick sound at a live gig, and have a spare mic you can place at the right distance from the other mic (trial and error will get you to the position it works best, unless you are great at maths and have perfect pitch, in which case you could calculate the wavelength of the kick's low frequency thump, and work out half that length and put the mic's that length apart...).


Hope that isn't too boring a reply and clears things up a bit!
Hey, look. Sigs are back.
#4
Quote by Drummerrrrr?
So I've been playing around with my bass sound for a bit, routing the one take to a track for subbass, one for some overdrive .etc and I only realised today that you have to flip the phase on one track otherwise they just cancel each other out. Is this correct or have I managed to mess something up because I've NEVER heard this mentioned in all the tutorial's regarding bass sound before. Are there any other common issues regarding phase I may not know about?


you have 2 mics or 1 mic?

If you are using 1 mic, on 2 tracks with different effects on them, phasing one will cancel the sound out. thats normal.

gonna try to explain...

its very hard to visualize if you have not taken the physics behind it.

think about a mother pushing her child on a swing.

as long as the mother pushes the child right as the child is falling away, the swing will keep on swinging... its "in phase"

however if the mother pushes while the child is going towards the mom, the child will slam on her hands, and all that energy will be lost, absorbed on impact. in other words, the mothers pushing was "out of phase" with the swing.

basically what I am trying to say is that sound waves have to be in unison with each other, or else some frequencies will cancel one another.
#5
Yep, I understand that which is why this doesn't quite make sense. I have a bass DI track which I run into Pod Farm for midrange. I also route the same signal to another track, compress the shit out of it and lowpass everything but the very low end. Each track sounds fine on it's own though, when I play the two at the same time I loose all my low end or at least where the subbass track sits. This is what confuses me as these should be in phase, yes?

Great explanations though, guys, definitely cleared a lot of stuff up for me!
#6
maybe theres some kind of a delay or something? which is putting one out of phase with other other?