Reversing absolute phase


Hi there,
I heard this phrase before and was wondering, what does it mean and how do you do it?

Any specifics would be appreciated.

Thanks in advance!
mariasplunge
As a recording engineer myslef I agree with Tbg. You just have to know for sure what the poarity of your equipment is. The only caveat is when you're multi-micing with lots of bleed which is something to avoid anyway for this very reason. It is obviously easier the fewer mics and outbaord equipment you use. There is a standard as I mentioned above. It's just that most engineers don't pay enough attention to ensuring it all the way down the line to the point of it being a crap shoot whether any given recording is phase coherent within a given cut, throughout the allbum, or given phase coherency, which polarity it's in. So the question as I see it is not whether it could be but whether the industry could be effectively improved.
Following all before I'll try to be simple for you. I asume you want to ensure your system will correctly reproduce a recording which is 'in correct phase'. If I were helping you confirm this we would 1st play and carefully listen to a CD recording- that is known to yield correct sound when played through a system with correct setup-, paying attention to detail and clarity, dynamic swing and bass response and soundstage. We would then reverse the leads on back of each speaker and listen again. Hopefully we will clearly hear and agree that one way sounds better- clearer, more detailed, less sibilance, more exciting & fun to listen to- than the other. Obviously the way that sounds better is the way the leads should stay. I would use a recent "Reference Recordings" CD to do this as (Keith Johnson is respected for being fussy about sound) I know his recent recordings are correct. If you use a TT we would do the same, with a Ref Recordings record -but switch the leads at your cartridge -since we have already determined what sounds correct for CD. Again the leads will be left where they sound best. As far as Radio-don't worry about it. It is true that recordings are not all in correct phase, and I have also found that even radio stations are not all correctly set up, so it is not possible to have radio consistently correct-even if you use just one station. Others have commented on the benefit of a pre amp that will allow for switching phase; and it is quite a benefit particularly for fussy listeners of classical music where the recordings are usually much longer than rock,jazz,EZ listening. Please let me know if this is helpful: or not.
tbg- the industry standard is for things to be in phase and in polarity. it doesn't mean every recording is but the recordings most people prefer flipped aren't one way or another but in between and are preferred one way by a listener.
polarity is the correcting wiring. Don't confuse this with phase. Phase takes place between more than one source, like two microphones. if they are both in polrity, say pin 2 hot and correct they may be slightly out of phase with each other. when you start to correct an already mixed record with an absolute flip , you are usually choosing whatever sounds better, not correcting an absolute polarity issue.
Mothra, I don't think there is an industry standard. We have no way to know whether what people prefer in polarity is correct polarity, the best of quite mixed polarities on a given recording, or even incorrect polarity. This is the sad state of affairs given industry indifference concerning polarity.

Unfortunately, most of us lack the easy capability to invert polarity by means that do not degrade the signal.