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
A few years back, I introduced the concept of proper relative polarity to a well-known recording engineer in NYC. He said it was never a practise in any recording studio...I was shocked and bummed. When I asked the foley artists in Hollywood the same, all I got were blank stares.

I learned how to listen for it from an old Madrigal/Mark Levinson national sales rep when I worked retail north of Detroit in the 80s, and have a copy of the Wood Effect...a small paperback explanation of why this is an serious issue for ALL audiophiles.

My recording engineer friend called me a few months after his 'schooling', when he turned in his first phase-insured multi-track capture for mastering to Bob Ludwig. Ludwig apparently makes a habit of listening to each of the tracks turned into his studio before the capture engineer leaves, and this time he asked if my friend had paid attention to absolute phase. For the first time, all of them were in phase...and he wanted to know if it was co-incidence or more!

When I heard from my now friend-for-life, he was three feet off the ground, ecstatic that his mentor had noticed that he had learned and applied something new!

I took this as a bigger good sign...at least Bob Ludwig can hear absolute phase, and makes a practise of correcting it with the multi-tracks submitted to him for mastering! Of course, it begs the question why Ludwig hadn't bothered to school my friend himself...

Three cheers for the golden ears! (although one less for selfish pride hindering the growth of many for personal profit, how much of Ludwig's reputation is from this single applied gift?! Although, if he is anything like me, he might not have been able to identify what was flowing from him as naturally as a blink or exhale!)

Even more kudos for the rest of YOU who notice these things...and keep an entire industry of maniacs kicking.

Truly,
John
BTW, anyone who says this isn't an issue doesn't realize that the compression of air molecules happens before the rarefaction of any waveform that we can hear...except perhaps the duck's quack.

I've always wondered why those don't echo...
Gannon...How do you know that? Did you make some measurements? I have observed (while traveling in the Suez canal) that the bow wave of a ship is a trough before the crest. Likewise a Tsunami is preceded by the ocean going out before the wave comes in. In the case of sound in air...consider a drum. Surely the polarity of the sound wave will differ depending on which side of the drum you hear it from.

The behavior of a sound wave propogating in air is a whole lot more complex than you think. And anyway, as others have noted the polarity of signal on recordings is so mixed up that, IMHO, it is a waste of time to worry about it.
As one might guess, I agree completely with Eldartford and others who expressed similar sentiments. But it goes back to what I stated above: if you DO care a lot and if you CAN hear the "difference" consistently, get yourself a preamp with a phase switch, preferably on a remote control.
The Herron Audio VTSP-2 preamp has absolute phase on its remote. Attention to absolute phase via a remote is just one of the little things that add up to a great sounding system. It goes along with dressing cables, cleaning contacts regularly, running degaussing sweeps, etc. If we were normal, we wouldn't be audiophiles ;-)