Phase Reverse? Polarity reverse?

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Your rant is all great and wonderful....

but actually, massenburg calls it a Phase button...not a phase invert/reverse

Avalon calls their button Polarity (correctly)...and uses the term "phase shift" correctly later on in the specs.

And, you can't really dispute the scientific definition of phase....no matter which "legendary" engineer/manufacturer said it.

Phase: the time position (or angle in the complex plane) within a cycle of a periodic waveform
So a shift in time is equivalent to a change in the initial phase. Conversely, a change in the initial phase is tantamount to a shift in time.
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To reverse phase would be the same as reversing time.
 
ford van is one of those guys that comes to a party wearing some ridiculous shirt and acts like he just blew everyone's minds and changed their lives.
 
Diffusion said:
oh. so basically I just shouldnt fuck with it when im recording?
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Absolutely not. You should be fucking with them all the time. Or at least, at some point.


Any time you have two signals, you can have phase discrepancies. Now, these may or may not be a problem, but flipping the polarity will change the way the different frequencies interact. Sometimes they will cancel one another out. Sometimes, they will reinforce one another. Flipping the phase will change those relationships, and usually one will sound better than the other.

This is MOST noticeable with similar or identical signals, such as multiple mics on the same source (such as multiple mics on a guitar cabinet), or to a lesser extent on a pair of doubled guitars. But it can have an effect even on unrelated parts, so it is worth it to flip things around as an experiment while mixing. Sometimes it helps, sometimes it doesn't, but you may as well check it out. Certainly, you can't hurt anything by flipping things around. If it's not better, just flip it back.

There is another reason to use them. Some times you will use multiple mics on a source, on opposite sides (top and bottom snare mics, or front and back guitar amp mics, for instance). The opposite sides of the source put off opposite pressures (one side starts off with positive pressure, the other with negative pressure). This leads to the two signals having opposite polarity, so you flip one, and the two signals will reinforce properly.


Light

"Cowards can never be moral."
M.K. Gandhi
 
think of what a PHASER does....you know, the audio effect you hear on a lot of guitar tracks.

The electronic phasing effect is created by splitting an audio signal into two, electronically shifting the phase of one signal (usually by passing it through an allpass filter), and then recombining the two signals. The allpass filter passes all frequencies unchanged in amplitude, but has a frequency-dependent, non-linear effect on the phase of each frequency. The result is a signal whose overall spectrum is shifted by various amounts at each frequency. For example, the phase of a frequency at the low end of the spectrum may be shifted by 1/4 of a wavelength, while a frequency at the high end of the spectrum may be shifted by 3/4 of a wavelength.
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note the term phase shifted. which has to do with time.
 
bennychico11 said:
Your rant is all great and wonderful....

but actually, massenburg calls it a Phase button...not a phase invert/reverse

Avalon calls their button Polarity (correctly)...and uses the term "phase shift" correctly later on in the specs.

And, you can't really dispute the scientific definition of phase....no matter which "legendary" engineer/manufacturer said it.

Phase: the time position (or angle in the complex plane) within a cycle of a periodic waveform


To reverse phase would be the same as reversing time.
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From Massenburg's manual:

Phase switch, illuminated pushbutton: in-phase (LED off), phase reverse (LED on)

From the Avalon specs:

Input polarity phase reverse

Every fucking engineer for the last 4 decades has called it "phase reverse", and every one of us has understood what that means.
 
Ford Van said:
Every fucking engineer for the last 4 decades has called it "phase reverse", and every one of us has understood what that means.
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But but but the original poster didn't understand what it meant, which is the point of this thread. People basically told him they mean the exact same thing, but one is a common misnomer.
 
bennychico11 said:
Phase: the time position (or angle in the complex plane) within a cycle of a periodic waveform


To reverse phase would be the same as reversing time.
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The definition is the POSITION in Time (time position). If you reverse it (ie flip it 180) then it would be the reverse of what it was (reverse phase/ inverted phase). It is being used correctly.
 
Of course it is being used correctly! That button has been referred to as the "phase reverse" button on gear since the freakin' beginning of time! All of a sudden every major player in the audio developement is WRONG because somebody wants to play with words?

:rolleyes:
 
Ford Van said:
Of course it is being used correctly! That button has been referred to as the "phase reverse" button on gear since the freakin' beginning of time! All of a sudden every major player in the audio developement is WRONG because somebody wants to play with words?

:rolleyes:
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No, but people might as well understand what they are talking about. Knowledge isn't a bad thing.
 
NL5 said:
The definition is the POSITION in Time (time position). If you reverse it (ie flip it 180) then it would be the reverse of what it was (reverse phase/ inverted phase). It is being used correctly.
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you're not flipping the phase of it though...you're flipping the polarity, the +/-
Remember, polarity=polar regions...you know, north and south.
phase concerns the time relationship between identical signals. The time difference between them is called the phase shift, and it is measured in degrees.
A waveform, like all analog audio signals, is an alternating-current (AC) signal, which means that the signal voltage repeatedly alternates from positive to negative. The voltage starts at 0V, goes positive, then negative, then back to 0. This completes 360 degrees of the waveform, or one cycle.
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360 degrees=one cycle in time....if you put this on a xy coordinate graph (reverting back to calculus for one second) this corresponds to a horizontal movement of the waveform along the graph. Adjusting the cycle 180 degrees would be a phase shift. You're moving it along the x axis.

A quote form Electronic Musician:
For example, on many mixing consoles, each input has a switch labeled "Phase," and the user manual might say that the switch "puts the signal 180 degrees out of phase." This switch doesn't really shift the signal in time; it simply inverts the signal's polarity.

Why the "Phase" label? Well, in the early days of electronics, the term phase was used to refer to the polarity of audio signals, and the word polarity was reserved for describing power signals. Technically, this terminology isn't correct for complex signals, but the industry still uses this convention.
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more math: http://mixonline.com/mag/audio_understanding_phase/

Yes, we all know what they mean when someone says "phase reverse" or "polarity invert." The end of the audio world is not soon at hand because everyone switches (no pun intended) these two words around.

Manufacturer links are all great and wonderful...but here's another quote from a "major player in audio development"

The polarity of a loudspeaker refers to whether the driver moves outward or inward with positive-going signal, and can be corrected by a simple wire reversal. Remember that phase means relative time; phase shift is actually a time delay. The so-called phase switches on consoles are actually polarity switches, they have no effect on the time of the signal!
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-Bob Katz
 
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If you want to make an argument out of such a worthless thing to argue over, then you would have to specify more than just calling it a "phase" switch. You would have to say

"it is wrong to call it an electrical time phase switch"

For instance, I am going through a PHASE where I am considering putting a big block in my car, I will likely go to another phase where I think, "gee, a small block will make more sense"

these are both phases and have NOTHING to do with lead time or lag time in sine waves

SO call it a fuckin phase switch, stop being a pussy

If its up, the signal is in its "in phase" if you press it in itsd in its "out phase"

Run the same signal to two channels push one phase switch in and leave one out

hey now you can say "its out of phase!"

see how easy?

Now go argue about something important, like how in this day and age plugin I/O is 24 bits in some DAW's
 
pipelineaudio said:
If you want to make an argument out of such a worthless thing to argue over, then you would have to specify more than just calling it a "phase" switch. You would have to say
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hahah, we're having a discussion, not an arguement. I haven't been sarcastic nor made fun of anyone. They have one point of view on this topic, and I have another. This is the whole reason for forums! To discuss! I don't know how this makes me a pussy....excuse me, "fuckin' pussy"

Now, since you've given me another example to work with...let's work with it.
Since I've already stated phase has to do with a position in time, or a point in time...let's just say phase=a point in time.
For instance, I am going through a POINT IN TIME where I am considering putting a big block in my car, I will likely go through another POINT IN TIME where I think, "gee, a small block will make more sense."

Wow...seems to work for me.

If its up, the signal is in its "in phase" if you press it in itsd in its "out phase"
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With what? How can a mono signal be in phase with itself? How can it be out of phase with itself? Don't we need another signal for it to be considered out of phase....another channel that is making it out of phase?

Put two speakers at equal distance to your ears playing a sine wave. Everything's great, right? Now move one of those speakers further away from you. The polarity is the same on the signal...the polarity is the same on the speakers...but they still become out of phase with eachother, right? If you were playing a sine wave and they were exactly 180 degrees out of phase and you flipped that polarity switch 'causing the compression and rarefaction of the wave form to switch places, then everything would be fine and dandy (although there would still be a delay). But we don't play sine waves...we play complex waves. And pushing the polarity button isn't going to correct it 100%, because if the speakers are spaced apart...there is still a slight delay in our signal. It's just going to make it sound better.

Our audio signal is phasing in and out. Switching the polarity is what happens in the electrical world. We switch the polar opposites, or the +/-

Now, pipeline, if you want to join our little adult conversation...feel free to. But let's grow up and stop spoutin' off derogatory comments.
 
- or +, + or - sheesh who knew one button could be so hard to describe... :D
 
Oh for the sake of ford van's pants!

Of course *a SINGLE* signal traveling down *a SINGLE* path cant be out of phase with itself

Polarity is the correct term, but again I say the word "phase" istself CANNOT be right or wrong to use, it would need to be qualified with some more terms or more context

for instance

NOUN: 1. A distinct stage of development. As in at this stage the wavefoirm is going UP, but if I hit this phase switch, it flips to its OPPOSITE stage of development (going down)

2. A temporary manner, attitude, or pattern of behavior. Right now its reached positive altitude, if I hit the phase switch, it goes to a negative altitude

3. An aspect; a part. Hmm its on its upward PART, when I flip the switch its on its downward PART

Now if the switch were labeled IEEE Phase, then you would have a point
 
Thought I'd check in, see how the polarity thread was going. Almost as good as the DI thread in Recording Techniques, I see.
 
easychair said:
Almost as good as the DI thread in Recording Techniques, I see.
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nah, you guys don't have a "fuckin' pussy" in your thread :rolleyes:
 
bennychico11 said:
nah, you guys don't have a "fuckin' pussy" in your thread :rolleyes:
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that can easily be arranged, but it needs to be warranted
 
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