Question about phase reversal...

[jrhager84]

My Firestudio and Digimax don't have any phase reversal switches (which kind of upsets me). I'd like to test phase on all of my channels, so my question is this:

In Cubase, in the mixer window, there's an option to flip phase on each channel. If I flip phase in monitoring mode, will it record with an inverted phase, or is it just phase delaying it? Thanks in advance,

-Joel

[Broken_Hal0]

It wont put the phase reversal into your mix if it is through monitors , you should have a software effect somewhere in there that will deal with the phase which you can run through a send or directly onto the channel. Im not sure with cubase though , Im unfamiliar with it , but I know in Sonar 6 there is a phase effect.

Neil
Plenty Of Rope / The Little Studio

[amra]

In cubase, every channel strip has a phase reversal button on it. It looks like a zero with a line through it, and if you hover over it, it says something like "input phase"

[jrhager84]

Im so horrible at asking questions lol. I know of the button, and im asking if it does the same thing as if the firestudio had it. Is it the same as flipping the pins, or is it just a simulator? Thanks dudes...

[amra]

No, it is not the same, but the effect will be the same, as far as your mix is concerned....

[noisewreck]

Actually, in a mathematical sense it IS the same. In fact, in both cases, you're not really playing with the phase, but you're reversing polarity. When you switch pins 2 and 3 around, you swith the positive and negative terminals on the analog cable. This results in reporducing the wave that's the exact opposite of what would be recorded with "normal" connections, i.e. if you graph the resulting waveforms of "normal" polarity and reversed polarity outputs, they will look like mirror images.

The same exact thing happens with the "phase" switch in Cubase. All it does is flip the polarity of the waveform, i.e it does NOT delay the signal which is indeed what phase related tools would do.

Furthermore, engaging the polarity reversal switch in Cubase's mixer and performing the phase reverse process in Audio->Process, will yield the same exact result. I mention this, because it may potentially be less CPU heavy to do it this way, instead of at the mixer level.

[IronFlippy]

Originally Posted by noisewreck

Actually, in a mathematical sense it IS the same. In fact, in both cases, you're not really playing with the phase, but you're reversing polarity. When you switch pins 2 and 3 around, you swith the positive and negative terminals on the analog cable. This results in reporducing the wave that's the exact opposite of what would be recorded with "normal" connections, i.e. if you graph the resulting waveforms of "normal" polarity and reversed polarity outputs, they will look like mirror images.

The same exact thing happens with the "phase" switch in Cubase. All it does is flip the polarity of the waveform, i.e it does NOT delay the signal which is indeed what phase related tools would do.

Furthermore, engaging the polarity reversal switch in Cubase's mixer and performing the phase reverse process in Audio->Process, will yield the same exact result. I mention this, because it may potentially be less CPU heavy to do it this way, instead of at the mixer level.

100% correct, listen to this guy. Please get out of the habit of saying "phase" reversal. It's polarity reversal, but manufacturers know that most people say phase, so rather than to confuse the majority of their customers, they purposely mis label it.

On a side note, playing with polarity reversal is fun! Pick a song, play it in mono with the polarity reversed on one of the channels. Anything center panned will get canceled out, leaving only the artificial reverb trails (or any other effects applied to it that were in stereo).

[jrhager84]

Now is that polarity reversal done BEFORE record if it is engaged, or is it something you do AFTER you record. I'd like to do the "gold standard" phase check with all of my mics to get my kit sounding good.

[jrhager84]

Originally Posted by IronFlippy

100% correct, listen to this guy. Please get out of the habit of saying "phase" reversal. It's polarity reversal, but manufacturers know that most people say phase, so rather than to confuse the majority of their customers, they purposely mis label it.

On a side note, playing with polarity reversal is fun! Pick a song, play it in mono with the polarity reversed on one of the channels. Anything center panned will get canceled out, leaving only the artificial reverb trails (or any other effects applied to it that were in stereo).

Dude, that's freakin' awesome... It's so entertaining!

[Ironklad Audio]

Now is that polarity reversal done BEFORE record if it is engaged, or is it something you do AFTER you record. I'd like to do the "gold standard" phase check with all of my mics to get my kit sounding good.

if you're using a software phase reversal, it doesn't matter when you apply it - just like with using a plugin or something, it doesn't change the properties of the waveform that's being recorded - it changes its properties for playback. you can track with the phase flipped, or engage the phase reverse while mixing - either way, it has no effect on the actual .wav file.

if you were using a phase reversal on a preamp/console, then you'd probably want to do so before you track, so that the waveforms are physically recorded with their polarities flipped. of course they can be flipped back again later by using the software phase reversal if need be.

[jrhager84]

So what you're saying is it won't flip on-the-fly? I want to test phase, but if it only applies under AFTER recording, it doesn't help me much...

[MadAudio]

Originally Posted by jrhager84

So what you're saying is it won't flip on-the-fly? I want to test phase, but if it only applies under AFTER recording, it doesn't help me much...

Yes, the polarity reversal is on playback, not record.

[Robert D]

Originally Posted by MadAudio

Yes, the polarity reversal is on playback, not record.

Not if it's on the mic or preamp, as was asked in the OP. Then it certainly is applied during record. And I won't get started on my opinion about it not being phase reversal. I'll just agree that it is not phase delay.

[MadAudio]

Originally Posted by Robert D

Not if it's on the mic or preamp, as was asked in the OP. Then it certainly is applied during record. And I won't get started on my opinion about it not being phase reversal. I'll just agree that it is not phase delay.

Yeah, but we're talking about the software. He already said his hardware has no "phase" button. The question was related to Cubase.

[Robert D]

Originally Posted by MadAudio

Yeah, but we're talking about the software. He already said his hardware has no "phase" button. The question was related to Cubase.

Whoops, sorry. It's a Monday thing.

[mixsit]

Originally Posted by jrhager84

So what you're saying is it won't flip on-the-fly? I want to test phase, but if it only applies under AFTER recording, it doesn't help me much...

If you happen to be doing input monitoring through the app (Q-base) you could.


I figure the reason 'Phase stuck; a) It's easy to say, b) The symbol fits on little buttons.

[MadAudio]

Originally Posted by Robert D

Whoops, sorry. It's a Monday thing.

Not a problem, bro! We're all in this together!

[jrhager84]

Well, I'm horrible at getting my point across, so I'll do my best right now:

If I use Cubase to monitor levels in the mixer window of Cubase, If I hit the snare repeatedly and push the phase button (with monitor button highlighted ONLY, not record) would it reverse the polarity of the signal coming in? Or do I have to actually record a sound to be able to reverse it....if so that's gonna make my life a PITA....

[MadAudio]

Originally Posted by jrhager84

Well, I'm horrible at getting my point across, so I'll do my best right now:

If I use Cubase to monitor levels in the mixer window of Cubase, If I hit the snare repeatedly and push the phase button (with monitor button highlighted ONLY, not record) would it reverse the polarity of the signal coming in? Or do I have to actually record a sound to be able to reverse it....if so that's gonna make my life a PITA....

Originally Posted by MadAudio

Yes, the polarity reversal is on playback, not record.

I think I already answered this....

[mixsit]

Originally Posted by MadAudio

I think I already answered this....

Then you may indeed be right. I'm not in Q'base and just presumed it might work with input monitor engaged.
Did you try it jrhager?

[vadoom]

Originally Posted by IronFlippy

100% correct, listen to this guy. Please get out of the habit of saying "phase" reversal. It's polarity reversal, but manufacturers know that most people say phase, so rather than to confuse the majority of their customers, they purposely mis label it.

On a side note, playing with polarity reversal is fun! Pick a song, play it in mono with the polarity reversed on one of the channels. Anything center panned will get canceled out, leaving only the artificial reverb trails (or any other effects applied to it that were in stereo).

Does it even make sense to "reverse" a phase? All you can do is shift a phase making it it lead or lag...



Stupid marketing making up concepts!!

[Robert D]

Originally Posted by vadoom

Does it even make sense to "reverse" a phase? All you can do is shift a phase making it it lead or lag...



Stupid marketing making up concepts!!

No NO NO!

You guys are just wrong about this. Any common emitter amplifier circuit creates a phase inversion..... not a phase shift, not a polarity inversion...... a phase inversion. Phase, as in "what phase of the cycle is it in?" It's not a marketing mistake that engineers have accepted. The professors that teach electronics, that write the textbooks, didn't start calling it phase inversion or phase reversal because marketing people call it that. It is what it is. It is descriptive of the resultant action. That's why they call it that.

[bennychico11]

uh oh, another phase versus polarity battle!!

do a search. it's been covered a lot around here.

half the people argue that phase invert=polarity reverse
http://homerecording.com/bbs/showthread.php?t=200512

others argue that it's not the same
http://homerecording.com/bbs/showthread.php?t=229125

I'm in the middle now. Each argument is valid but we do worry too much about the semantics of it all. Everyone understands what you're talking about when mentioning phase or polarity switches. The science behind it all is pretty interesting though.

[Ironklad Audio]

If I use Cubase to monitor levels in the mixer window of Cubase, If I hit the snare repeatedly and push the phase button (with monitor button highlighted ONLY, not record) would it reverse the polarity of the signal coming in? Or do I have to actually record a sound to be able to reverse it....if so that's gonna make my life a PITA....

yes, you would be hearing the flipped sine wave by hitting the phase button in cubase, even before recording. we were just trying to make it clear that the track won't actually be recorded with the phase reversal, though...if you disengage the button after recording, it'll go back its "normal" polarity.

[SouthSIDE Glen]

Ugh, here we go again....

Polarity inversion is a flipping of the signal around the 0 DC/centerline axis.

Phase inversion is a flipping of the waveform around itself.

The two are only the same - i.e have the same result - when there is waveform symmetry around the 0 DC centerline.

Any asymmetrical waveform (e.g. a snare hit) will be treated differently by true phase inversion than it will by true polarity inversion. Both will be "inverted" but the overall voltage envelope will be different.

See this post for a graphic illustration demonstrating an extreme example of the difference between phase and polarity..

G.