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Subject:Still No Track Phase switch for AP7
Posted by: BradlyMusic
Date:10/16/2008 10:05:24 AM

At this point.....alls I can say is "WOW!!!". Looking at the picture of AP7 gives some clues of what will be in AP7. So I see they finally added track meters....so my next thing to check out was to look for a track phase switch, and I was amazed to not see a track phase switch button on the track headers. Someone please tell me, I just overlooked it in the picture, because this has just reached the point of ridiculous.

Subject:RE: Still No Track Phase switch for AP7
Reply by: darrena
Date:10/16/2008 11:14:43 AM

You just overlooked it. It's there.

I don't know what it's for, but it's listed.

Switches Including Normalize, Invert Phase, and Lock New!
New track, clip, and event switches in ACID Pro 7 software include Normalize, Invert Phase, Mute and Lock. Use switches to quickly normalize events and perform other processes from within the ACID Pro workspace.

Subject:RE: Still No Track Phase switch for AP7
Reply by: BradlyMusic
Date:10/16/2008 12:28:08 PM

That's good to hear that they added the "event switches".....but it's NOT the same as a track phase button. An event phase switch allows you to switch the phase on the individual clips on a track. Thus, if you had 100 different events on a single track, you would have to set the invert phase switch individually on each event.....where you could rather just enable one button and accomplish that same task with a Track Phase switch.

It's not the same thing, no where near it....a Track phase button and an event phase switch are used for drastically different tasks and the GUI pic does not show a track phase button like you see in Vegas.....where Vegas also has the event phase switch options in addition to a track phase switch.

Thanks for letting me know about the event invert phase addition though. Like you said though, you don't know what it's used for, so it's understandable why you wouldn't know why this is not the same feature as a track phase switch.

Message last edited on10/16/2008 12:30:53 PM byBradlyMusic.
Subject:RE: Still No Track Phase switch for AP7
Reply by: randygo
Date:10/16/2008 1:28:53 PM


Don't panic. It's there:

http://www.sonycreativesoftware.com/images/ss/lg/acidpro7-trackswitches.jpg

Subject:RE: Still No Track Phase switch for AP7
Reply by: BradlyMusic
Date:10/16/2008 5:52:15 PM

Awesome!!

Subject:RE: Still No Track Phase switch for AP7
Reply by: ozzborn
Date:10/20/2008 2:19:58 PM

i got a question, why is track phase important, could you explain how you use it in a mix. thanx in advance

Subject:RE: Still No Track Phase switch for AP7
Reply by: jumbuk
Date:10/20/2008 2:29:39 PM

Why is track phase important?

Simply because you can get unwanted phase cancellation from mics that are positioned close to one another. Reversing the phase can sometimes fix the problem, or at least reveal that there is a problem, so you need to move one of the mics.

Subject:RE: Still No Track Phase switch for AP7
Reply by: ozzborn
Date:10/20/2008 4:22:07 PM

makes sense, if i find loops or sounds that are phasy, i usally use a stero imager and collapse it, i will try phase invert next time. thanx

Subject:RE: Still No Track Phase switch for AP7
Reply by: Chienworks
Date:10/20/2008 8:59:24 PM

Phase inversion isn't intended to fix mic placement problems, nor is it likely to. The chances that mics will be placed exactly half a wavelength different from the subject is very rare, especially since half a wavelength is different for every different frequency. It just ain't gonna happen. Mic placement issues will cause varying phase shift problems all across the frequency band and no phase invert correction will fix it. What *will* fix the problem though is to time shift the track from that mic by sliding the track left or right to bring it back into sync with the other track(s).

What the phase invert button is intended for is cases where the mic's + & - wires are connected backwards. It's rare, but it does happen, especially with home made cables.

Subject:RE: Still No Track Phase switch for AP7
Reply by: Dozza
Date:10/21/2008 1:16:41 AM

Its also used for M/S microphone technique for stereo imaging.
This is a really useful feature and this technique is well worth learning.


Subject:RE: Still No Track Phase switch for AP7
Reply by: BradlyMusic
Date:10/21/2008 7:52:16 AM

"i got a question, why is track phase important, could you explain how you use it in a mix. thanx in advance"

MS Micing is one good use of a track phase reverse switch.

Also, time alignment of 2 similar audio tracks is another. Lets say for example, you recorded 2 tracks on different sources, say a Camera mic and then to a DAT, or other digital storage device. Usually the Camera mic will be the worse quality of the 2 recordings, but it will be the one that is in sync with the video. So the task at hand would be to put the better quality audio in sync with the video. So it is easier for our ears to hear when audio is 180 degrees out of phase then it is to tell when it is perfectly in phase. So what you do, is temporarily phase reverse one of the tracks until you hear the most phase cancellation occurring between the 2 tracks....then once you hear the time alignment with the most phase cancellation, you then turn the phase reverse switch off, which means the 2 tracks will now be in phase and in sync with the video.

Microphones made by different manufacturers are sometimes out of phase also with each other. For instance I have found in the past that Seinheiser mics are 180 degrees out of phase with Shure mics. So if you are using 2 mics on the same source, you sometimes need to flip the phase on one of the tracks so that they are actually in phase with each other, otherwise your multiple micing will sound like crap, and not what you had expected.

When doing Multiple micing recordings and doing them "right", a phase reverse switch is a necessity. Let's say you are micing a drum set...more specifically a snare drum, with a mic on the bottom of the snare drum and a mic on the top of the snare drum. The mic on the bottom is 180 degrees out of phase with the mic on the top due to the actual physics of the sound. No crossed wires, No mics out of phase with each other in this instance. To blend/mix those mics together you will have to reverse the phase of the mic on the bottom.

Additionally, in that same drum micing, you will have a mic on the Toms, kicks, and overheads. So you will have 8 or more mics at different locations and spread apart from each other. Sound from the toms will bleed into the kick drum, the kick drum sound will bleed into the overhead mics....etc. When you mix all these drum mics together, there will be some type of phase cancellation, since the mics are not located at the same place. So ideally what you want to do is time align all the mics. There is approximately a 1mS delay for every 1ft. that each mic is separated from each other. So what you do is add a delay, on each track and adjust for the distance that each mic is separated. Like I mentioned earlier......it is easier for your ears to detect when there is the most phase cancellation compared to being able to hear when they're perfectly aligned....so again when time aligning 2 of the drum mics you would phase reverse one of the tracks, then add a delay plugin to it or shift that track along the time line in small amounts. You then start adjusting the delay/track nudge and find the delay amount where you hear the most phase cancellation....then when you've found that delay amount you turn the phase reverse switch off, to put the 2 mics back into phase with each other. Then you would move onto the next drum mic track and do the same thing, until you have all 8 tracks in phase with each other, and in the end you will end up with a much clearer recording with minimal phase cancellation between the all the drum tracks.

Basically, anyone that knows anything about doing proper multiple micing recordings needs a phase reverse button. It's really not about wrongly wired cable fixes, although those do exist also.

If you do any surround mixing and use a stereo music source in your surround project you will need a phase reverse button. With music you will want to put the Left channel into the L/F speaker and the Right channel in the R/F speaker.....additionally you will want to put a (Left - Right) into the Left surround speaker and (Right - Left) into the right surround speaker by using a phase reverse button to achieve the Left-Right and Right-Left.


"Phase inversion isn't intended to fix mic placement problems, nor is it likely to."

Yes, it is....but just not in the over simplified manor that you are describing. You could even benefit from a phase reverse button in the track time alignment that you described if you knew how to properly use it and knew a little about how we hear sound.

Message last edited on10/21/2008 8:22:49 AM byBradlyMusic.
Subject:RE: Still No Track Phase switch for AP7
Reply by: deusx
Date:10/21/2008 9:28:44 AM

>>>Basically, anyone that knows anything about doing proper multiple micing recordings needs a phase reverse button. <<

Or they could just place microphones ( or use proper mics ) so they sound good in the first place.

I mean, who the hell starts recording before testing it and making sure it sounds good. Therefore phase reverse = pretty much useless.


Subject:RE: Still No Track Phase switch for AP7
Reply by: Patrick@Denman
Date:10/21/2008 10:53:18 AM

I mean, who the hell starts recording before testing it and making sure it sounds good. Therefore phase reverse = pretty much useless.

It's hard to conceive of anyone who has actually had experience recording a multi-instrument band or has had to record in a less-than-perfectly-isolated space who would make a statement like that.

If every single track of your recording is made in an acoustically isolated studio, one instrument or performer at a time, then you wouldn't likely need phase reverse. But it sure as hell comes in handy in most other situations.

Subject:RE: Still No Track Phase switch for AP7
Reply by: Chienworks
Date:10/21/2008 11:40:27 AM

"Yes, it is....but just not in the over simplified manor that you are describing. You could even benefit from a phase reverse button in the track time alignment that you described if you knew how to properly use it and knew a little about how we hear sound."[\i]

I humbly suspect that i know more about it than you can imagine. ;) But, anyway ...

Your description involves using phase inversion to diagnose the problem, not to fix it. You're still using time displacement to perform the fix.

Also, please avoid using the phrase "180 degrees out of phase" in relation to phase inversion. They have absolutely nothing to do with each other. They only seem related when dealing with very simple mono-frequency waves like a pure sine, triangle, or square wave. Even in those cases they're not the same thing, they just appear to be. 180 degrees out of phase means that the wave form has been shifted in time half the wavelength, which is rather meaningless in a complex wave form. Phase inversion means that the wave has been flipped +/- and is always applicable no matter how complex the sound is.

Subject:RE: Still No Track Phase switch for AP7
Reply by: BradlyMusic
Date:10/21/2008 11:53:58 AM

"Or they could just place microphones ( or use proper mics ) so they sound good in the first place.

I mean, who the hell starts recording before testing it and making sure it sounds good. Therefore phase reverse = pretty much useless."

Most ignorant statement of the year. Read my examples that I've given and see this has nothing to do with proper mics, or proper mic placement. This has to do with the physics of sound. Sound travels at 1128 ft/sec....which means if you use multiple mics, placed at different locations within a room, the same sound will not arrive at each mic at the same time. Thus, when you mix those mic signals together within a multitrack environment phase cancellation will occur.

You obviously have no knowledge in this matter, so save yourself some embarrassment and refrain from making further ignorant statements.


Message last edited on10/21/2008 11:58:23 AM byBradlyMusic.
Subject:RE: Still No Track Phase switch for AP7
Reply by: BradlyMusic
Date:10/21/2008 12:07:12 PM

"Your description involves using phase inversion to diagnose the problem, not to fix it. You're still using time displacement to perform the fix."

Read it again, and this time try to understand it. Yes, I didn't use phase reverse to fix the problem, but it was an essential tool to get to the proper solution. When I fix the brakes on my car, the wrench I used does not fix the brakes either, but it is an essential tool to make certain that I fixed them properly.


"I humbly suspect that i know more about it than you can imagine. ;) But, anyway ..."

You're certainly not sounding as smart as you think your are. You must be one of the reasons why Acid has gone this long without a phase reverse button on tracks. You obviously, show very little knowledge in the use of a phase reverse track function.

Subject:RE: Still No Track Phase switch for AP7
Reply by: jumbuk
Date:10/21/2008 4:39:12 PM

My god! I never suspected that my short answer would provoke this kind of exchange.

Fact is, engineers have been using the phase reversal switch to check ("diagnose") mic placement problems for years. No, it doesn't generally fix the problem, and you generally have to move the mic to fix it (as I think I said).

Someone said (I paraphrase) that it's too late to fix it in the mix if phase cancellation has happened. That's the whole point - you are trying to pick up an issue before you record and fix it by moving mics.

However, I do agree that the button is no big deal in Acid. I am hardly going to be recording a multi-mic setup without a hardware mixer somewhere earlier in the chain.

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