CD-E5 "Phase Invert"

Does anyone know exactly what "phase invert" means? And more specifically, actually what it does when selected on the E5?

I did a search, but the only thread the term "E5" and "phase invert" is found in is that monster of a thread ("thinking about picking up an E5"). If my question is addressed in that thread, could someone kindly let me know exactly what page it's on?

Thanks.

The links below will give you an idea:

http://www.gcaudio.com/resources/how...lutephase.html

Getting used to hearing out of phase, or more accurately, reverse polarity, is just a matter of carefully listening and knowing what to listen for. The easiest thing to hear is bass and drums, which will tend to sound diffuse, blurred, or unfocused. Much of this, if not all, has to do with the speaker cone moving backwards, when it should be moving forward. This phenomenon has actually been written about by an audio enthusiast named R.C. (better known as Clark) Johnsen , in a book called The Wood Effect: Unaccounted Contributor to Error and Confusion in Acoustics and Audio, The Modern Audio Association. Boston, 1988.

http://www.positive-feedback.com/Iss...woodeffect.htm

The problem with many recordings, is that they are recorded with mixed polarity (absolute polarity = 0 and reverse polarity = 180), so some portions will sound correct, while others do not. All you need to screw up, is a microphone that has been incorrectly wired, when recording an album. If you have the fairly recent 2 disc The Complete Africa Brass Sessions by The John Coltrane Quartet, on Impulse, listen to the difference in the bass with absolute polarity and reversed - you will be shocked.

It's very easy to detect reversed phase between two channels... the positive and negative reversed on one channel. The two channels pull against each other, cancelling out a lot of the sound. However it is impossible to detect inverted phase on both channels... the positive and negative reversed on both channels, because the two channels are syncronized.

Though some claim they can hear the difference, science, logic and the old dreaded "test which dare not utter its own name" proves them wrong. Think about it... a speaker producing a 100Hz tone is vibrating in and out 100 times a second. The difference between inverted phase on both channels would be 1/200th of a second. It's hard enough for the ear to detect directionality on notes that low, much less timing with that sort of precision. You'd be assuming that a speaker begins to produce sound with the very first movement of the cone, and that a single excursion could be heard in a normal listening room. In headphones the effect would be even less likely because the two channels would be completely isolated from each other in the ear cups. It's more difficult to hear reversed phase between the two channels in cans, much less inverted phase in both channels... especially since the distance of the excursion is so much smaller in headphones.

There used to be a chart posted here listing record labels and whether they were positive or reverse phase. That was completely absurd, because it assumes that every studio and mastering facility used to record for a particular label is rewired depending on which label they're recording for.

See ya
Steve

Inverting polarity makes a significant difference in sound. I'm sorry you can't hear it.

i believe inverted phase makes no difference in sound, indeed many dacs have inverted phase

Some people believe that absolute phase (or polarity) matters a great deal. I haven't heard of CD players that invert the phase. Usually for audio purposes whether or not a piece of equipment inverts phase is usually listed for amps and preamps.

Each gain stage that a piece of equipment has inverts the phase. What this means is that if there is an odd number of gain stages the equipment will invert the phase. If your preamp inverts phase and your amp does as well (most CJ equipment) your system will maintain absolute phase.

The CD-E5 has a tube output so I wouldn't be surprised if it does invert polarity. The I/E has correct phase then that might go to the tube stage that would invert the phase. I don't know the CD-E5 so this is just conjecture.

Some people claim to hear a difference. Since it is easy to maintain a systems absolute polarity (or phase) I choose to do so. Can I hear a difference, never tried and I don’t care.

I've written before about my Cyrus CD6 having phase invert and how I can definitely tell the difference with a lot of recordings. With my EMU1212M using the phase invert causes no change. Difference in the quality of the components? Or does the Cyrus do something "more". I'd be put to the blind test any day with my Cyrus with no problem.

If the recording is good, the soundstage goes out (but not in a good way), and the bass disappears. If the recording is reversed, the opposite happens.

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The Eastsound does not have tubed output.

From what I've been told, they added the phase invert so that you could quickly correct any problems with the balanced outputs since some XLR cables are wired opposite to standard in Asia.

I got my players confused.

The phase invert switch is used because some recordings are thought to be out of phase.

If you really want to get insane about phase check out a book called:

The Wood Effect by Clark Johnsen
The book was available in the 90's at: Clark Johnsen’s book The Wood Effect, is available from: The Modern Audio Association, 23 Stillings Street, Boston, MA 02210; Tel: 617/357-8040.

Inverting phase means flipping the signal upside down. This is the same as a time delay for continous waveforms such as the pure tone in bigshot's post. However, dynamic spikes will be clearly represented differently. For instance, hitting a drum will cause a large, quick spike in the time domain. Playing this through a speaker normally will cause the cone to push out at you very quickly. If you play it through the speaker inverted, the cone will actually suck in instead of pushing out and you will miss the impact. All this said, I personally have difficulty hearing the difference in most cases.

The invert button is to correct for absolute phase. A description about phase inverting is found here:

http://www6.head-fi.org/forums/showthread.php?t=89043

a list of labels that typically have inverted phase is found here:

http://home.comcast.net/~theaudioana...e_Polarity.htm

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What frequencies are you talking about? The higher the frequency, the more excursions back and forth per second, and the less chance that the slight time shift would make any difference at all. For instance, a snare drum which lives in the 5kHz neighborhood would be an offset of 1/10,000th of a second. The impact of the hit is not even close to being that fast. It wouldn't be affected at all. A kettle drum hit is so broad, timewise it wouldn't be affected either. Besides, inverted phase doesn't mean that the speaker won't produce the sound... it just means that the timing of it is off. If both speakers are off in the exact same way, there is no difference.

If you do the math, the issue of absolute phase just doesn't stand up. It's fine if someone wants to think they hear a difference, but it doesn't mean they have better hearing any more than saying "I see dead people" means they have better eyesight.

See ya
Steve

*Dumps a big bucket of snake oil on bigshot*

Wait, so Jeff can hear phase differences in percussive passages... but if 'he does the math' he will see this is false?

You don't need math to comprehend that the same event played with air moving forward and air being drawn backward will be different. Perhaps an analogy might be help: try to say the word press normally and then while inhaling - not quite the same but conceptually you get the idea.

It's possible some people may not hear this easily because their speakers may not be phase coherent or they're not sure what to listen for in the recording. Here's something you can listen to for yourself. If you have the 1997 reissue of Alfie by Sonny Rollins (IMPD-224) play cut 6, Alfie's Theme Differently - with the polarity inverted, the sound of Rollins' horn recedes and almost sounds like the notes are behind the sound of his keys clacking. When you listen without inversion, the horn notes come forward and clearly have more dimension.