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[Jonathan Johnson]

With powered speakers all using different varieties of DSP, their latency can vary to the point where "proper" connection will not insure different models will either be in phase, or even in the same polarity.

With two passive speakers being fed the same signal, what you hear won't be "in phase" depending on your listening point, due to the speed of sound and your distance from each speaker. So if the coverage areas don't overlap, polarity isn't that important. And as far as the driver moving inward or outward on the initial strike of the drumhead, that's going to affect whether the eardrum moves inward or outward on that strike. But when the ear and brain process sound, they don't really differentiate between the eardrum moving inward or outward.

HOWEVER, that drum strike *may* be perceived by the body as a compressive force, and a compressive force (from the driver moving outward) will certainly have a different effect than a rarefying force (from the driver moving inward). But even if the polarity is reversed so the initial strike is rarefying, when the speaker returns to the zero volts position there should be an equal reactionary but compressive force. The difference in polarity may not be noticeable; this is speculation on my part and perhaps a blind test would be appropriate.

[David Allred]

So...
1) a single driver or cabinet moving in or out (based on a signal in or out of normal "phase") is mute except for the most critical aspects of analysis?

2) a signal with reversed hot / cold wiring will yield a reverse acting cone?

3) a signal with reversed hot / cold wiring AND reversed speaker wiring will yield a correctly moving cone?

[Jerome Malsack]

With two passive speakers being fed the same signal, what you hear won't be "in phase" depending on your listening point, due to the speed of sound and your distance from each speaker. So if the coverage areas don't overlap, polarity isn't that important. And as far as the driver moving inward or outward on the initial strike of the drumhead, that's going to affect whether the eardrum moves inward or outward on that strike. But when the ear and brain process sound, they don't really differentiate between the eardrum moving inward or outward.

HOWEVER, that drum strike *may* be perceived by the body as a compressive force, and a compressive force (from the driver moving outward) will certainly have a different effect than a rarefying force (from the driver moving inward). But even if the polarity is reversed so the initial strike is rarefying, when the speaker returns to the zero volts position there should be an equal reactionary but compressive force. The difference in polarity may not be noticeable; this is speculation on my part and perhaps a blind test would be appropriate.

So it would make a difference based upon if the drum (large base drum) is laying flat and struck up and down, or standing and struck from side to side.   If the speaker or drum is side to side its sound would be figure eight based on the way it is setup.   If the speaker is a monitor the polarity would affect the playback if one likes David Ratts view on drums and monitors. 

http://www.prosoundweb.com/article//not_so_mysterious_using_polarity_as_another_tool_for_optimizing_drum_sound/

When the base drum is horizontal the pattern should be figure eight but I have not seen test results as to the effects of the bottom lobe being close to the floor and the effect it would have on the pattern. 

[Ivan Beaver]

So...
1) a single driver or cabinet moving in or out (based on a signal in or out of normal "phase") is mute except for the most critical aspects of analysis?

2) a signal with reversed hot / cold wiring will yield a reverse acting cone?

3) a signal with reversed hot / cold wiring AND reversed speaker wiring will yield a correctly moving cone?

I get the feeling you are thinking a cone either moves in or out.

It moves the same in both direction-depending on whether it is pos or neg at the particular time.

1) I don't get it

2) Yes when you flip the polarity the cone direction will change.

3) It depends on what you call "correct".  As Art mentions the actual movement could be a tossup in direction due to all the "changes" along the way.

[Jonathan Johnson]

When the base drum is horizontal the pattern should be figure eight but I have not seen test results as to the effects of the bottom lobe being close to the floor and the effect it would have on the pattern.

Whether the bass drum is spinning circles and dancing the cha-cha in your grandmother's basement is irrelevant, since the OP was asking about a media player rather than live sounds. So whether the drum strike moves the cone initially inward or outward only affects perception, and that probably minimally, ASSuming that the microphone was placed facing the "audience" side of the drum and was wired observing polarity standards throughout the entire signal chain to the final product. With the microphone placed in any other location, it's anybody's guess.

[Ivan Beaver]

So it would make a difference based upon if the drum (large base drum) is laying flat and struck up and down, or standing and struck from side to side.   If the speaker or drum is side to side its sound would be figure eight based on the way it is setup.   If the speaker is a monitor the polarity would affect the playback if one likes David Ratts view on drums and monitors. 

http://www.prosoundweb.com/article//not_so_mysterious_using_polarity_as_another_tool_for_optimizing_drum_sound/

When the base drum is horizontal the pattern should be figure eight but I have not seen test results as to the effects of the bottom lobe being close to the floor and the effect it would have on the pattern.

I have a real problem with the "idea" of that article.

The "idea" being that the mics and the monitor speaker will be "in phase" and helping to setup feedback-or resonance.

HOWEVER that only happens at a SPECIFIC distance and SPECIFIC freq.

At a particular freq the pressure will be plus and neg-depending on the distance from the source.  So move either the mic or the speaker and the "phase alignment" will change. 

I do agree that flipping the polarity (not to a particular position-but simply changing ) MAY help reduce the addition OR make it worse.  And depending on the actual relationship of speaker and mic, it may not make any difference-if the phase is 90°out.

The idea that it is as "simple" switching the polarity will make it better.  It really is a "crap shot" as to whether or not it will get better or worse or make no difference-at least in my experience.

[Steve M Smith]

Perhaps if the speed of sound was closer to the speed of light...


Steve.

[David Allred]

I get the feeling you are thinking a cone either moves in or out.

It moves the same in both direction-depending on whether it is pos or neg at the particular time.

1) I don't get it

2) Yes when you flip the polarity the cone direction will change.

3) It depends on what you call "correct".  As Art mentions the actual movement could be a tossup in direction due to all the "changes" along the way.

Me brain fart.  Me clarify.

1) "Mute" should read "moot".

3) "Correct" as in moving out when +v is applied.  For example...
a - signal recorded "in phase"
b - output at play devise - in phase
c - connection cable mis-wired so signal is out of phase at amp input
d - signal in amp - out of phase
e - amplified signal exiting amp - out of phase
f - speaker cable connections switched + to -, - to +

Is the cone movement direction correct to the intent of the recording?

In the context of this discussion, are phase and polarity referring to the same thing?

Am I wrong in saying that phase is the result, but polarity is the cause... since wiring is the topic?

Which is correct? 
Polarity can only be 0 deg & 180 deg.
or
Polarity is any 180 deg differential.  (10 & 190, 90 & 270, etc)

Last stupid question:
If a signal is sent through 2 disproportionately lengthed cables to an amp / speakers, will the output be produced out of phase to each other?  To what extent?  1' vs 100', 1' vs 1000', 1' vs 10,000'?

I love the smell of minutia in the morning.
Thanks for all the discussion.

[Steve M Smith]

Last stupid question:
If a signal is sent through 2 disproportionately lengthed cables to an amp / speakers, will the output be produced out of phase to each other?  To what extent?  1' vs 100', 1' vs 1000', 1' vs 10,000'?

Which comes back to my speed of light comment!

Yes - but you won't notice it and I doubt that you have the equipment to measure it.


Steve.
 

[John Roberts {JR}]

In the context of this discussion, are phase and polarity referring to the same thing?

Probably.

Am I wrong in saying that phase is the result, but polarity is the cause... since wiring is the topic?

No.. phase is phase and polarity is polarity.

Which is correct? 
Polarity can only be 0 deg & 180 deg.
or
Polarity is any 180 deg differential.  (10 & 190, 90 & 270, etc)

Neither, Polarity is either Positive (correct) or Negative (opposite) . The 180' phase shift only resembles opposite polarity for sine waves, for complex waveforms phase shift has little meaning.   

Last stupid question:
If a signal is sent through 2 disproportionately lengthed cables to an amp / speakers, will the output be produced out of phase to each other?  To what extent?  1' vs 100', 1' vs 1000', 1' vs 10,000'?

Delay time will be insignificant in the context of audio frequency phase shift.

JR

I love the smell of minutia in the morning.
Thanks for all the discussion.

[ProSoundWeb Community]