Speaker Polarity

Archived from groups: rec.audio.tech (More info?)

Paul,

> So, with speakers in phase, are there some types of two-wire speaker that
are sensitive to polarity? <

It seems the question you're asking is if absolute polarity (not the same as
phase) is audible, yes?

There's a discussion about this going on right now in the rec.audio.pro
newsgroup. As far as I'm concerned it is *not* audible. It's possible to
contrive tests that show an audible difference, but those are irrelevant
because they rely on playing frequencies below the speaker's cutoff where
the speaker behaves non-linearly. So in that case it's the *speaker* that's
responding differently to each direction. This is not the same as your ears
being able to hear a difference with reversed polarity.

--Ethan

Archived from groups: rec.audio.tech (More info?)

>Paul,
>
>> So, with speakers in phase, are there some types of two-wire speaker that
>are sensitive to polarity? <
>
>It seems the question you're asking is if absolute polarity (not the same
>as
>phase) is audible, yes?
>
>There's a discussion about this going on right now in the rec.audio.pro
>newsgroup. As far as I'm concerned it is *not* audible. It's possible to
>contrive tests that show an audible difference, but those are irrelevant
>because they rely on playing frequencies below the speaker's cutoff where
>the speaker behaves non-linearly. So in that case it's the *speaker* that's
>responding differently to each direction. This is not the same as your ears
>being able to hear a difference with reversed polarity.
>
>--Ethan
>
>
>

However, a Sheffield Lab recording of a piano (Lincoln Mayorga) instructed the
user to reverse the polarity on the playback speakers. It made a difference,
but it's been so long ago thqat i can't remember the results.
Richard H. Kuschel
"I canna change the law of physics."-----Scotty

Archived from groups: rec.audio.tech (More info?)

On 07 Jul 2004 19:07:05 GMT, rickpv8945@aol.com (Richard Kuschel)
wrote:

>However, a Sheffield Lab recording of a piano (Lincoln Mayorga) instructed the
>user to reverse the polarity on the playback speakers. It made a difference,
>but it's been so long ago thqat i can't remember the results.
>Richard H. Kuschel
>"I canna change the law of physics."-----Scotty

Why? Did they record it out-of-phase by mistake?

Archived from groups: rec.audio.tech (More info?)

On Wed, 7 Jul 2004 18:34:56 -0400, "Arny Krueger" <arnyk@hotpop.com>
wrote:

>The dynamic range of LPs is asymmetrical. You can only go up to surface
>level in the vertical direction, but you can dig a deeper hole. AM radio is
>the other way around.
>

Explain, please?

My visualisation is that loud bass will make the stylus ride lower.
Why would absolute phase make a difference?

Archived from groups: rec.audio.tech (More info?)

anybody-but-bush wrote:

> "Paul Harris" <news@ehteam.screaming.net> wrote in message
> :
> : and one reply was:
> :
> : "uhh man... thats bad... it does matter whith one!
> : your way you could get speakers in phase but running other way around
> : (plus to minus) so instead speaker blowing out like this: <- D it would
> : go like this: -> D.
> : you probably would notice it as it would produce distortion on high volume.
>
> An age old fuel source for flame wars.
> 1) the recorded signals of musical instruments,etc are not symmetrical.(fact)
> 2) some people claim to be able to tell which is true to the source and vice verse.
> 3) some people claim not to be able to tell is was is true to the source and vice verse.
> 4) multitracked recordings where a source sound is picked up by more than one mic obscure this
> phenomenon .

Thanks to everyone who has shed light on this and apologies for fanning
old flames.

I had not considered symmetry. The "distortion on high volume" got me
wondering if there are speakers that oscillate around a voltage other
than zero i.e. the natural rest position on the cone is different from
the powered but silent position in which case when switched on, the cone
would be seen to jump forward (or back) and hold due to a non-zero
voltage being applied.

Since nobody has mentioned this, I guess there would be no advantage in
such a design - there is no need to "park" a speaker when powered off
like a hard disk drive head.

Archived from groups: rec.audio.tech (More info?)

On Wed, 7 Jul 2004 21:05:46 -0400, "Arny Krueger" <arnyk@hotpop.com>
wrote:

>"Laurence Payne" <l@laurenceDELETEpayne.freeserve.co.uk> wrote in
>message news:6h0pe0pss29imqcrcn8dgpucitj02ndbiu@4ax.com
>> On Wed, 7 Jul 2004 18:34:56 -0400, "Arny Krueger" <arnyk@hotpop.com>
>> wrote:
>>
>>> The dynamic range of LPs is asymmetrical. You can only go up to
>>> surface level in the vertical direction, but you can dig a deeper
>>> hole. AM radio is the other way around.
>
>> Explain, please?
>
>> My visualisation is that loud bass will make the stylus ride lower.
>
>If the music is a symmetrical wave, the average height of the stylus will be
>unchanged.
>
>Not surprisingly, positive Y on a LP is up. That means that a cartridge with
>positive polarity will produce a positive signal when the stylus is moving
>up.
>
>> Why would absolute phase make a difference?
>
>Stylus movement in the up direction is limited by the zero signal depth of
>the groove.
>
>Natural music and voice is often asymmetrical. It often has the greatest
>peak amplitude in the positive direction. However, the greatest peak
>amplitude that can be recorded on a LP is less in the positive direction
>than the negative direction.
>
>If a record is cut with inverted polarity and played with reversed
>connections on the cartridge, then the signal will have positive polarity,
>but the largest peaks will be in the down direction.
>
>This whole argument is based on a very simplistic or purist view of
>allowable signal processing. But in the context, purist approaches would be
>expected.
>
>
Thank you

Archived from groups: rec.audio.tech (More info?)

Paul Harris wrote:
>
> anybody-but-bush wrote:
> >
> > An age old fuel source for flame wars.
> > 1) the recorded signals of musical instruments,etc are not symmetrical.(fact)
> > 2) some people claim to be able to tell which is true to the source and vice verse.
> > 3) some people claim not to be able to tell is was is true to the source and vice verse.
> > 4) multitracked recordings where a source sound is picked up by more than one mic obscure this
> > phenomenon .
>
> Thanks to everyone who has shed light on this and apologies for fanning
> old flames.


A legitimate question, none-the-less (although its flamed past
may have relegated it a spot in the FAQ :-)


> I had not considered symmetry. The "distortion on high volume" got me
> wondering if there are speakers that oscillate around a voltage other
> than zero i.e. the natural rest position on the cone is different from
> the powered but silent position in which case when switched on, the cone
> would be seen to jump forward (or back) and hold due to a non-zero
> voltage being applied.


The only place that I have seen this is when an amplifier has a
DC component on its output (not good). This not only has the
speaker dissipating power when there is no sound being produced
(hey! That would make it a "class A" speaker! :-), it now puts
the operating point on the speaker such that it can limit in one
direction befor it limits in the other.


> Since nobody has mentioned this, I guess there would be no advantage in
> such a design - there is no need to "park" a speaker when powered off
> like a hard disk drive head.


There might be such an advantage on more exotic speaker designs
that are attempting to utilize some other principles in
operation, but the speaker would need its own (matched) power
circuitry to ensure that the zero point of the transducer element
was matched to the zero point of the driving electronics. It
would not be so much a need to "park" the transducer when off as
the need to optimize its zero point when in operation. I don't
know of any transducer types that do this but that doesn't mean
there aren't any.

On a normal speaker, the unpowered reference point naturally
falls in the middle of the speaker's normal travel range (like a
spring that has neither been compressed or stretched). No current
applied, speaker is at reference point. Positive current applied,
speaker moves out from reference. Negative current applied,
speaker moves in from reference (sorta like a "class B" operation :-)

Since the farther you move away from the reference point, the
closer you approach the speaker's physical limits and the greater
the possibility of operating in non-linear regions of the
speaker's travel. If the non-linear areas were not symmetrical
about the rest position, then conceptually applying a DC offset
to "center" the operation between the non-symmetric areas might
seem feasible. However, it would appear to me that the complexity
of doing this could be orders of magnitude above that of just
designing the transducer so that it is symmetric and linear in
both directions (i.e., the current phylosophy of most speaker
driver design)

- Jeff

Archived from groups: rec.audio.tech (More info?)

>
>On 07 Jul 2004 19:07:05 GMT, rickpv8945@aol.com (Richard Kuschel)
>wrote:
>
>>However, a Sheffield Lab recording of a piano (Lincoln Mayorga) instructed
>the
>>user to reverse the polarity on the playback speakers. It made a difference,
>>but it's been so long ago thqat i can't remember the results.
>>Richard H. Kuschel
>>"I canna change the law of physics."-----Scotty
>
>Why? Did they record it out-of-phase by mistake?
>
>
>
>

Nothing was out of phase.
They had recorded the piano with both channels in reversed polarity, which is
why they suggested reversing the leads on both speakers. Of course, this
assumes that the listener's playback system maintains absoulte polarity, which
may or may not be the case.

Since this was a direct to disc recording, the polarity error could not be
reversed before printing the final discs.
Richard H. Kuschel
"I canna change the law of physics."-----Scotty

Archived from groups: rec.audio.tech (More info?)

ChrisCoaster wrote:

> "Ethan Winer" <ethanw at ethanwiner dot com> wrote in message news:<xr6dnYY7IcpSlXHdRVn-jA@giganews.com>...
>
>>Paul,
>>
>>
>>>So, with speakers in phase, are there some types of two-wire speaker that
>>
>>are sensitive to polarity? <
>>
>>It seems the question you're asking is if absolute polarity (not the same as
>>phase) is audible, yes?
>>
>>There's a discussion about this going on right now in the rec.audio.pro
>>newsgroup. As far as I'm concerned it is *not* audible. It's possible to
>>contrive tests that show an audible difference, but those are irrelevant
>>because they rely on playing frequencies below the speaker's cutoff where
>>the speaker behaves non-linearly. So in that case it's the *speaker* that's
>>responding differently to each direction. This is not the same as your ears
>>being able to hear a difference with reversed polarity.
>>
>>--Ethan
>
> ____________________________
> I would think there would be an impact of absolute phase on
> transients(drums, Tchaikovsky's cannon, cymbols, xylophones, etc.).
> But not so much on constant waves(pianos, organs, sustained guitar
> notes, vocals, etc.) So it is possible that the drums may lack some
> clarity or snap, depending on how they were tracked in studio.
>
> For me, I want my woofers and mids to push toward me when reproducing
> transients, not away.
>
> -CC

Then you need to control the microphones and the entire recording chain.

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form che...@prodigy.net.

Archived from groups: rec.audio.tech (More info?)

CJT <abujlehc@prodigy.net> wrote in message news:<40F4204B.2040907@prodigy.net>...
> ChrisCoaster wrote:
>

> >
> > ____________________________
> > I would think there would be an impact of absolute phase on
> > transients(drums, Tchaikovsky's cannon, cymbols, xylophones, etc.).
> > But not so much on constant waves(pianos, organs, sustained guitar
> > notes, vocals, etc.) So it is possible that the drums may lack some
> > clarity or snap, depending on how they were tracked in studio.
> >
> > For me, I want my woofers and mids to push toward me when reproducing
> > transients, not away.
> >
> > -CC
>
> Then you need to control the microphones and the entire recording chain.
________________
Yikes! Didn't thinka that one. Yeah, polarity's probably been
flipped more times from studio to mastering than pancakes in a Pancake
House. Familiar with the complications of miking an open-ended
snare drum?

Still, at least if my end is confirmed correct polarity - any *flaws*
intentional or incidental would shine through.

-CC