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Reverse polarity on speakers (not out of phase)

allthingsanalog

pfm Member
Does anyone have any experience connecting their speakers with the pos and neg reversed, not so they out of phase with each other with both the same?

I have a room with terrible bass problems and even Royd Edens used to boom a bit.

My Spendor S3/5R2 seem to perform with a tighter bass this way and i feel they sound even more open and spacious.

I remember Audiolab many years ago reccomending this way when using some Ruark speakers.
 
Speakers with second order crossovers will already have the tweeter and mid/bass wired in opposite polarity relative to each other and absolute polarity is seldom considered when recordings are made so one instrument is likely to be in opposite absolute phase relative to others - in other words, it doesn't really make any difference. If you have room gain problems (room boom), then altering the relative polarity won't change that.
 
Speakers with second order crossovers will already have the tweeter and mid/bass wired in opposite polarity relative to each other and absolute polarity is seldom considered when recordings are made so one instrument is likely to be in opposite absolute phase relative to others - in other words, it doesn't really make any difference. If you have room gain problems (room boom), then altering the relative polarity won't change that.

Really? I'd have thought that where they are producing the same frequency (or overlapping harmonics) it would have.

Not saying you're wrong, as I simply don't know, just hypothesising.

However, I imagine you're absolutely spot on that changing overall polarity will make the square root of diddly squat difference to room node issues.
 
How can the polarity get swapped in a recording studio?

I can tell if the cones are going backwards then forwards rather than forwards then backwards.

Try it for yourself and make your own mind up.

Pete
 
How can the polarity get swapped in a recording studio?

I can tell if the cones are going backwards then forwards rather than forwards then backwards.

Try it for yourself and make your own mind up.

Pete

Aren't they kinda mostly just going one way then the other?
 
How can the polarity get swapped in a recording studio?

By using the track polarity reversal button helpfully provided on the mixing desk.

It's there because you can't rely on the wiring to microphones, etc., to conform to any standards, and you might also like the effect. It allows noise cancellation too if you use two microphones next to each other wired in opposite sense. The Grateful Dead used such live on stage to avoid acoustic feedback from their mahoosive speaker systems.
 
Changing phase won't change fundamental room problems. These are primarily dictated by the room dimensions
 
But it might slightly soften bass and drum transients if they come out of the speakers as "suck" rather than "blow"

Phase inversion is definitely audible which is why a lot of pro equipment is equipped with an invert feature.
 
But it might slightly soften bass and drum transients if they come out of the speakers as "suck" rather than "blow"

Phase inversion is definitely audible which is why a lot of pro equipment is equipped with an invert feature.

I would suggest that a speaker that has issues with the driver moving in one Particular direction may not be of the best design.....it's a bit of a fundamental requirement unless you want massive distortion. A transient won't just go in "one direction" btw, do a search on drum waveform images. Also, as mentioned, the absolute polarity of any recoded instrument won't be guaranteed.

Anyhow, what the op describes is a room problem. It's not going to be solved by phase swapping.
 
Pete,

How can the polarity get swapped in a recording studio?
It happens when a sucky band is booked for a session, but instead of sucking it turns out they blow.

Joe
 
Baz,

If you look closely enough, you'll see that every post is a Star Trek post, you Denebian Slime Devil!

Joe
 
Better than the endless 'my dac* is better than your dac*' posts...

*insert whatever flavour of the month bit of tech that's going to "transform" your listening experience...
 
When I rebuilt Andrew's Linn Sara's I found that the tweeters were wired in opposite relative phase to the mid/woofers which makes sense being 2nd order crossovers. However, the unusual bit was that the woofers were the ones wired in negative phase (in other words they moved in on a + signal and out on -) rather than the tweeters.
 
When I rebuilt Andrew's Linn Sara's I found that the tweeters were wired in opposite relative phase to the mid/woofers which makes sense being 2nd order crossovers. However, the unusual bit was that the woofers were the ones wired in negative phase (in other words they moved in on a + signal and out on -) rather than the tweeters.

That's how the classic Tannoys do it too IIRC. Never understood why. I just tend to try and set it as the manufacturer intends - if I know I'm using a phase inverting amp, e.g. a Quad 303, then I'll hook it up black to red.

Odd subject absolute phase. I do think it makes a (very small) difference. I've a fair few components where I don't know if they phase invert or not, e.g. Verdier tube pre, Leak Stereo 20 or which driver is 'in' on the JR149s, and don't even start me on the Klipsch La Scalas - a bass driver pointing backwards into a horn and then a mid horn and tweeter with the motors about a foot and a half apart front to back?! I'll just assume PWK knew what he was doing there...
 
Some LP/CD's are recorded in reversed phase and sound much better when you change the polarity. One example I know of is Lou Reed's wonderful New York album (1989).
 
Phase inversion is definitely audible which is why a lot of pro equipment is equipped with an invert feature.

It's only audible in the context of other tracks. If you are playing a single track and invert the phase it sounds exactly the same.
 
Definitely a slight change on my cdp when you invert absolute phase. It's easy to check as there's a little button for that.
 
How can the polarity get swapped in a recording studio?

Every channel on a mixing console has a polarity switch. Then there may be Pin2/Pin3 issues with older gear. And even microphone placement may have issues. For example, where do you put the mics when you close-mic a drum kit? Most engineers will mic the batter head, except for the bass drum which is mic-ed from the resonant head side. So which polarity is right? With a multitrack recording, polarity is likely to be chaos.
 
Every channel on a mixing console has a polarity switch. Then there may be Pin2/Pin3 issues with older gear. And even microphone placement may have issues. For example, where do you put the mics when you close-mic a drum kit? Most engineers will mic the batter head, except for the bass drum which is mic-ed from the resonant head side. So which polarity is right? With a multitrack recording, polarity is likely to be chaos.

And therefore, presumably, if a desk has the facility to sort out this chaos, then it matters that it is sorted out. I can't see the manufacturers of mixing desks adding an unnecessary frippery if it achieves nothing in the overall scheme of things.
 


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