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Speaker phase observation and question?

Hi everyone,

After months of playing around with positive phase and reverse phase connections to my Monitor Audio Silver 8 speakers, I have made a couple of observations. When connected in positive phase (red - red, black - black), the speakers put out pretty substantial bass, but the mids and treble are somewhat subdued. Upon reversing the phase, the mids and treble open up substantially, and the bass becomes somewhat subdued. To my ears, I actually prefer the reversed phased.

Moving forward to the current day, I purchased an app that tests phase using a generated tone. In testing my speakers, both bass drivers test positive phase, but the mid and treble test negative. I had read somewhere that some manufactures wire the drivers like this intentionally, but am confused as to whether or not this is the case with my speakers, or if it's a manufacturing flaw?

Any thoughts? 
chewie70
kosst_amojan
2,095 posts
 
@erik_squires My Focal 936's are exactly opposite of what you suggest about woofer polarity. The midrange and tweeter are in positive polarity while all 3 woofers operate in negative. 

The point of my comment was to point out how speakers are reactive and not subject to the superficial presumption that when voltage is applied a driver reacts predictably. A lot of people don't consider that a driver and crossover become more or less capacitive or inductive when driven by a signal and that the current draw that actually drives the speaker can be significantly ahead of or behind the voltage. 
erik_squires
5,268 posts
 
Hi @kosst_amojan,

Well that is unusual, but not the end of the world.

Well, I consider that quite predictable, this is what math and simulations are for.

But your comments seemed to be mixing up phase and polarity.

Best,

E
kalali's avatar
kalali
1,645 posts
 
Polarity is absolute; + or -, phase angle varies as a function of the frequency. Completely different concepts.
shadorne's avatar
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shadorne
7,333 posts
 
Polarity should not make that much difference. Unless you go one speaker reversed polarity and the other normal. 

That said - you are deaf in one ear.  In those with full hearing the brain does a lot of processing using BOTH ears - perhaps you are experiencing more masking from bass frequencies in one polarity vs the other because you only hear with one ear.
timlub
1,649 posts
 
Hi Guys,  most of you know that I've been building speakers for 35 + years... Overall this is a great thread..
I noticed a couple of comments of phase angles.. Kalali mentioned that they are very different.
Phase angles show us how current rides with the voltage within the speaker... if current rides in front of or behind the voltage, you will see the large rises or dips in phase angles. So the phase angle changes how a speaker sees power...
Phase/polarity is important in the sense of keeping your individual drivers moving in unison... when a speaker is 180 degrees out of phase,  one driver has complete excursion moving outward and another driver has complete excursion moving inward. 
In theory when designing a crossover,  6db per octave gives you 90 degrees out of phase, 12db produces 180 degrees out of phase, 18db per octave produces 270 degrees out of phase and 24db per octave produces 360 degrees or full circle back in phase.
The most used crossover (which I don't use at all) is 12/12 slopes,  that means that the slopes between 2 drivers is 12db up from the woofer or mid to the tweeter and 12db down from the tweeter... Again, in theory, this is 180 degrees out of phase.  A designer can simply switch polarity and bring phase/polarity back into alignment.  A ton of things go into a design so that basic theory is not absolute,  but this is an accurate look at the theory behind speaker phase/polarity. 
I hope this little explanation helps, 
Tim
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