Originally Posted by stash64
There are two different/valid configurations... European and American. For whatever reason, Emotiva chose to use the less prevalent (now) American pin arrangement.
Here is some info on this somewhat confusing subject- at least for me:
This from QSC audio forum-
There is no "American" or "European" XLR pinout. The AES adopted a standard of pin 2 = + (or "hot") and pin 3 = - (or "cold") back in 1992 (http://www.aes.org/publications/standar ... m?docID=19).
Before that, it was haphazard, with some manufacturers using pin 2 + polarity and others using pin 3 +. It's possible that more European manufacturers used one than the other and more American manufacturers used the opposite (perhaps a point of confusion for Marantz); I only know that there was quite a mix (QSC has always used pin 2 +, but in the early 90s I worked for another US power amp manufacturer that used pin 3 +), and probably the overall number tilted a bit in favor of pin 2. At the September 1990 AES Convention in Los Angeles, the LA section spoofed that lack of decisive coordination by handing out "XLR Polarity Indicator" spinner cards; the possible results were "Pin 2 +," "Pin 3 +," and "Spin again." :lol:
Fortunately, for any processor, cable, or other device with balanced XLR input and XLR output, there is no polarity issue as long as it is the same from in to out. For other audio devices that convert between balanced and unbalanced, such as microphones, power amps, DI boxes, etc., polarity doesn't matter much unless you're using multiple ones (i.e., more than one amp) with different polarities.
Technical Communications Developer
Fellow, Audio Engineering Society
This from the Stereophile XPA review-
"The gain at the loudspeaker terminals for both balanced and unbalanced inputs was 29.4dB, and while the output preserved absolute polarity (ie, was non-inverting) for the unbalanced input, the balanced input inverted polarity, suggesting that the XLR jacks are wired with pin 2 cold, the opposite of the modern convention.
The balanced input impedance was moderately high, at 27.5k ohms; the unbalanced input impedance was 14.5k ohms at low and middle frequencies, dropping to 9.5k ohms at the top of the audioband.
Read more at https://www.stereophile.com/content/emotiva-xpa-gen3-two-channel-power-amplifier-measurements#c7HcpV5P3khGWqp8.99"
So from what I can figure this would cause phase problems if:
-you mixed balanced (XLR) and unbalanced (RCA) connections coming into the XPA, or
-you were using another model amp for some channels along with the XPA
Since I am using just the XPA for my speakers I figured it I was cool, UNTIL I remembered I did have a different amp in my HT setup-- my SVS sub's built in amp.
So I checked its manual and couldn't find anything there re: pin configuration.
So I decided to use the 'null' method to check the phase between my sub and my fronts at the x-over frequency. I changed the subs phase setting from 0*, 15* at a time and noted the SPL reading at each phase level up to 180*. At 180* I had the highest level, at 0* the lowest SPL reading.
The point of this post is if you are using the XLR connections into the XPA and have a powered sub connected to your processor you would be wise to check your speaker/sub phase. It doesn't take very long to do. Dirac, AFAIK
, does not adjust for phase between subs and mains, but would would be happy to be corrected if I'm wrong.