Φ--- faceplate symbol for polarity?

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boji

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Jan 6, 2010
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I've heard a few people correct those who say phase when they mean polarity.  Might someone care to shed some light on the distinction when coming off a transformer?

I like the 'Phi' symbol. Nice and stout, and would look good for polarity flip button.  ;D
 
Back when I used to rack console modules:

http://www.brianroth.com/custom/custom.html

...I wrestled in my mind with that label, and decided to use POL REV as the legend.  But, occupies a lot more panel space.

Bri

 
boji said:
I've heard a few people correct those who say phase when they mean polarity.  Might someone care to shed some light on the distinction when coming off a transformer?

I like the 'Phi' symbol. Nice and stout, and would look good for polarity flip button.  ;D
We've had this discussion here before too...  ::)

Phi is cute and fits on tight faceplates, but might not be understood by everybody (important IMO).  :-[

Phase is well understood but not accurate, so irritates people like me.  :mad:

Polarity is hard to fit in, but correct.  8)

JR
 
Phase by itself is ambiguous.  How many degrees of phase shift and at what frequency? Polarity is well defined,  a reversal of + / -, reversal of hot / cold,  180 degree shift at all frequencies.

For labeling phase,  polarity,  pol,  phi are all common.  Use what you like.
 
john12ax7 said:
Phase by itself is ambiguous.  How many degrees of phase shift and at what frequency? Polarity is well defined,  a reversal of + / -, reversal of hot / cold,  180 degree shift at all frequencies.

For labeling phase,  polarity,  pol,  phi are all common.  Use what you like.

I don't think phase is particularly ambiguous in this context, since it is assumed to be 180degrees of phase shift across the entire audio band, unless there is a Mic pre phase/polarity switch that intentionally doesn't do that.  ;D
 
iampoor1 said:
I don't think phase is particularly ambiguous in this context, since it is assumed to be 180degrees of phase shift across the entire audio band, unless there is a Mic pre phase/polarity switch that intentionally doesn't do that.  ;D
Back last century I labelled the switch "phase" because polarity didn't fit in the panel space I had available, while in the owner's manual copy I described the switch function properly as "reversing absolute polarity" . 

IMO the larger sin is not being easily understood, even by casual users. Phi is cute, but if you have to explain what it means, you failed at labelling the controls. Phase despite being inaccurate is likely to be interpreted correctly by operators looking to change that signal relationship. 

JR
 
How polarizing a topic.  /honk

I just wanted a bit of chiding to get my right brain to let go of this one.

POL it is.

Nice rackups Mr. Roth!

Confusion for the newb might invite experimentation. Or fear paralysis.  ???
 
boji said:
How polarizing a topic.  /honk

I just wanted a bit of chiding to get my right brain to let go of this one.

POL it is.

Nice rackups Mr. Roth!

Confusion for the newb might invite experimentation. Or fear paralysis.  ???

Thanks!

Those projects were from a long time ago before a bunch of other folks began hanging modules from a piece of angle iron with  XLR's dangling from the back side, for far less money.  I just shrugged and moved on because  I refuse to deal with junk projects and fight with "so and so will rack this for $4.95 and can you match that price?"

I grew up in another time when pro audio equipment was built to a higher standard.  Quoting Tom Petty "I won't back down and I'll Stand  My Ground"  <g>

Glad to be semi-retired from much of the BS! 

Back to my choice of legends....switch flipped UP engaged that function, just as the overhead light in the kitchen went ON in the Up position.

Bri


 
The question is, why would someone want to change the phase to something different  than 180 degrees?
 
weiss said:
The question is, why would someone want to change the phase to something different  than 180 degrees?

For one example in loudspeaker crossovers the "phase" response of 3 pole filter alignments do not create a dip or null at crossover point, like older 2 pole alignments did. Those old 2 pole crossovers required a polarity switch on one output so you could flip one output opposite polarity to prevent the 180' (degree) out of phase suck out at the crossover point (confused yet?). The modern 4 pole crossover alignment that is now popular rotates that phase a full 360' (degrees) so back in phase again (at least for persistent sine waves).
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Other popular studio/guitar effects like Phasors intentionally create a comb filter using phase shift.
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I believe one studio product manufacturer included an adjustable phase (yes phase) knob on his preamp so the user could presumably reduce comb filtering from two mics on a drum kit picking up the same signal with different path delay, or whatever... I prefer setting the mics up properly (or using less mics).  ::)

JR
 
We could just go 'all in':

kGmjobv.jpg
 
With the luxury of that much panel real estate, and for your own use, label it whatever you want.  :p

I typically had 4 switches in that immediate area (pad, polarity, phantom, mic/line) and less space available.  Plus I had to be easily understood by paying customers, and their customers.

The greek alphabet existed back then, and even "pol" is not immediately grasped as short for polarity by all. Most experienced operators could figure out even an unlabelled button from proximity and context where it is located.  8)

Some exotic brands might even prefer the obscure phi nomenclature.

JR
 
JohnRoberts said:
Back last century I labelled the switch "phase" because polarity didn't fit in the panel space I had available, while in the owner's manual copy I described the switch function properly as "reversing absolute polarity" . 


JR
Oh how about a rap button?
 

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