Polarity Switch

[mike_sims]

I'm wondering about the Polarity switch on my Model T's. I noticed one model T has the switch flipped the opposite of the other, but I'm not noticing much. I think there might be a little "hum" or "buzz" going on, but that can also be from my P90 pickups... what exactly does flipping the switch do? (obviously it reverses the polarity) I'd like a more in depth analysis. Thanks.

[bigobassman]

I'm no expert, but those polarity switches were on there prior to the grounded 3 hole wall electrical outlets were being used.  Sometimes, you could take the plug itself and turn it around and that would help the "noise" issue in addition to flipping the polarity switch.  Most agree that those 2 prong cords should be replaced with the 3 prong ones.  Much,much safer.  My hair's curly from getting shocked so much in the 60s.     Keep the original cord for posterity and remember the polarity switch will no longer be functional.   

[Isaac]

But the Model T came with a 3 prong plug *and* a polarity switch.

[mike_sims]

But the Model T came with a 3 prong plug *and* a polarity switch.

haha yeah... Kinda funny, what to do then?

[bigobassman]

But the Model T came with a 3 prong plug *and* a polarity switch.

As noted, no expert, particularly having never seen a Model T in person.  That's one of those deals that make you go    Good luck with your problem Mike.   As you noted, hums noises etc. can be a bit tricky finding the source or sources.  Some of the older SS stuff has some that you just have to EQ out.  In fact, I just today learned that the older Peavey Black Widows with the aluminum dome can be a source of a high pitched hum.  Something about the cap being more than just a voice coil cover.  There is more to it that is apparently good for certain applications, particularly steel guitar.  Sorry I don't remember the details.  But, it's an annoying hum for bass guitar.   

[matto)))]

But the Model T came with a 3 prong plug *and* a polarity switch.

The polarity switch, normally not needed on a three prong grounded power supply, is here in recognition of the fact that "some venues may not have updated house wiring".

[mike_sims]

hmmm well, my other Model T has the polarity switched flipped the opposite of this one and isn't humming.. So I'm wondering if I flip the switch on this one if the Hum will cancel. I just don't want to get shocked... Can you get shocked from flipping that polarity switch? I'm assuming not since it hasn't happened to me with my other one.

[stanner]

all my Ts have that switch going either way w/ no discernable hum from any of them. i also use p90s and while they do emitt a slight hum of sorts - its not to my dislike. ymmv

[mike_sims]

well i think it's not grounded properly. tried it side by side with my 2nd gen and the 2nd gen isn't buzzing. the genius who last serviced it screwed the screws in crooked so now it's real fun to take out of the case, i'm assuming the professor didn't even fix the ground connection that was stated on the paperwork. looks like i'll be having it serviced.

[stanner]

ya do wot ya gotta do(good luck!! my friend!!)

[gtrplayr1976]

Bypass the polarity switch, install plug with ground, disconnect death cap.   

[mike_sims]

the plug is grounded.... i opened it up and saw the connecton was good, possibly a bad tube.