random pedals turn on when i plug in my wall wart

[Seven64]

so i have 2 visual sound 1 spots on my pedalboard with 14 pedals on there.  every time i plug them into the wall, 2 of my pedals turn on.  they are always the same 2 boss pedals, and every once in a while a 3rd turns on.  i am always switching the layout, trying to get my chain right, but no matter which spot on the daisy chain they are on, they do the same thing.

why is this?

[LucifersTrip]

so i have 2 visual sound 1 spots on my pedalboard with 14 pedals on there.  every time i plug them into the wall, 2 of my pedals turn on.  they are always the same 2 boss pedals, and every once in a while a 3rd turns on.  i am always switching the layout, trying to get my chain right, but no matter which spot on the daisy chain they are on, they do the same thing.

why is this?

is there a + ground culprit in there?

[digi2t]

Is there a latching switch at work here?

Are these pedals "on" when you kill the power to them?

Do a test. Ensure that the pedals are "off" when you disconnect the power, then reconnect the power. If the pedal stays off, then it might be the way the switching is set up. If the pedal comes back on again, then there's something else afoot.

I'm intrigued....

[Joe Hart]

This happens to me. I always have my DOD 250 clone on (it has a mechanical 3PDT, so I would expect that to stay on when I power up). But my Danelectro octave always comes on (and it's always off when I turn the power strip off). Also, my BOSS delay comes on and it's always off when I power down. And my BOSS chorus is always on and always comes up off. And my in-line tuner is always on and always comes up off. So, when I power up, I have to click a couple pedals off and a couple pedals on. It's always the same ones, too. Strange. Not a big problem, but I've wondered about it.

I believe the latching switches may have a default setting as on or off depending on the pedal??
-Joe

[CurtisWCole]

Read the technology of boss and ibanez switching on rg's site. www.geofex.com. It has to do with the trannies in the flip flop switch.

Curtis

[R.G.]

Read the technology of boss and ibanez switching on rg's site. www.geofex.com. It has to do with the trannies in the flip flop switch.

And we have a winner.

The Boss and Ibanez switching is nearly identical, and the on or off condition at power up depends on how that internal flipflop comes up. If it were made from perfect and perfectly matched components, the flipflop would come up in a completely random condition, on or off about half the time, as noise would push it to stabilize in one or the other condition.That's for perfect components. With small component differences, the tolerances will slightly bias it to come up one way or the other. It's also possible to pick different component values to make it come up one way or the other.

I believe that your pedals happen to have things 'tilted' a little towards 'pedal on'. This is perhaps a little interactive with exactly how the voltage rises when the power supply is plugged in. Every active power supply is slightly different, again from component and timing differences.

I think this is why it happens. It's not dangerous or an indication that anything is wrong, any more than being left-handed is wrong for a human.

[Mark Hammer]

I suppose we can file this under "proposed/hypothetical virtues of true bypass".  Whatever setting you left that pedal in before powering down, will be its power-on setting next time out...assuming no one has stepped when you weren't looking.

[Paul Marossy]

My Boss DD-5 ALWAYS turns on when I power up the pedalboard. My Ibanez pedals don't however. That's the only Boss pedal on my board these days, I don't remember if my other Boss pedals did that or not though.

[Ice-9]

My Boss PS6 pitch shifter does this, it's not a difficult mod to make sure the 'OFF' state is the one initialised on power up. I haven't bothered before but it would only be making one of the caps or one of the resistors that turn on the transistors in the switching a different value to the 'ON' state side of the flip flop circuit.

[amptramp]

I suppose we can file this under "proposed/hypothetical virtues of true bypass".  Whatever setting you left that pedal in before powering down, will be its power-on setting next time out...assuming no one has stepped when you weren't looking.

The real advantage of electronic switching is that you can add an initialize circuit to make sure the pedal comes up in the state you require.  This may be a separate circuit or just a deviation from mirror image components in the flip-flop circuit that ensures it always comes up in the appropriate state.

[DougH]

It really shouldn't be an issue unless this is your pedal board:

[Paul Marossy]

It really shouldn't be an issue unless this is your pedal board:

HA HA! 

[CurtisWCole]

Read the technology of boss and ibanez switching on rg's site. www.geofex.com. It has to do with the trannies in the flip flop switch.

And we have a winner.

Thanks RG. I'm honored.

Curtis