2 TO 3 PRONG POWER CORD MOD ON MY VACUUM TUBE PEDAL......................

Jeffblue

Well-known member
I have a BK Butler Real Tube pedal that is supposedly the precursor to the Tube Driver pedal. The power cord was a 2 prong which means the chassis was ungrounded and introduced noise and someone added an in-line on/off switch. I changed out the power cord and grounded the chassis which eliminated line voltage noise. It is a great sounding pedal.
 
Re: 2 TO 3 PRONG POWER CORD MOD ON MY VACUUM TUBE PEDAL......................

I have tried the Blue Tube version, and I've always liked that.
 
Re: 2 TO 3 PRONG POWER CORD MOD ON MY VACUUM TUBE PEDAL......................

Before the mod, was the chassis connected as a circuit ground?
 
Re: 2 TO 3 PRONG POWER CORD MOD ON MY VACUUM TUBE PEDAL......................

Before the mod, was the chassis connected as a circuit ground?

That's what is so unusual, there wasn't any ground to the chassis at all. I've never seen a BK Butler pedal with a 2 prong plug. I also have a Blue Tube pedal that I did an octal preamp tube mod to and this has a grounded plug.
 
Re: 2 TO 3 PRONG POWER CORD MOD ON MY VACUUM TUBE PEDAL......................

Was the chassis "grounded" through pots, jacks, metal standoffs, anything like that?
 
Re: 2 TO 3 PRONG POWER CORD MOD ON MY VACUUM TUBE PEDAL......................

Was the chassis "grounded" through pots, jacks, metal standoffs, anything like that?

It didn't look like it was and certainly didn't sound like it. It was noisy with 60 cycle hum. Now it is completely silent.
 
Re: 2 TO 3 PRONG POWER CORD MOD ON MY VACUUM TUBE PEDAL......................

That is strange... Typically any pedal enclosure, the circuit contained with in it and the guitar itself ultimately gets its 0 volt reference through the amplifier via the output jacks sleeve terminal of the device, input jack's sleeve of the amplifier, which is usually referenced via the amplifier's chassis and which itself itself typically having an earth reference near where the power cord enters to put it at a 0v potential. unless of course the amplifier itself isn't referenced. It's usually done that way to prevent ground loops between two pieces of equipment. Referencing the pedal enclosure it self isn't a bad idea at all for anything that plugs into the wall, especially for the safety of the user, but ideally you would want an option of a lift between the actual circuit return and the earth referenced chassis in case you do end up with a ground loop
 
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Re: 2 TO 3 PRONG POWER CORD MOD ON MY VACUUM TUBE PEDAL......................

That is strange... Typically any pedal enclosure, the circuit contained with in it and the guitar itself ultimately gets its 0 volt reference through the amplifier via the input jack of the amplifier, and the amplifier's chassis itself typically has an earth reference near where the power cord enters to put it at a 0v potential. unless of course the amplifier itself isn't referenced . It's usually done that way to prevent ground loops between two pieces of equipment. Referencing the pedal enclosure it self isn't a bad idea at all, but ideally you would want an option of a lift between the actual circuit return and the earth referenced chassi in case you do end up with a ground loop

Every other BK Butler that I have ever owned or saw (unless it was one of the units that used a wall wart) all had 3 prong plug/grounded. Never saw one like this before.
 
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