50 Watt Tube Amp Current Draw:

Inspector #20

Inspector #20

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I was reading about a device called the Morley Hum Exterminator that fters the AC Mains Ground of transient voltages.

It said it works on any 115VAC device that draws less than 6 amps.

Just curious to know what a 50 watt tube Marshall, a 100 watt solid state Blackstar, (2) One Spots powering (11) FX would be drawing from my single Fuhrman SS-6B power strip???

Also, is this a good device to use considering the inconsistent wiring at many older venues???



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If your issue truly is a ground loop, which appears to be the case based on the fact that your noise goes away when you unplug the guitar cable from one of your amplifiers, plugging your power strip into the the Morley Hum Exterminator will likely not correct the issue. Instead, you’ll need to pick one amplifier, plug that amp into the Hum Exterminator, plug the Exterminator into the power strip, plug the rest of your devices and other amp directly into the power strip, then plug the strip into the wall. This is because the actual ground loop is occurring within the strip, as that is the place where the actual earth ground is shared by the devices. Putting the Exterminator after the strip won’t interrupt that loop.

That said, I am a bit leery of these devices. They typically work by placing diodes and a resistor on the ground line. Thus, there isn’t a straight, plain-wire connection to ground. The idea is that, in a shorting situation, the diodes will allow enough current through on the ground connection to trip a breaker or blow a fuse, cutting off power to the device. They also assume a dangerously high over-current condition will short the diodes, which is normally how semiconductors fail, but they may fail to an open, as well. Have you noticed how the Hum Exterminator doesn’t have an Underwriters Laboratory (UL) listing printed on it? Use with caution.
 
smitty_p said:
If your issue truly is a ground loop, which appears to be the case based on the fact that your noise goes away when you unplug the guitar cable from one of your amplifiers, plugging your power strip into the the Morley Hum Exterminator will likely not correct the issue. Instead, you’ll need to pick one amplifier, plug that amp into the Hum Exterminator, plug the Exterminator into the power strip, plug the rest of your devices and other amp directly into the power strip, then plug the strip into the wall. This is because the actual ground loop is occurring within the strip, as that is the place where the actual earth ground is shared by the devices. Putting the Exterminator after the strip won’t interrupt that loop.

That said, I am a bit leery of these devices. They typically work by placing diodes and a resistor on the ground line. Thus, there isn’t a straight, plain-wire connection to ground. The idea is that, in a shorting situation, the diodes will allow enough current through on the ground connection to trip a breaker or blow a fuse, cutting off power to the device. They also assume a dangerously high over-current condition will short the diodes, which is normally how semiconductors fail, but they may fail to an open, as well. Have you noticed how the Hum Exterminator doesn’t have an Underwriters Laboratory (UL) listing printed on it? Use with caution.
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Good points.

I'm really starting to look deeper into these things, because as my board has grown, so have my electronic anomalies.

Please see my post in 'Stomping Grounds' about power conditioners. I'd appreciate your input.
 
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Robert Herndon said:
Just curious to know what a 50 watt tube Marshall, a 100 watt solid state Blackstar, (2) One Spots powering (11) FX would be
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I'm a gadget goon! This is one of the greatest gadgets known to syscokid: My P3 Kill-A-Watt EZ! It's got all kinds of measuring features, but the most important ones for me are AC at the wall socket, total current drawn, and watts consumption.
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P3 P4460 Kill-A-Watt(Tm) Ez
 
syscokid said:
I'm a gadget goon! This is one of the greatest gadgets known to syscokid: My P3 Kill-A-Watt EZ! It's got all kinds of measuring features, but the most important ones for me are AC at the wall socket, total current drawn, and watts consumption.
View attachment 75895

P3 P4460 Kill-A-Watt(Tm) Ez
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I’ve had a Kill-a-Watt for years. I put a lot of devices (vampires) on switches after measuring them. I have a toaster oven that sucks 3 watts just sitting there 23.9 hours a day doing nothing. Same with 2 coffee pots and a microwave, all on outlet mounted switches.

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Robert Herndon said:
I was reading about a device called the Morley Hum Exterminator that fters the AC Mains Ground of transient voltages.

It said it works on any 115VAC device that draws less than 6 amps.

Just curious to know what a 50 watt tube Marshall, a 100 watt solid state Blackstar, (2) One Spots powering (11) FX would be drawing from my single Fuhrman SS-6B power strip???

Also, is this a good device to use considering the inconsistent wiring at many older venues???



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The short answer is that there should be a sticker on the amp that states its power consumption. Take that value, divide it by whatever voltage you think you might have out the socket and you'll be in the ball park.

The Marshall will probably be rayed at around 140 watts, the Blackstar is trickier. If it is indeed 100 watts RMS it should be rated at around 130. I fit is so called "SS watts" it's probably rated at around 60.
 
Robert Herndon said:
I was reading about a device called the Morley Hum Exterminator that fters the AC Mains Ground of transient voltages.

It said it works on any 115VAC device that draws less than 6 amps.

Just curious to know what a 50 watt tube Marshall, a 100 watt solid state Blackstar, (2) One Spots powering (11) FX would be drawing from my single Fuhrman SS-6B power strip???

Also, is this a good device to use considering the inconsistent wiring at many older venues???



View attachment 75874
Click to expand...

It will filter many types of noise from the AC line. How well it works depends on the type of noise.
Power Harmonics it probably doesn't work. Harmonics can be a major headache and a nightmare. Back EMF from large motors can blow the poop out of everything.
It will suppress quick voltage spikes....
But it doesn't turn bad power into good power.

There is power regulators and re-generation which is more like turning bad power into good power....
and it has the price tag to match.
Power can be so bad sometimes (rarely) that there is no other choice but to re-generate the power.
 
Robert Herndon said:
Good points.

I'm really starting to look deeper into these things, because as my board has grown, so have my electronic anomalies.

Please see my post in 'Stomping Grounds' about power conditioners. I'd appreciate your input.
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You are over 6 amps, if you consider the maximum (full loudness of amp)

3 amp 50 watt head
5 amp 100 W head
FX Power supply unknown
Max is more than 8 amps already.
Should be using 15 amp / 20 amp service if you want to consider maximum of 8+ amps..
 
Don O said:
I’ve had a Kill-a-Watt for years. I put a lot of devices (vampires) on switches after measuring them. I have a toaster oven that sucks 3 watts just sitting there 23.9 hours a day doing nothing. Same with 2 coffee pots and a microwave, all on outlet mounted switches.

View attachment 75897
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Would these have a musical application???
 
Robert Herndon said:
Would these have a musical application???
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No, but it lets you measure how much power (in watts) a device is using. You'd be surprised how many things around the house are sucking power doing nothing (AKA vampires). For instance, my toaster over at (3W*24hr*365days)/1000= 26.28 kwh. At 24 cents per kwh (SCE) is $6.30 per year. Doesn't seem like much but add a bunch of other devices and the switches pay for them selves in the first year.
 
Don O said:
No, but it lets you measure how much power (in watts) a device is using. You'd be surprised how many things around the house are sucking power doing nothing (AKA vampires). For instance, my toaster over at (3W*24hr*365days)/1000= 26.28 kwh. At 24 cents per kwh (SCE) is $6.30 per year. Doesn't seem like much but add a bunch of other devices and the switches pay for them selves in the first year.
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Very cool!!!!
 
As a rule of thumb a 50W tube or hybrid amp should draw something around 160-200W. Dependent on the number of tubes and the heating demands of the power tubes - 6L6GC need only 2/3 of EL34.

Devide this by the real voltage.

With a transistor amp You just save the heater currents.
 
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Don O said:
I put my Spectrum cable box, at 25w idle, on a home automation timer switch so the it powers off at midnight and doesn’t turn on until 5 PM. It also Alexa controlled so I can always have her turn it on before 5 if needed. Saves $38/yr.
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Wow!
 
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