Wall voltage and effects on tone

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MadAsAHatter

MadAsAHatter

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There's been times when all my amps are sounding excellent and other's where none of the settings have changed and things just sound off. A few months ago I got this device that monitors home voltage. I've noticed that it can swing anywhere from as low as 114V to as high as 125V. I know that can affect the voltages in the amp and in turn how the components react. Is this enough to affect tone or am I just hearing things?

What are your experiences? Do you have days where things sound great, touch nothing then it sounds off? Do you use something that regulates voltage going into the amp and have a consistent day-to-day sound?
 
my voltage is usually pretty steady but does vary. I am in the U.K. which is technically a 230v country, typically I see a pretty steady 245v at the wall.

I have a few amps that want 240v and a few that want 230v (based on what the heaters measure at various wall voltages) so I built a bucking transformer with a center tapped 16v transformer so I can switch between (about) -8 volts or -16 volts. I also put a digital meter on it (which I calibrated) so I can accurately monitor wall voltage.

plate voltage can vary a lot depending on wall voltage. One of my amps at 228v at the wall measured 485v at the plate. At 244v at the wall it’s 522v at the plate. I’m not sure how well differences would come though on clips but there is a definite feel difference. Too high voltage is just less fun to play, more plinky and strident. I recall Dave Friedman saying on a livestream once that heater voltage has an affect on tone also, which is why just dropping b+ with a separate HT tap on the power transformer without dropping heaters, doesn’t sound the same as using a variac.

All that being said, sometimes things don’t sound ‘right’ to me even when the voltages are right, and some days everything sounds amazing no matter what, so I’m sure part of it in my own head.
 
I try to only adjust/judge my amps in the morning when my ears are rested but my voltage fluctuates about like the op.
Monitored it all day once and it gets higher in the evenings.
I'll most likely end up with an amprx brown box within a short period. It's not a set and forget fix but at least it does the job without getting into expensive industrial solutions.
 
I run all my amps, computer, effects, etc… on UPS with Automatic Voltage Regulation (AVR). I know it’s not as good as some higher priced units, they are consumer grade UPS’s, but it works.
They display the input and output voltage and keep it pretty steady. It also isolates the gear which helps protect.

For about $100, they’re hard to beat and well with it. Just make sure it has AVR feature.
 
I experience the same thing all the time ...... I think that's why people have those " brown boxes "
 
It can matter quite a bit. In the US a power transformer will take 120v from the wall, and put out 480 or so out of the rectifier, so a 10v difference out of the wall can be significant inside the amp.
That effects the tubes and the bias

Whether it will make your amp sound better or worse is a matter of opinion, but it might put some electrolytics close to their max in some cheaper amps
 
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It can matter quite a bit. In the US a power transformer will take 120v from the wall, and put out 480 or so out of the rectifier, so a 10v difference out of the wall can be significant inside the amp.
That effects the tubes and the bias

Whether it will make your amp sound better or worse is a matter of opinion, but it might put some electrolytics close to their max in some cheaper amps
A residential utility pole primary in the US is about 4000 VAC at which from the pole to your house is a step-down transformer from the 4000VAC to 500VAC [2 legs of 250VAC] for about 90 amps.
Any single AC wall recepticle is 120VAC and about 15 amps.
If your wall voltage is anything more that +/- 2 to 3 volts call an electrician.
Most amplifiers have a +/- tolerance built into the Engineering.
 
A residential utility pole primary in the US is about 4000 VAC at which from the pole to your house is a step-down transformer from the 4000VAC to 500VAC [2 legs of 250VAC] for about 90 amps.
Any single AC wall recepticle is 120VAC and about 15 amps.
If your wall voltage is anything more that +/- 2 to 3 volts call an electrician.
Most amplifiers have a +/- tolerance built into the Engineering.
115 is typical for my area, but a couple towns over where I work 120/121 is more common.
I still have the old screw in fuses in my house and I figure if it ain’t broke don’t fix it.
I’m sure I’ll want more than 100 amp service eventually though lol
 
It 100% fluctuates and 100% affects tone. During the days when its hot and everyone is cranking the A/C, the voltages lower a bit. At night the voltages seem to go up as less people may be using electricity. I've seen my house got as high as 126 volts. I use a brown box and keep my voltages at 114-115 when running my amps. I run both my main head and rack through my brown box. It makes a difference in both sound and feel. It's fun to mess around with voltages as well. I've lowered mine as low as 99 volts. Makes the amps looser and less compressed.
 
The variac is they way to solve the problem bc it is a problem. A loss of a 5vac is exponentially effecting the B+ downstream in the amp. No vac regulator on the market for less than $500 will help. They only begin to work after 10vac and your tone losses at that point are toast unless you are prepared to spend big money on a serious equipment nothing can be done.
 
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Funny to read about this.

Just the other day I was recording some lead parts & was very happy with the tone, so much so that I left my entire rig untouched for a few days to do some more tracking.

Same guitar, not a single knob touched, and suddenly everything sounds noticeably darker & less open. I even went back to the same project in my DAW, duplicated the track I’d been working on, and the night & day difference was still there.

We constantly have issues with the power company anyway, I wonder if I should get something to actually measure that.
 
Sure does. When you get above 122 my amps start to get bright and harsh
 
The variac is they way to solve the problem bc it is a problem. A loss of a 5vac is exponentially effecting the B+ downstream in the amp. No vac regulator on the market for less than $500 will help. They only begin to work after 10vac and your tone losses at that point are toast unless you are prepared to spend big money on a serious equipment nothing can be done.
Using the brown box, at home of course, I simply look at the voltage display to make sure I'm where I want to be. No need for a high dollar voltage regulator.

Years ago I got a big voltage regulator that was used for computer equipment. I plugged it in and it was regulating voltage to around 122v. It was supposed to put out a steady 117v according to the label. It had a few big internal transformers... I think i threw it out. :ROFLMAO:
 
My wall voltage dips down to 108ish regularly (probably have too much on one circuit), and I found it kept making my amps sound dull and bloated.

Wasted time swapping tubes a bunch until I finally invested in a BLA PG-2R which keeps it at a stable 120v and it's been noticeably stable.
 
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