Wall outlets reading 125.6 volts

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Fret-Shredder

Fret-Shredder

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Hey guys.... I decided to check my wall outlets throughout my house and the average reading I'm getting on my Fluke multimeter is 125.6 volts AC. Do you think it's a bit high? Could it potentially do any damage to my amps and even rack gear? Just wanted to hear your thought on this. Thanks in advance.
 
That’s high to me. I’d get something to get it down to 120 which is what most electronics want to see nowadays. I run a good quality power strip into a Staco variac. I don’t know about “damage” but that voltage is enough to throw your bias off which can affect tone/tubes.
 
Fret-Shredder said:
Hey guys.... I decided to check my wall outlets throughout my house and the average reading I'm getting on my Fluke multimeter is 125.6 volts AC. Do you think it's a bit high? Could it potentially do any damage to my amps and even rack gear? Just wanted to hear your thought on this. Thanks in advance.
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The rack heat likely has regulators. As for tube amps unless you have a really high plate voltage to begin with, you should be fine. If your B+ is higher as a result, you bias supply will be hotter as well, likely keeping things is check bias wise.
 
It is actually normal for the line voltage to fluctuate throughout the day depending on the load demands from the grid.

My AC voltage can read as low as 110-115 during high summer loads and can read as high a 125 ACV when the grid load is low. I run a Furman AR 1215 voltage rack regulator to clamp my ACV to a regulated amount range.

As scottosan states if your amps are biased at say 118-120 AC volts when the amp is run at 125 ACV your amps plate voltage9B+) will be higher inducing your bias supply to be hotter causing more current draw through your tubes wearing them a slightly greater rate depending on how hot your bias was set when the amp was at 110-120 AC volts.

As long as the amp bias was not set super hot say 70% dissipation then it's usually not a huge deal. If the amp was set to 50-60% then the bias drift would be manageable and not a big deal.
 
Best $50 you'll spend in the link below.

I use a Variac to keep voltage consistent so my amps sound the same from day to day. Secondly, it keeps things consistent when adjusting preamp voltages, bias etc....

I tend to use 117 VAC as a baseline. I'll run my 69' Super lead at 90-100 VAC, which is fun. Just a lot of flexibility for the money.

https://www.circuitspecialists.com/...ztvoiUqrf8bw6L6kDrIGyKEgMsmdBiE4aAumwEALw_wcB
 
RedPlated said:
Best $50 you'll spend in the link below.

I use a Variac to keep voltage consistent so my amps sound the same from day to day. Secondly, it keeps things consistent when adjusting preamp voltages, bias etc....

I tend to use 117 VAC as a baseline. I'll run my 69' Super lead at 90-100 VAC, which is fun. Just a lot of flexibility for the money.

https://www.circuitspecialists.com/...ztvoiUqrf8bw6L6kDrIGyKEgMsmdBiE4aAumwEALw_wcB
Click to expand...

Interested at that price point. Juice Goose in my rack reads 125 at my place. I have been looking at the Brown Box or Furman stuff but those are much more expensive.
 
Brown box can’t be dialed in to exact voltages, either, as far as I remember.

Dave Friedman uses the one in the link above. He recommended it to me. It’s on his work bench, you’ll likely see it in YouTube videos.
 
Fret-Shredder said:
Hey guys.... I decided to check my wall outlets throughout my house and the average reading I'm getting on my Fluke multimeter is 125.6 volts AC. Do you think it's a bit high? Could it potentially do any damage to my amps and even rack gear? Just wanted to hear your thought on this. Thanks in advance.
Click to expand...
Sometimes you can get the power company to come out and check their transformer if your wall voltage is too hot. They did it for me when I lived in San Diego and were able to lower my wall voltage along with my neighbors who were getting power from the same transformer.
 
And be sure your Variac is reading accurately. The wall voltage in my guitar/amp room was reading 123 VAC pretty reliably. But my Variac, when set to 120 or 100 or whatever, was not reading that on my DMM. I loosened up the big knob on my Variac and re-indexed it to give an accurate reading. Though I almost never use it.
 
Correct me if I am wrong but I think the limit of what the electric co. should be giving you is 128V.

If you check your voltage every few hours for a couple days and it goes even higher, you can petition the electric company to put a step down resister at the pole.
 
RedPlated said:
Brown box can’t be dialed in to exact voltages, either, as far as I remember.

Dave Friedman uses the one in the link above. He recommended it to me. It’s on his work bench, you’ll likely see it in YouTube videos.
Click to expand...
There are certain setting that wont allow for singular voltage changes... but for me its versatile enough down to 105 volts. I'm not looking for go any lower. The cheaper easier route is to buy the variac listed above. One of my biggest fears was that my wife or kids would turn the variac knob and poof. Thats not happening on the brown box.
 
psychodave said:
There are certain setting that wont allow for singular voltage changes... but for me its versatile enough down to 105 volts. I'm not looking for go any lower. The cheaper easier route is to buy the variac listed above. One of my biggest fears was that my wife or kids would turn the variac knob and poof. Thats not happening on the brown box.
Click to expand...
Always set and tape the knob down on my variac.
 
RedPlated said:
Best $50 you'll spend in the link below.

I use a Variac to keep voltage consistent so my amps sound the same from day to day. Secondly, it keeps things consistent when adjusting preamp voltages, bias etc....

I tend to use 117 VAC as a baseline. I'll run my 69' Super lead at 90-100 VAC, which is fun. Just a lot of flexibility for the money.

https://www.circuitspecialists.com/...ztvoiUqrf8bw6L6kDrIGyKEgMsmdBiE4aAumwEALw_wcB
Click to expand...
Wow, it’s one of those cheap eBay Chiners with an accurate LCD? Nice. That’s a deal!
 
RedPlated said:
Brown box can’t be dialed in to exact voltages, either, as far as I remember.

Dave Friedman uses the one in the link above. He recommended it to me. It’s on his work bench, you’ll likely see it in YouTube videos.
Click to expand...

That may have just clinched it for me. Guess I am going to go shopping today. At that price, it is worth the experimenting.
 
I work in the electrical industry and your local power company is allowed +/- 15% on the power. Get a good power conditioner or even better get a good power supply/regulator that will give you constant power no matter what your incoming house power is reading. A variac doesn't offer you this level of protection. There is a good video online where the AC/DC guitar tech is explaining Angus Young's rig and talks extensively about the power units that they use to insure a constant power source and they can bump up or bump down to make more vintage amps run/sound better like a variac.
 
That video with Angus Young's tech has some pretty cool toys. But that Japanese industrial-grade Variac rig they use is big money. IIRC, it was around $14k.
 
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