Wall Voltage Follies

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kinmike
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Wall Voltage Follies

Post by kinmike »

Wow,

My wall voltage is usually 123VAC and I’ve posted about using a dropping resistor to get the B+ into the sweet spot using a clone PT. Well this week, with time off, I’ve been working on a new build. The wall voltage has been 117 VAC for three days straight! WTF?

Nothing new around here power wise that I can tell.

Mike
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AussieTim
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Re: Wall Voltage Follies

Post by AussieTim »

I am wondering if you can hear any difference wen playing the amp? I have always blamed my bad playing for sonic differences, now I might have to whip out the multimeter and blame the voltage.
Just thinking how many great rock and roll were recorded in the 50s 60s and 70s when supply voltages were far from constant and ponder how much this affected the sound and whether all the hyperbole of using vintage and vintage recreation components is misplaced when all that is needed is an unstable power supply.
Serious question how much variation in B+ voltage are you getting with the 6 ACV variation in supply voltage, where I live we can have up to 15 ACV variation on a supposed 230 ACV supply.
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kinmike
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Re: Wall Voltage Follies

Post by kinmike »

AussieTim,

That's a good question but one I'm not sure I can answer objectively. There are times when amps sound better than other times but I've never stopped and whipped out the voltage meter to check.

However, the consensus around here is that the 18 Watter B+ voltage has a sweet spot at 340vac. Myself and others have jumped through hoops with zeners and dropping resistors to achieve it because the consensus is coming from some pretty knowledgeable and experienced people. I also agree that it sounds pretty good at 340 and less so at 360.

I know my wall voltage will go back to 123 and the majority of places I will play the amp will be there or above, putting my B+ at 360 or more without dropping it.

Mike
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JMPGuitars
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Re: Wall Voltage Follies

Post by JMPGuitars »

*340VDC

But anything in the 340s is usually good.
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crgfrench
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Re: Wall Voltage Follies

Post by crgfrench »

My wall voltage fluctuates and I dont know much about that but I know for sure that my amp sounds better after about 4 Guinesses.
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kinmike
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Re: Wall Voltage Follies

Post by kinmike »

crgfrench wrote:
Wed 01/01/20 6:27 pm
My wall voltage fluctuates and I dont know much about that but I know for sure that my amp sounds better after about 4 Guinesses.
Definitely a law of physics right up there with Ohm's...
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