50Hz vs 60Hz cycles - tonal impact?

[Bombacaototal]

I am on a rabbit hole recently. I own a '65 Fender Bandmaster, blackface. It was built to operate at 117V, 60Hz. I am based in the UK, with 240V mains and 50Hz cycles. My step down transformer gets my voltage down to 120V but does not change the cycles. I had ordered a Brown Box some time back to get the voltage down to 117V but the unit came defective as it was overheating to the point I could not touch it, and I have returned it since. I have been increasingly curious if the 50Hz to 60Hz will have tonal impacts on my Bandmaster. The solution would potentially be to buy a programmable AC supply, that I could set to 117V and convert the cycles to 60Hz, but these are super expensive. Alternative would be to order a new Brown Box, to make sure at least I am at 117V (step down transformer to 120V then Brown Box to 117V), but that option does not account for cycles. I did notice substantial sound difference between 120V and 117V operation.

Any tips?

[martin manning]

The easiest and cheapest solution would be to set up a bucking transformer to drop the 120V down to 117. This could be done using a 6.3V filament transformer rated for say 3A. The 50Hz vs. 60Hz makes the amp's power transformer operate closer to saturation, i.e. makes the core looks small. If it does not run too hot, your should be fine.

[bepone]

in short, there is no any difference between 117-120V and 50Hz/60 Hz, maybe would be at 400Hz or 1000Hz supply networks but this doesnt exist

[bepone]

... I had ordered a Brown Box some time back to get the voltage down to 117V ..
..
Alternative would be to order a new Brown Box, to make sure at least I am at 117V (step down transformer to 120V then Brown Box to 117V),
Any tips?

brown box?
where is a problem to order 400VA transformer from 230-240V (selectable, or only 240V) to 117V? you can paint it brown after if you want...

[Bombacaototal]

The easiest and cheapest solution would be to set up a bucking transformer to drop the 120V down to 117. This could be done using a 6.3V filament transformer rated for say 3A. The 50Hz vs. 60Hz makes the amp's power transformer operate closer to saturation, i.e. makes the core looks small. If it does not run too hot, your should be fine.

Thanks for the suggestion Martin. I have been trying to find a 50Hz to 60Hz converter with no avail. I find the amp sounds very different between 117V and 120V, specially in the top end, I wonder if the cycles will have an audible effect too

[sluckey]

If the power supply is properly filtered, I would think there should be no difference between 50 or 60Hz, or even 400Hz. Well except, 400Hz would require much smaller filter caps.

[R.G.]

If you think you can hear a difference in tone between 117Vac and 120Vac, you certainly do hear it. Other people may or may not be able to hear it, though.

If you think you can hear a difference in tone between 117Vac and 120Vac, you may be blessed and cursed with incredibly fine tonal perception. The blessed and cursed is the same thing. We commonly have variations of more than 3Vac in our mains power voltage at different times of day. Unless you can actively regulate the voltage, you're going to get changes unless the UK is much better at keeping it constant than we are in my part of the USA.

Brown boxes, bucking transformers, and so on do not actively regulate the voltage, they merely subtract a few volts from what comes in. If what comes in varies, so will the output of these kinds of devices.

There is a technical basis for a tonal difference between 50hz and 60hz. The ripple voltage after your rectifiers will be 100Hz or 120Hz depending on which you have. If your amp has places that let the ripple voltage into the circuit, then the residual ripple will react differently with the circuit, and there may be a slight difference in the resulting tone. Although the previous answers are correct - there won't be much if any of this audible as long as the power supply filter caps are doing their job well. How new are your filter capacitors?

You are correct that changing 50hz to 60hz is difficult and therefore likely to be expensive and unusual. Real lab-grade devices are hugely expensive. It might be possible to do something with an un-interruptible power supply that works from batteries to make 60Hz, but that beings in its own set of tonal issues to one who is ultra sensitive to this.

[neskor]

If the Power transformer is well built then shouln't be any problem, but if its conservatively designed it can be a problem with buzz,heat and voltage drop.
Transformers rated at 60Hz should not be used on a 50Hz supply due to higher losses and core saturation, and the resultant higher temperature rise.
Transformers rated for 50Hz, however, can be operated on a 60Hz supply.
If a 60Hz transformer is to be operated on 50Hz, its applied voltage must also be reduced by 1/6 or the peak flux in the core will be too high. This reduction in applied voltage with frequency is known as derating.
Similarly, a 50Hz transformer may be operated at a 20% higher voltage on 60Hz if this action does not cause insulation problems.

[Stevem]

Here’s some info that should be of interest to you.

I have my 1967 here opened up to replace the Trem roach so I did some test.

My veriac that can go above wall voltage I have lent out right now, so I had to use my other one that tops out at 100%

With 115 vac coming in I have 417 volts on the output tubes which are idling at .038 amp.
A 800 hz sign wave input will allow the amp to output 46.9 watts RMS into a 4 ohm resistive load at the start of clipping.

Backing down my wall voltage to 112 the amp now has 402 volts on the output tubes and there are idling at .036 amp.

RMS wattage at clipping is 40.3.

For you on 50hz which is a 17% slower filter recharge rate I think you will hear way more of a difference starting at the point where your amp clips if you play it that loud then what you might head by running it on a tad lower ac input voltage.

Bottom line, I am not sure how your twice as large wall voltage yet 50 hz impacts your amps performance.

Here’s another interesting story I can relay.

Where I work we make audio recording gear.

We introduced a new product that was selling in Japan that was powered off of a 12 vac wall wart that fed a regulator.

Japan runs on 50 hz, but anywhere from 110 to 100 vac out of the wall.

Even with only 110 and 50 hz the gear would perform fine, but at 100 it could not even idle, and this issue was compounded by the 50 hz .
Now this gear is a compressor and is SS so it does not need much current.

Luck for us the LM317 regulator we use in it can accept up to 36 vdc of input so the only thing we had to change was to now use a 24 volt wall wart and then the unit still worked normal even on only 100 volts.

[Bombacaototal]

We commonly have variations of more than 3Vac in our mains power voltage at different times of day. Unless you can actively regulate the voltage, you're going to get changes unless the UK is much better at keeping it constant than we are in my part of the USA.
to this.

You are correct, in the UK the voltages fluctuate fairly substantially, specially depending on how cold/hot wet/dry the weather is. In my current place I have anywhere between 245V and 234V (but I have been to other sites with vintage at 254V plus). I use an Eurovolt, which is essentially the European brown box. This unit is usually left out of sight, but every time I hear my amp not sounding like I'm used to, I go check it and usually the voltage is down by 3V or more. This is only when I am playing in my own in front of the amp, but enough to bother me tremendously. Worth adding the caveat that in a full mix and amp with mics feeding a headphone I cannot really tell, or if there are more instruments in the same space.

Brown boxes, bucking transformers, and so on do not actively regulate the voltage, they merely subtract a few volts from what comes in. If what comes in varies, so will the output of these kinds of devices.

That is true! I wish AC programmable supplies were not so expensive, but this bothers me so much that I am at tipping point to trying one out

There is a technical basis for a tonal difference between 50hz and 60hz. The ripple voltage after your rectifiers will be 100Hz or 120Hz depending on which you have. If your amp has places that let the ripple voltage into the circuit, then the residual ripple will react differently with the circuit, and there may be a slight difference in the resulting tone. Although the previous answers are correct - there won't be much if any of this audible as long as the power supply filter caps are doing their job well. How new are your filter capacitors?

On the Bandmaster I recapped that amp a few months back. They should be fairly new in that sense

You are correct that changing 50hz to 60hz is difficult and therefore likely to be expensive and unusual. Real lab-grade devices are hugely expensive. It might be possible to do something with an un-interruptible power supply that works from batteries to make 60Hz, but that beings in its own set of tonal issues to one who is ultra sensitive to this.

Thanks for the input as usual!

[Bombacaototal]

Thank you very much for the note Neskor and Stevem. Really helpful

[CraigGa]

On a connected note, I also have a Line6 Helix and that models amp hum at 60hz and it just sounds wrong to a 50 hz'er like me.

Craig

[LOUDthud]

Just curious, what do you do if you are on tour with a Hammond Organ ? I think you have to use a UPS type power supply that has a very accurate 60Hz.

Is there a version of the Hammond organ with a tone wheel box designed for 50Hz that was sold in Europe ?

[WhopperPlate]

I have been increasingly curious if the 50Hz to 60Hz will have tonal impacts on my Bandmaster.

40:56
https://youtu.be/rNvOUmwPiUQ

[WhopperPlate]

If you think you can hear a difference in tone between 117Vac and 120Vac, you certainly do hear it. Other people may or may not be able to hear it, though.

If you think you can hear a difference in tone between 117Vac and 120Vac, you may be blessed and cursed with incredibly fine tonal perception. The blessed and cursed is the same thing. We commonly have variations of more than 3Vac in our mains power voltage at different times of day. Unless you can actively regulate the voltage, you're going to get changes unless the UK is much better at keeping it constant than we are in my part of the USA.

Until I began utilizing voltage regulation when I would perform live music I would constantly have good nights and bad nights .

I remember hating myself after gigs wondering why it sounded like crap, especially after dedicating hundreds of hours into dialing in a tone . Band sounds great at rehearsal, and like amateurs at the show .

And then I starting regulating the voltage for the whole band. At that point bad nights weren’t there, in fact we began playing our best at that point . After that long saga I personally will never underestimate the effect +-1-5vac has on electronics.