50 Hz Solid-State Amplifiers Powered By 60 Hz AC?

[Ron Resnick]

I have been researching AC line frequency and high-end audio solid-state amplifiers.

The question is: is there any problem or issue (electrical, sonic, thermal, safety, etc.) whatsoever with feeding a 60 Hz AC line frequency to a solid-state amplifier designed to operate at an AC line frequency of 50 Hz? (Obviously the amplifier designed for 50 Hz must be fed the AC voltage for which it was designed.)

The answer seems to be that the steel core of a transformer designed for 60 Hz AC which is powered by 50 Hz AC can be saturated and draw excessive current and the transformer can overheat. However, a transformer designed for 50Hz AC which is powered by 60Hz AC experiences reduced idle current and actually runs a littler cooler when powered by 60 Hz AC.

So, my tentative conclusion is that there is no problem whatsoever powering a solid-state amplifier designed for 50 Hz mains with 60 Hz AC.

Do you agree?

Thank you.

 

[opus112]

Agree.

 

[Speedskater]

If the line voltage is correct then 60Hz places less demands on the transformer than 50Hz.

 

[spazmatron]

you should be in profit here so to speak, problems come the other way..

 

[microstrip]

One unfortunate frequent issue when using power transformers designed for 60 Hz with 50 Hz is mechanical hum, that can be very disagreeable. When operated at the higher magnetic flux due to the 50 Hz transformers heat more and can exhibit resonances that could not be detected at the manufacturer tests. I have inquired several US high-end manufacturers who told me that they were not able to test their gear at 50 Hz.

Unfortunately the recent PS Audio power regenerators (P10 and P5) do not have the capability of generating 230V 60Hz - the older ones could and were very useful.

 

[Ron Resnick]

Hi Microstrip,

So do you agree there is no problem whatsoever powering with 60 Hz AC a solid-state amplifier designed for 50 Hz mains?

 

[Speedskater]

Is the 60 Hz voltage correct for the amplifier. (name plate value)?

 

[Ron Resnick]

Yes; I would be powering the European equipment designed for 50 Hz with 240 VAC.

 

[Speedskater]

Yes, almost all US homes have 240V available for appliances.

 

[microstrip]

Hi Microstrip,

So do you agree there is no problem whatsoever powering with 60 Hz AC a solid-state amplifier designed for 50 Hz mains?

Yes, you should have no problems - in principle you will have the best of both power conditions - higher voltage, reducing current in the primaries and power lines, and an higher frequency, that reduces maximum flux in transformers, making them more efficient. Also ripple voltage in the power supplies is a little lower at 60 Hz, a good thing, although I doubt this has any effect in sound quality.

BTW, AFAIK the US 240V is intrinsically balanced - another positive aspect.

 

[Barry2013]

Yes, almost all US homes have 240V available for appliances.

I'm curious and a little puzzled as I had assumed that it was almost exclusively 110 volt supply in the USA.
Would you mind describing the position in the US more fully please if only to satisfy my curiosity, though I am sure others would be interested.

 

[Speedskater]

It hasn't been 110V in over a half century. Then the typical line voltage moved to 115V then quickly to 117V and on to 120V. But now it's heading towards 125V. All new parts and pieces have a 125V rating.
But almost all homes have a 240V (for now) center tapped single phase supply. The center tap provides two 120V legs or poles. Which are often mislabeled phases just to add to the confusion. The 240V is for the major appliances, heating & cooling, hot water and clothes drying. Most everything else is on 120V.

Note that legacy hi-fi equipment designed for 110V may have unhappy power transformers when connected to 240V.

 

[Barry2013]

Thanks Speedskater.
I guess it would be something of an upheaval to move to 240 volts like the rest of the world (or most of it) but it would be good to have a common global voltage.

 

[Atmasphere]

How things work dept:

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If the power transformer works on 50Hz it will be no worries whatsoever on 60Hz but not necessarily the other way 'round.

 

[Ron Resnick]

Thank you, gentlemen.