FZiegler wrote:Hlaalu wrote:By the way do search in the forum because this issue has already come up in the past.
It was in Summer 2020, and it was a quite lengthy discussion not perfectly solved as far as I remember. But worth reading anyway: post134167.html#p134167 With some interesting points for me.
Thanks for posting this. Most interesting is the assumption that a mechanical instrument such as the Hammond B3 could ever be "perfectly" in tune. Whether on a grid operating at a target frequency of 50 Hz or 60 Hz, the interconnection frequency is rarely at that exact frequency. Below is an example of grid frequency from multiple sources at a time when a large generator tripped offline and the recovery after other generators increased output. The interconnection frequency reflects energy production and energy usage - if the generators/solar aren't producing enough energy to meet the energy demand, frequency drops below the target frequency, if generators/solar produce more energy than is being consumed, the frequency moves above the target frequency. It's a constant balancing act for what we call "Balancing Authorities" in North America. Motor-driven, the tonewheel generator of a Hammond B3 has some inertia in its design so second-to-second frequency deviations aren't noticeable in what you hear, however sustained deviations in frequency (the chart reflects averages over each minute) affect the overall tuning of the Hammond B3 relative to a defined reference, such as A-440. The effect is typically not noticeable as the deviations are much less than 1 Hz, but put a Hammond B3 on a small barge or boat using a generator for AC, and you might as well be playing a calliope.