Need to adjust the speed every time I turn on turntable

glennewdick

one thing to consider is your power going to your house changes a few volts all the time that alone will throw off a turntable with out compensation.

No, it won't. Turntables don't rely on AC voltage for speed regulation. The ones that use AC motors are synchronous to the line frequency, which is subject to only very tiny deviation by the very nature of AC distribution systems. Those that use DC motors employ regulation in the DC power supply.

Okay here's another thread where obviously mijostyn and clearthink want to talk about things other than audio, so I'll exit here. I guess these guys are really amused with themselves.

mijostyn

AC is the preferred way of transmitting electricity to customers because it is way safer, more efficient and lower maintenance than DC.

Oh no, AC is not safer than DC - that was Edison’s argument when he was battling it out over power distribution. That’s why Edison promoted the electric chair. It’s all in the history books.

sleepwalker65

AC frequency, which before accounting for noise from other sources can vary by up to +/-2Hz ...

Please explain how noise affects AC frequency and how you arrived at this spec.

Noise that breaks the synchronization can increase this to 10% depending on the power factor of the source.

If that were true, the entire connected electric grid would collapse. The function of the AC frequency is to allow multiple electric sources to be connected and work simultaneously on the same grid.

lewm

Cleeds, As I recall, from reading those very same history books, Edison promoted DC electrical transmission

Exactly. That’s what I wrote. Edison promoted the electric chair to warn about the dangers of AC. All of Edison's early electrification work was DC, such as in NYC, where he ran some of the wires himself.

@lewm I see now that what I wrote was completely ambiguous!

If Edison had won the point, we wouldn’t need rectification in our audio equipment, but on the other hand the DC voltages available for B+ would in many cases need boosting.

We’d be in a different world if Edison had prevailed, for sure. For one thing, we’d probably be paying a whole lot more for electricity. I think the main reason AC prevailed is because of distribution efficiencies.

Oddly, solar electricity is DC. Edison would have liked that.