MK Mains Grid Buzzer, eg K4000... how loud ?

If it is a buzzer, it should be basically 100 Hz, or rather harmonics of that. The bleeper types are usually called sounders.

I know, but for some reason I have stuck in my mind the old "buzzer" turned out by Tandy and a power fail alarm. Both were compact oblong piezo electric buzzers... that emitted a shrill pulsing tone.

Also stuck in my mind is "solenoid buzzers", such as the doorbell type which are a "brutal brisk buzzzzzzzzz".

The two sound very different, but as long as loud enough ok.

If it's anything like the mains buzzer on old Goblin Teasmades, it'll be heart-attack-inducing.

Owain

That's what I was talking about - piezo units are usually called sounders, at least here.

A buzzer is usually an armature vibrated by a coil.

Piezo can be as loud as you want - and the actual sound nearer the peak sensitivity of the ear.