@jarkman I think the brushless ones are supposed to be really very quiet but they also seem to be much more expensive (£60+) and I think they need higher voltages than 5V whereas this was a drop in

Edit: I didn't say what it was in case it was this specific one you were interested in - AliExpress called it a KST DS215MG swashplate servo, aimed at helicopters I think

@fastness Ta. I wonder how much of the noise is really from the cogs bashing together.

@fastness Oh! I'm amazed they can get enough torque.

@jarkman so was I and it might not be accurate - I was reading descriptions on AliExpress so it might be mistaken (or deliberately false)