Occasional hum

[CageyH]

Is this more to do with the fact you know it's there rather than the impact on the music then? I'd try and live with it for now and you might forget about it.

Totally.
I don’t believe there is much impact on the music, but I want to minimise stray signals in the phono stage.

[CageyH]

I think I have actually nailed it.

It has taken long enough….

[Barry]

In the end, what caused the hum?

[Lawrence001]

I think I have actually nailed it.

It has taken long enough….

Rather enigmatic [emoji23]

[CageyH]

In the end, what caused the hum?

Either the fridge/freezer (Samsung “digital compressor”) or the Fridge, or the Freezer.
Ferrite beads fitted on all three and the level and occurrences of the hum has dramatically decreased.
At normal listening levels, I can no longer hear it. If I wind the wick right up, you can just about make it out.

[CageyH]

Actually, I give up on tracking down the cause.
It is back with a vengeance….

The AG1500 is going in, and staying in for the foreseeable future.

[CageyH]

And my AG1500 is showing me that the AC is varying wildly from 221 V to 232 V as I watch the input voltage.

[Jimbo]

You got some massive power user near you. One of my mates monitors his electrical supply voltage and it sure takes a dip when his next door neighbour switches on his electric furnace!

[CageyH]

We have a couple in the area.
Cereal collection points, where I believe they also dry the grain.

Either that or the AG1500 is playing up.

[JimC]

I know you're convinced it's Mains borne, but.............

Is it a constant Hum/Buzz or intermittent. You have mentioned (and the title of the thread is ''Occasional.....'')

Could it be an Internet Router?
Cordless 'phone and Base station? They send int't signals out to one another to check they're still 'there'.
Mobile 'phone? These int'tly send/receive short bursts of info.

All the above can be picked up by Phono Stages, especially Valve ones.
Try unplugging everything for a night or two, you'll like going off-grid !!!!
Then plug things back in one by one until the culprit is found.

Just a suggestion, all worth a go.

J.