Vague description of evening flyer-any ideas?

[Newoldie]

Apologies that my first post has to be lacking in information but I am puzzled as to what I have just seen and heard.
I live on a smallholding about 1000ft up a Welsh border hillside.Local domestic animals are sheep, horses and cattle.There are plenty of trees nearby.
This evening (about 7.30 - dry,overcast,dull) I was "buzzed" by something fairly large which flew overhead twice.
Apart from the fact it was a large flying insect I couldn't see any detail or colour though it gave the impression of being dark bodied.
The most notable thing to me was its sound which was a loud low pitched buzz,lower and louder than a bumblebee.Could it be some sort of moth?

[Dogghound]

Did it have a fast direct flight? a slow fluttery flight? was it round or long?

[Newoldie]

Fast direct flight I am certain of but shape seemed more round than long.
It didn't have the profile of a dragonfly.
Sorry to be short on detail but it took me by surprise and the light had gone.

[Newoldie]

Sudden thought. Could it have been a large beetle?

[Dogghound]

Could be a hornet or horsefly. It may be worth keeping an eye out tomorrow (or next time your in the area). Impossibly to say for sure what it could be, with insect the possibilities are endless.

[triops]

Ticks all the boxes for Geotrupes, the Dung beetle (or Dor beetle). Low hum or buzz, flying at dusk, round rather than long, and probably on the way to a fresh cow-pat!

[Dogghound]

It doesnt tick the fast direct flight though? in my exp these are quite slow and clumsy in flight.