Hi Angus, I am a piper but I learnt the pipes in a British Military Pipe band a long long time ago. Our drummers had the rope tensioned drums. they had leather loops around the ropes which were pushed down to increase the tension (poor description, but I know you didn't need a description). There were recordings on vinal in those days, so you will probably have to find recordings from the 50's or 60's that have been redone on cd's. I think, when a recording has been reformatted in digital, they tell you the date of the original recording. I had a few LP's of pipe bands from that era, but they were stolen out of storage in the UK when I came over here. It was a nice sound. Not nearly so sharp as modern drums.

Hope you find some.

Peter