Mellotronists

-kraftwerk (yes, they sure did use one)

Sorry no - this was the Orchestron if you're referring the mid 70's period.

--the isley brothers - yes on Don't Say Goodnight 1980.

The mellotron probably belonged to the studio.

It makes a difference. If you own a mellotron, you have more time to come up with some innovative playing techniques than if you spend just a few rushed minutes with it in a studio setting.
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