I note that on the product description page for the RR2150, the word 'only' follows the 60Hz indication.

With some experience living in a 240v 50Hz country, my electronics concern was primarily with fact that a coil's inductance generally means that lower frequency current meets less resistance, and in a transformer, a magnetic fields that rise and fall more slowly transfer power with less efficiency.

I don't know what kind of power supply is in the RR2150, but my equipment at the time used standard multi-tap transformers with solid-state rectifiers that fed an ordinary compliment of capacitors. My solution was to run my step-down transformer at 100v, not 120. At idle, the power supply transformers in my gear remained nominally as cool as they did at 120v 60Hz. But for use, I kept the volume low to moderate. With less voltage to start with, and slightly reduced transfer efficiency, I didn't expect the amplifier power supply to be at it's full voltage nor be able to meet heavy demand.

I would expect the RR2150 to survive and perform well if not pushed, as long as there is sufficient 'headroom' in the power supply design. Caveat: my remarks are a best guess based on the equipment I had at the time and my experience with it. I wish you well.