My BAUD arrived today. My first impression on handling it was that, for something so expensive, it's very cheaply made. Once I started using it, the first impression was confirmed. The housing is flimsy. The battery compartment is difficult to open, and doesn't seem like it will hold up after many openings. The knobs are a bit jiggly, probably because they're mounted on a flimsy housing. The volume knobs, rather than giving you a smooth increase, cause sudden, discreet jumps in volume as you turn them. I'm disappointed that there are two separate volume knobs rather than one for volume and one for balance, but I suppose that if the balance shifted in jumps like the volume did, it wouldn't have been an improvement.
I agree with @Forbearance that the minimum volume was a bit too loud, but I was able to manage it. It seemed like the volume decreased as the frequency increased, but that could be a function of my hearing profile (which isn't bad at all).
The process of tuning in to the right base and beat frequencies was quite challenging. It's going to take some practice to get the hang of that. I'm been a knot of anxiety all day, I guess in anticipation of arrival of the device and worrying about whether I'll be able to figure out how to use it, whether it will be effective, and whether I wasted a lot of money on this thing.
I'll continue posting my experiences here.