Zsy, I'm not so much concerned about the quality of the sound as I was about the controllability of the pitch. Besides, I don't think you meant exactly what you wrote, because if it was a perfect sine tone it would sound boring! The Etherwaves have a knob to set the timbre between saw wave and square wave, but I don't think you can get a sine out of it
Anyhow, I got a new Etherwave a few days ago. There was an older one available on craigslist but I went for a new one because of this thread. And I think you guys are right. I first played an Etherwave about 4 years ago, and it was very hard to stay on pitch. Then my school bought a Pro, and it was so much easier that suddenly I felt like a player. Then I finished school and had to buy my own theremin, but couldn't afford a pro, so I got a new Etherwave.. and it's great!
I'm kind of a geek so I'd really like to know what electrical changes might have been made in the newer Etherwaves to make their pitch response better. Any information would be greatly appreciated!
Happy playing guys :)