I think Dalit Warshaw (the thereminist in the above video) has perfect pitch. She was a student of Clara Rockmore, and the theremin she is playing is the custom instrument Lev Termen made for Clara in the 1930's. This unique instrument was bequeathed to Dalit and has recently been professionally adjusted and restored by theremin engineer, Andy Baron.
I find the sound in this video very harsh and strident. Apparently no effort was made to record the performance professionally, and the mike used seems to be the built-in electret in the video camera.
From the artistic point of view, my problem with this performance is that the phrasing has no flow to it. I'm all for taking liberties in this kind of "a cappella" delivery but the liberties, IMHO, don't seem to be well thought out and they lack "feel" and sensitivity. Dalit tends to over extend note values too often and for too long, which tends to give a speed-up, slow-down, speed-up, slow-down, pace to the interpretation.
Dalit is not helped by the "rabbit ear" pitch technique she uses, which consists of rapid "pop up" extensions of the index and middle fingers, while vibrato is accomplished by flapping of the fourth and fifth fingers. I don't know where she got this method but it certainly wasn't from Mrs. Rockmore!
Many people have said that Clara's theremin doesn't sound the way it used to when Clara was alive. I think it does. What is missing is Clara!
Eighty percent of the impression created by the instrument when Clara played it came from Clara herself, not from the tubes and circuitry. We should also not forget that the recordings of this instrument we are familiar with were carefully engineered by Bob Moog himself, who used strategically placed studio microphones and high end professional equipment to capture the sound.
Many people have told me that Samuel Hoffman's theremin does not sound the same today when I play it, as it did when Dr. Hoffman played it back in the 1940's and 50's. The fact is, IT DOES.
Nothing at all has been changed on Hoffman's instrument, and by using Hoffman's modified "chicken peck" technique and miking the instrument with vintage equipment, I can make it sound EXACTLY like the instrument we are familiar with on film soundtracks.
If I may quote the late Mae West, "It's not what I say, it's the way that I say it."