I've designed a 12AX7 (ECC83) preamp circuit and I'm looking for a second opinion on it. It's supposed to have very low THD hence the bootstrap in the plate chain and the LED at the second triode's cathode, acting as a constant voltage source. Some negative feedback i also found essential. So here's my circuit, what do you think? http://s2.postimg.org/6k8njmxk9/Custom_Image1.jpg
