Hours later, I am hearing the I Tube somewhat changed/changing.....I have now turned on AD and the middle position 3D settings. My full speaker system is good enough that the 3D high position is a bit much. I can AB with the I Tube in chain with one DAC, and listen to another DAC minus the I Tube in the change. The difference is subtle but I like the sound with the I Tube in the mix better, when I switch back to my other DAC, something is definitely missing!
As such, I can do the same thing with my headphones, and headphone tube amplifier. The I Tube with the middle 3D setting actually sounds very good, very noticeably bigger sound stage and increased specialization with the I Tube in the chain.....much like the cross feed settings in my jRiver Media Center. I hear no distortion of negative effects listening to headphones this way, it enhances the listening experience for sure. Clieos mentioned it wasn't meant to work this way, but it is sure working for me. I think that the fact I am using Beyerdynamic Headphones, DT880. DT990, and T1, all rated at 600 ohms, is making a difference. Since, doing my IFI Micro upgrades, IFI USB, I Link, Gemeni Cable, and IFI Purifier, none of my lower impedance` headphones sound very good.
I would be interested to hear from others using the I Tube, with a Tube headphone amp, with 3D turned on, using high impedance headphones!
EDIT: My mistake the 3D off position is center, switch down is low position, hope that is clear...my impressions above were with 3D off!
Edited by cute - 1/18/14 at 5:40pm