DjBobby
1000+ Head-Fier
When I first got the Little Dot MkII, I measured the DC offset on startup and noted that it was pretty high, hence the warning not to use it as a preamp for a DC coupled power amp. The DC current will be amplified by the power amp and blow out speakers/headphones. The preamp output comes off the headphone out directly. I finally read the manual carefully and it said to plug in the headphone before turning the amp on. Not sure if that's a good idea. I made this little video to show why.
Without a load, it takes even longer to stabilize. I would wait for at least 5 minutes after turning on the amp before plugging in headphones.
Thanks for the measurements. Still not understanding why would David ZheZhe insist on plugging the headphones before turning on, to protect the amp or the tubes?
Btw. did you have a chance to measure the output impedance?