Hi everyone!
I'm a newbee here, registered yesterday and now learning how things work here.
When watching video-presentation of professional teachers I noticed that many people do not pay enough attention to technical aspects of tuition: audio and (less important) video quality.
Internal microphone of a noisy laptop can ruin your excellent pronounciation. Incorrect arrangement of mic and speakers can also induce severe echo and make Skype to alter the voice trying to reduce echo.
Using a headset in such case would be a better option (don't buy the cheapest one, adding another $10-20 can make huge difference for the quality).
Nevertheless some teachers have excellent setup and they sound as if would seat in the same room. Their investments in technical side of the process will definitely be covered by deservedly higher hour rate :)
