Poor sound quality.
Technical:
- The volume changes several times and is very low for most of the video. Volume is adequate from 0:35 to 1:00 but you are too close to the mic. (the 'plosives' of the speech {the "P" and "B" sounds} sound like you ar blowing into the mic.)
- There is also an intermittent hum in the audio.
- The tone (frequency response) makes it hard to understand. It sounds like the Bass is emphasized and the mid-range cut. Usually the reverse is easier to understand.
Presentation: (the pacing needs to slow down some.)
- There needs to be a little more time in between sentences.
- There needs to be short pauses after the statement of each new concept so people have a chance to absorb and understand the idea.
(the pacing needs to slow down some.)
general comments:
Some more detail and/or explanation about Waves and Energy may be useful; it's a hard concept for many people.
In some instances, your enunciation makes it hard to understand some words.
More voice inflection would be useful. Currently the voice-over comes across as 'droning' ("to speak tediously in a dull monotonous tone"), it seems to all run together.
(A few hours with a voice coach or an acting coach would probably help you a lot.)
Well, that's my humble opinion. Don't be discourged though. Around your age I had to practice technical presentations for months to get them believable. You are certainly off to a good start.