Here’s a question if all beats are picked(alternately), then what differentiates 3/4 and 4/4 time - that is to say 3 beats to unit measurement instead of 2 beats/four beats for units of four?
This not a beginners question it is a means to open up a discussion about something observed but so far never looked at for the profound physical(at least) facts it displays.
Take a look at the video , watch the picking examples from the beginning to about, 4 minutes in
https://youtu.be/SeqotzwM1uY?t=102 4/4 time eight notes(1and2and3and4and) easily seen even at full speed(think clockface - that is to say clockwise or counter clockwise?
Or this one
https://youtu.be/R9ZFlGDc6hI?t=349 to about to about 6:07
Three beats to the unit measure
https://youtu.be/SeqotzwM1uY?t=230 3/4 time eight note(1anda2anda3anda4anda) much harder to see at full speed
Hint: the vanishing point(the guitar bridge is twelve o’clock and you(the observer) is at six for one angle, the other angle most used is low string twelve o’clock and high string six o’clock.
In straight four time the answer is clockwise rotation(either the elbow or the shoulder or both), but for divisions of 3 repeated beats over 4/4 time the answer is both counter clockwise(first 3 beats) followed by clockwise(last 3 beats) over and over again.
So this means:
For 4/4 time(as defined)
- downstroke starts are clockwise phrases and Upstroke starts are counter clockwise phrases.
a. outside string changes/repeated cycles are clockwise.
b. Inside string changes/repeate cycles are counter clockwise.
Four non 4/4 time units
In non 4 beats to the unit measure of time (any amount) the cycle has to be repeated twice to be complete.
The smallest subdivision physically expressible in non 4/4 time is 6/8 as beats. This not just for the guitar but for everybody involved in the chosen musical expression.
Caveat on one string at high and ultra high speeds it is so far seen to be necessary to go in one direction only (probably clockwise only as I have observed in more than one player) as long as phrase(six beats) stays on one string only but repeats when string is changed after cycle.
When ascending string changes(between two strings) are involved than a change of direction is absolute in alternate picked sequences with counter clockwise motion first.
When ascending to descending 4 string(one note per string) clockwise(Asc) counterclockwise(Desc). This probably means descending strings opposite of ascending string phrases(arpeggiated or otherwise) non 4/4 beat sequences.
You can call it 3/4 if you choose and write it down that way but you can’t play it relaxed that way(in alternating fashion).
This is complex stuff, try slowing the videos down(way down) and turn of the sound to see it.