not IMO...

I see experimental as something that forces you to perceive music in a different way... like when john cage released a single song back in the day when shit was coming out on tapes and designed the tape to have an erase head after the play head so that you could only listen to the song once.
another example would be zaireeka by the flaming lips... even though it probably isnt considered experimental by anyone... but the album is 4 discs that must be played simutaneously and unless you have 4 of the exact same cd players, you will always have a different lsitening experience because of slight variances in disc player speeds it creates a wobbly effect to the music.

avant-garde is, like in the wiki quote, a theatrical and/or technical exploration into a fundamentalist/extreme aspect of tradition. very often the entire albums are abstractly conceptual where the whole is greater than the individual parts.
for example, mike patton has an album that is called some italian name and the majority of it is merely aural visualization to evoke a variety of emotions. one song I swear is basically him eating cheetos in a vinyl chair inside a cave.
so I find that the difference is someone putting on an art show (avant-garde) and someone giving you light diffusing goggles to walk around town in (experimental).

see, mike pattons album would have been experimental ambience if it wouldnt have been a linear, sequitir journey.... and john cages album would have been normal contemorary composition if it hadnt had an erase head after the play head.