Tip! After two decades in the experimental music scenes of New York and Western Massachusetts, Wednesday Knudsen might be known equally as a sought-after improv collaborator and the vocalist and guitarist for the beloved long-running psych band Pigeons, as a member of the New England folk rock ensemble Stella Kola, or the psych kraut supergroup Weeping Bong Band. Atrium, is Knudsen’s fifth solo album, marking her rich recording history with a stunning masterwork. Channeling the “atmosphere of pr…