Fraulein Schneider, Cabaret, Hangar Theatre:
"Yet it's the tentative, doomed romance between the world-weary survivor Fraulein Schneider (Heidi Hayes) and her shy, courteous suitor Herr Schultz...that captures our hearts...Frabatta–a man carrying heart on sleeve–and Hayes—the guarded, scarred veteran of too much change—beguile in their light, lilting duets with their hint of Viennese waltz, an antique graciousness foreign to the Germany they now inhabit. Hayes also thrillingly imbues her solos with all the layers of pain and wry wisdom they carry."
-Ross Haarstad, Ithaca Times
Mama Lilly, Hank Williams: Lost Highway, Gretna Theatre:
"...Williams’ Mama Lilly (Heidi Hayes), who is a lovable bit of comedic relief in a story heavy with substance abuse and the rigors of success."
Pianist, Side By Side By Sondheim, Walnut St. Theatre:
“The show is a collection of some of his best-and least-know songs, sung by four good voices, accompanied by two good pianists....But the show ends with a very funny medley – even the piano players sing – and you'll exit humming, guaranteed.
-Toby Zinman, Philadelphia Inquirer
Soloist, Pops Concert, Ocean City (NJ) Pops:
Heidi Hayes manages to wring every nuance from a lyric. Her gestures and facial expressions speak volumes...Later, she broke many a heart in excerpts from Camelot...
Hayes is versatile and makes the jump from grand opera to saloon singer with an aplomb rarely achieved by operatic sopranos.
-Ed Wismer, Ocean City Sentinel-Ledger
Augusta's Friend, Ballad of Baby Doe, Central City (CO) Opera:
The rest of the cast, particularly....Heidi Hayes....as Augusta Tabor's friend(s), were energetic actor(s) and actress(es) and sang extremely well.
-Blair Chotzinoff, KVOD
Soprano Soloist, St. Matthew Passion, Philadelphia Singers:
Local singers included Soprano Heidi Hayes, who sang not only her own solos but also those of the indisposed Doralene Davis...” Hayes...sang her arias with a bright well-projected tone and a fine sense of involvement with the text. She was especially good in the fast passages of Lord, to Thee my Heart is Given.
-Michael Caruso, Main Line Times
Dew Fairy, Hansel and Gretel, Hollybush Opera Theatre (NJ):
In the Dew Fairy's brief solo, Heidi Hayes sings softly and appealingly.
-Robert Baxter, Courier-Post
Second Spirit, Magic Flute, Pennsylvania Opera Theatre:
...the three genii, like goofy street urchins, sang their beguiling music in fine ensemble, preserving individual character in unshakeable togetherness.
-Daniel Webster, Philadelphia Inquirer