Bostjan Zupancic: MicroMetal is a microtonal heavy metal side project of guitarist Russ Hayes (also known as Bostjan Zupancic). The project consists only of Russ Hayes, performing vocals, playing microtonal instruments, and playing or programming drums.


Russ Hayes, as Bostjan Zupancic, was the guitar player and lead vocalist for Khereb, a Detroit-based heavy metal band active from 1996-2006. Hayes adopted the moniker as he founded the band with his friend Mike Spica (also known as Vinnie Spiegare), to remain anonymous, because he attended a strict baptist school which frowned on rock music, and he feared disciplinary retribution at the school. While performing with Khereb, Hayes created a side project to experiment with guitar synthesizers, microtonal tunings, and the inclusion of instruments generally out-of-place in heavy metal music. Later, while working on Nothing Special, microphones were picking up chatter from some parrots near the studio, which lead to the conception of the world's first multispecies microtonal cyborg metal band, Naegleria Fowleri.


Bostjan Zupancic: MicroMetal utilizes one tuning, known as 19-EDO (19 equal divisions of the octave) or 19-TET (19 tone equal temperament) on all melodic instruments. To perform in this tuning, Hayes uses refretted guitars and basses, fretless bass, and synthesizers that use a QWERTY computer keyboard.


Quiet, Please, an instrumental demo, was circulated in 2015. Some of the tracks were played on college radio[1][2][3][4][5][6][7][8][9] in Vermont and eventually received airplay on private radio in Vermont and New Hampshire.[10]

On July 19th, 2016[11], Bostjan Zupancic: MicroMetal released Vol I, a short album containing 6 regular tracks plus one bonus track to mixed reviews from local press.[12]

On October 17th, 2016[13], Bostjan Zupancic: MicroMetal released Happy Halloween, an instrumental album available exclusively on the Bandcamp website, for free streaming and download.

On March 17th, 2017[14], Bostjan Zupancic: Micrometal released Vol II, the direct follow-up to Vol I to mixed reviews[15][16].

Nothing Special, a longer and more eclectic fifth album, was released December 1st, 2017[17] and received some positive press[18].

  1. 99Rock WFRD Homebrew, Segment 4, 3:43-6:10, 20 December 2015,
  2. 99Rock WFRD Homebrew, Segment 3, 8:07-10:46, 10 January 2016,
  3. 99Rock WFRD Homebrew, Segment 4, 3:58-6:31, 17 January 2016,
  4. 99Rock WFRD Homebrew, Segment 5, 3:52-6:38, 7 February 2017,
  5. 99Rock WFRD Homebrew, Segment 2, 8:23-11:08, 14 February 2016,
  6. 99Rock WFRD Homebrew, Segment 6, 10:51-13:22, 20 March 2016,
  7. 99Rock WFRD Homebrew, Segment 5, 0:10-2:37, 15 May 2016,
  8. 99Rock WFRD Homebrew, Segment 3, 0:09-6:02, 5 Jun 2016,
  9. 99Rock WFRD Homebrew, Segment 1, 3:31-6:02, 19 June 2016,
  10. 99Rock WFRD Exclusive, aired 4 April 2016 approximately 10 PM,
  11. MusicBrainz website,, retrieved 20 Sep 2016
  12. Bolles, Dan, "Four More Local Albums You (Probably) Haven't Heard), Seven Days, 17 Aug 2016,, retrieved 20 Sep 2016
  15. Best, Larry, "Bostjan Zupancic - MicroMetal: Vol II", The Metal Observer, 1 April 2017, [1]
  16. Farnsworth, Chris, "Album Review: Bostjan Zupancic, 'MicroMetal Volume II'", Seven Days, 19 April 2017,
  17. Amazon item page for Nothing Special by Bostjan Zupancic: Micrometal.
  18. Small Town Loud Album Review: Nothing Special by Bostjan Zupancic.