The earliest version of Glass Harp formed in 1968 with Keaggy, Sferra, and Steve Markulin on bass. The band gigged in and around the Youngstown, Ohio, area, finding work anywhere from school dances to clubs. This incarnation of the band recorded several demos, and released the single Where Did My World Come From? on the United Audio label in 1969.
Following Markulin's departure (joining his cousin Joe in another successful Youngstown group, The Human Beinz), the band recruited bass player Daniel Pecchio (formerly of The Poppy). Having recorded a new set of demos and signing with new management, the band set out to polish their live act and shop for a recording deal.
The band quickly found a following in the thriving music scene of Northeast Ohio, particularly alongside contemporaries such as The James Gang. Glass Harp was especially popular at the legendary JB's in Kent, Ohio, playing to packed houses during the volatile days surrounding the anti-war demonstrations at Kent State University.
With their latest demos having found the ears of Grammy Award-winning producer Lewis Merenstein, Glass Harp began work on their first album for the Decca label in the fall of 1970. The debut album (as well as the two following studio albums) was recorded in Jimi Hendrix's Electric Lady Studios with Merenstein as producer. With an album to promote, the band soon began getting more high-profile opening spots for the biggest bands of the day such as Alice Cooper, Chicago, Yes, Traffic, and Grand Funk Railroad amongst many others.
Contrary to the tight production and song-oriented nature of their studio albums, the band's live shows at the time demonstrated Glass Harp's ability to stretch out and expand the boundaries of their compositions. While Glass Harp could be very at home with the prog rock bands of the era, they were in fact one of the pioneers of what would later be known as the jam rock genre, with songs many times reaching over 30 minutes in length with extended solo passages and group improvisation.
1972 would be a pivotal year for the group. Having recently released a second album (Synergy) Glass Harp were asked to perform a live concert on PBS in February. This broadcast would become groundbreaking in that it was one of the first to be simulcast on both television and then-nascent FM radio (having been thought lost for decades, this performance would finally be released as the Circa 72 DVD in 2006). More touring followed, playing both supporting and headlining shows from The Fillmore East to The Winterland Ballroom. Later in the year, the band played an opening spot for The Kinks at New York's prestigious Carnegie Hall, receiving a thunderous ovation at the end of their hour-long set (this performance was released as Live At Carnegie Hall in 1997).
Shortly after the release of the It Makes Me Glad album Phil Keaggy left the band to fully devote his songwriting efforts to the burgeoning Contemporary Christian music scene. Sferra and Pecchio continued to perform together as Glass Harp, adding guitarist Tim Burks and violinist Randy Benson. The music of this new lineup took on a more progressive edge, similar to King Crimson and The Moody Blues (while several recordings exist from this period, they have remained unreleased as of 2008). This incarnation of the group lasted into 1973, when Pecchio and Sferra decided to finally move on to other projects, essentially bringing Glass Harp to an end. Pecchio went on to become a founding member of the highly-popular Michael Stanley Band, while Sferra remained very much in demand as both live and studio musician, at the same time writing and producing his own music.
Since the mid-1970s, Keaggy, Pecchio and Sferra have reunited a number of times, including several well received performances in Ohio, and a short tour in 2000. The 2000 reunion tour included a sold out performance with the Youngstown Symphony Orchestra, which was recorded and released as a 2-CD set, entitled Strings Attached.
In 2003, the group released Hourglass, their first new studio album in 31 years. Well-received by fans and critics alike, the album drew on various musical styles that demonstrated Glass Harp's many influences and individual talents.
In 2004, the band went on a short U.S. tour in support of their triple-live album Stark Raving Jams (a collection of various live instrumental and improvisational material from throughout their career). The album/tour served to successfully re-introduce Glass Harp into the jam band scene, in which they are now considered a pioneering group.
Since 2000, Glass Harp's touring groups have included (at various times) instruments such as trumpets, trombones, saxophones, mandolins and violins. Most frequently, the band is joined by keyboardist Chris Queen, formerly of the Athens, Georgia, funk band Mr. Tibbs
The band's original three Decca studio albums have been re-issued twice on CD. The first time was by a German company in the 1990s and more recently by Music Mill Entertainment in 2005. The Music Mill re-issues were re-mastered with bonus tracks and updated liner notes.
In 2006, Glass Harp reunited for a concert to celebrate the release of their first DVD, Circa 72. The DVD is the first official release of their long sought-after 1972 PBS concert, and includes rare outtakes, home movie footage, and a commentary track by the band.