Someone wrote a brilliant little bio on rateyourmusic which I will proceed to copy here:
Sonny Zandueta was born in Baguio [The Philippines]. At 9 years old, he was in a band called Octaves (1962). He played drums and vocals. In 1973 he went to Louvain, Belgium where he met Gavin Gervis, a song writer from Los Angeles, California (and brother of Burt Ward, who played Robin in the television series "Batman and Robin"). Gavin brought together Leks Grobben, Griet Vercruysse, Viona Westra, Jan Vercruysse and Sonny Zandueta and formed Stainless Steel. The band played bluegrass around 1973 then recorded and released their folk album Stainless Steel in 1974. All songs were composed by Gavin Gervis with one song “Together” composed by Sonny Zandueta. Gavin returned to Los Angeles in 1974 and Sonny Zandueta while the band members remained intact. Zandueta began writing all the songs highlighting the band’s talents.
Viona Westra was a celebrity having won a national star search singing competition in Belgium. She has a smooth silky voice with a jazz background, known in Belgium through the band, Mad Curry.
Griet Vercruysse has a classical music background in Violin and so was her brother Jan Vercruysse on Flute. Leks Grobben kept the bluegrass roots with his banjo and bouzouki.
Sonny Zandueta added Joris Verdin on piano, Raf De Vlieghere on drums, Roland Kotsch on electric bass and Chris Schraepen on acoustic guitar. The music turned into light rock / acoustic rock.
The band was initially called Windows but dropped the name and simply called themselves Sonny Zandueta and went to work to record an album The Passing Show released in Belgium in 1976; produced by Sonny Zandueta and Liliane Joris. Karel Bogard played a major role as production coordinator, getting the involvement of Dwarf Records, International Bestseller Company and Bart Ven De Laar Music. The band played a warm up act to Kate and Anna McGarrigle (Canadian duo and songwriters for Linda Ronstadt) concert in Brussels.
Belgian Pop Sampler was released by International Bestseller Company in 1976 featuring Sonny Zandueta with "Everything’s Just Wonderful Here".
Sonny Zandueta left Belgium to live in the Philippines in 1978. He recorded “Can’t Make It Alone” and “Keep On Dancing” arranged by Randy Ray, produced by Winston Quintos under Zap Records and distributed by A&W. Backup vocals was Tillie Moreno of Circus Band. The studio musicians were members of Boy Katindig Band. Ananda Marga lead him to record a series of songs sang by Jaqui Magno also of Circus Band.
He wrote “Get It Together” in 1984 and brought it to San Francisco, California. This song was picked up and released in the U.S. as a country song in one of the cuts from "Hollywood Sessions" 1986 by Sunset Records, Hollywood.
[And where is he now??]
Let's start with the later work, The Passing Show. Again, this is a fantastic little folk-based progressive album full of interest for us, completely unknown, but not deserving of it, and with a gorgeous cover painting to boot. Here's the title track as a sample:
Pay attention in particular to the amazing guitar arpeggios or broken chords on the left that Sonny plays behind, on the right, a high soprano grand piano tinkles with its own gorgeous and heartbreaking skills in emotional resonance, and think how sheerly beautiful the whole comes across as, partly when he gets to the Eflat chorus in which his voice is full of reverb or echo. Why does no one today make music that is as purely beautiful and beautifully pure? This song, which recalls the piano style of Elton John, so much supersedes him it's as if "Your Song" was a dollar store plastic ring compared to a diamond from Tiffanys. There is just so much more for the intellectually open mind to hold onto here and mull upon. As well the lyrics are just short of comprehensible, providing another modality to encourage repeat listening.
An immediately preceding track called "Do You Know" features the female vocals that add so much brightness and colour behind his rather charming Filipino accent, which to me recalls the wonderful Giant Step's Benny Soebardja-- please seek out all his solo records, which are quite similar to this. Listen to the CSNY-style strumming action this time on the twin guitars:
Note also that Etienne Reyser, on his blog, wrote a little bio and gave links to four other songs that you can listen to. In this manner you can hear 3/5ths of the record online...
But for those who want a taste of the great Sonny, I am allowed to share his other record in the preceding band called Stainless Steel. It's quite similar, though inevitably, not quite as good.
Listen to the shockingly Comus-like third track, sung by him, called Children:
While the next all-too-fiddly track brings us back to reality quickly with a splash of cold H20:
Similarly the remainder suffers from an excess of folksy, even countryish or bluegrass twanging. Clearly, the masterpiece is "The Passing Show..."