Reginald Smith Brindle wrote the Guitarcosmos series (published by Schott) and longer works such his Polifemo de Oro, recorded by Julian Bream and others.

The studies contained in Volume 1 of Guitarcosmos are very varied. As the composer states in the introduction: ‘There is tonal music, and atonal music, pieces using whole-tone and pentatonic scales, modal music, bitonality, serial techniques and music in the style of free dissonance’.
As played by Julian Bream, Smith Brindle’s music is imbued with a very wide tonal spectrum. By playing these pieces on a short-scale classical guitar of 60cms string length, strung in gut trebles and silk basses, and plucked with just the flesh of the fingertips, the tonal pallet is more muted. I actually prefer this restricted range as it focusses the attention more on the intervalic relationships within a piece, and brings out an almost Renaissance lute-like quality which you may or may not find attractive.
Eight Little Canons No.3 [Page 8]
Eight Little Canons No. 4 [Page 9]
Four Chromatic Melodies No. 1 [Page 11]
Simple Serial Melody [Page 24]
Artificial Harmonics [Page 29]
Here is a wiki page on Smith Brindle, and a Guardian Obituary.