A set of musical entertainments created at home on the computer using inexpensive and freeware programs, Hentai-Oto-Ma: Last Pieces for Digital Synthesis has now been reissued for streaming or download on Bandcamp. A very small number of CDs from the original pressing are still available, somewhere.


Hentai-Oto-Ma (2001) was made using Coagula Light, a shareware "colour-organ" that interprets digital images as sound spectra (height=frequency, width=time).

The image source for this piece was a pornographic Japanese manga comic: each digitally scanned frame of the comic was interpreted with five different, variable time-frames and pitch ranges. The five sequences of frames are played simultaneously, each subjected to different filtering and panning processes. In effect, the piece is a type of timbral canon, with the same series of tone structures transposed into different frequencies and durations - this can be heard most clearly at the end of the piece.

Left: selected frames from the original comic. Right: Spectrographic analysis of right channel of Hentai-Oto-Ma (0'28" to 0'39") showing images transformed across time and frequency. Click here to hear an mp3 of the above excerpt.

Subterranean Clover

Subterranean Clover (version 2) (2002) is another canon made with Coagula, in an attempt to make two pieces using the same software and techniques sound as different as possible.

This time, a single image of a random spatter of dots was interpreted through every possible rotation and mirror-image, within a very narrow pitch range. This process was repeated across 9 octaves, each voice with a different permutation of image rotations, and each kept within the pitch range of "just noticeable difference" to produce timbral variations upon a single pitch.

Narre Warren

Narre Warren (2003, revised 2006) began life as part of a larger, programmatic work titled Immanence of the Eater and the Eaten. It formed the basis of the concluding section:

...the scene shifts to a carport in Glen Waverley. Two teenagers attempt to foment suburban revolution by channeling the ghosts of Robin Boyd and Iannis Xenakis, and then challenging each other to an apocalyptic game of ping-pong. The activity summons the ghost of Percy Grainger, who immediately devises a free-music machine in the form of a ping-pong table shaped like a three-dimensional Galton board, down which balls may continually cascade according to the laws of probability.

The piece is built upon one of the cliches of traditional musique concrète: the manipulated sound of a bouncing ping-pong ball. A recording of John Rodgers and Erkki Veltheim "playing" ping pong was processed through Granulab, a granular synthesis program. Granulab enables the user to perform in real-time, manipulating the sound through various mixes of user-defined patches specifying how the source sound may be transformed.

For Narre Warren, the recording of this Granulab performance was further developed in AudioMulch, using constant alterations in the filtering and compression of selected frequency ranges.

Anything We Don't Have To Do

Anything We Don't Have To Do (2005) combines two sound sources: a General MIDI library of generic sampled instrument sounds, and amplified line noise from a cheap sound card.

A chance-determined score selects from either or both sources, then subjects the sound to various permutations of processes to pitch-shift, time-shift, and/or digitally degrade the sampled sound. A series of variations rings the changes on possible combinations of sound and process.

The Night We Burned Down Bimbo Deluxe

The Night We Burned Down Bimbo Deluxe (2006) was made from an orphaned "temporary" file which, in Microsoft Windows' well-known way, hung around on the hard drive forever. Whatever data were (ha!) in the file were read as if it were sound data. (In fact, the file appears to contain a garbled part of an earlier take of Anything We Don't Have To Do.) The interpreted file was subjected to four types of randomised filtering through parametric equalisers in AudioMulch, with rapid, randomised crossfading between each of the four outputs.

Maybe it's the low quality of the sound from the original data file, or maybe it's because I'm fifty years behind the times, but the piece sounds uncannily like the sort of tape music coming out of the Westdeutscher Rundfunk studios in Köln in the 1950s. In keeping with this sound, the title refers to the human phenomenon of futile longing for a vanished world.

Hentai-Oto-Ma: Last Pieces for Digital Synthesis - the CD

A small run of CDs with tasteful cover art was reprinted in 2008, for sale or trade at live gigs or for other interested punters. These seem to be mostly gone now, so the album is now available to stream or download on Bandcamp.

Ben.Harper, 2006/16.

© Ben.Harper 2001-06. Recorded in Your Dad’s Den, Fitzroy, Brunswick, Hackney. A Cooky La Moo production, edition number 26.