Ralph Towner can play a whole lot of guitar, but last night at Blues Alley he spent at least half of the first set at the keyboard of the Steinway, the synthesizer or a combination of the two.

When he did apply himself to the acoustic guitar he too often tuned in the electronic device for a string section background, various voice effects and even whistling of different pitches. Towner's manufactured sounds were interesting up to a point, but they fell far short of the oddly contrasting complexity and oneness he has achieved with overdubbed studio recordings.

One extended piece began with organ-like synthesizer and devoted a long middle section to percussive piano, out of which emerged a stream-of-consiousness doodling that in turn gave way to a synthesizer coda of ponderous, even elephantine, swing.

Towner's guitar skills, coupled with his fertile imagination and pan-ethnic sources, are quite enough on their own, and one wonders why he cast himself in the role of electronic one-man band.

The opening guitar piece, "Timeless," a John Abercrombie tune, was marred by the warbling accompaniment of the synthesizer. But the all-acoustic encore was a gem, with dry, rubber band-like twangs and deep bass thumps set to an orchestral concept and achieved with pianistic attack. Imagine, all of that from six strings and a wooden sounding box.