Eddie Harris is one of those fellows who just can't leave well enough alone. He used to be known as a fair to middling saxophonist and composer - remember "Freedom Jazz Dance" and "Listen Here"? - but somewhere along the line he got the idea that people would also gladly pay to hear joke and dabble with the lates electronic equipment.

It is a mistaken notion. Harris, who is appearing through Saturday at the Showboat Lounge in Silver Spring with a group that is long on gimmicks but short on talent, was mildly appealing as a vocalist on the novelty blues tunes, "I Need Some Money" and "That Is Why You're Overweight," but his opening night experiments with synthesizers and other musical toys were disastrous - and quite coolly received.

"I'm into some new stuff," Harris told the crowd a few minutes after drummer Norman Farrington ended a percussion solo by sitting on a whoopee cushion, "cause this is the electric age." That's presumably the reason a guitar synthesizer, drumkit with pitch-bender, Moog and six-string bass now octave divider that Harris himself has been playing for several years.

Each of these instruments may be, as Harris puts it, "another breakthrough," but you wouldn't know it from opening night's desultory performance.