BECAUSE THE Discwasher Group distributes Telaro's "direct-to-disc" recordings, at a hefty $16 per disc, one might have inferred that the similarly high-priced Denon records Discwasher is importing from Japan ($14 suggested list) are products of the same process, but they are not. Denon, in fact, inserts an additional stage into the usual tape-to-disc processing cycle and, far from losing quality thereby, has come up with what many listeners consider the finest sound on discs.