The patient is a 1995 Yamaha C2, and the tone in a particular area of the bass has been bothering a customer. Here's an mp3 file I recorded with my iPhone. It's a diatonic octave being played from around C2. <a href="https://dl.dropbox.com/u/147189/yamaha-c2.mp3">https://dl.dropbox.com/u/147189/yamaha-c2.mp3</a> The sound he doesn't like is most evident on the seventh and eighth notes played on the recording, and the same two notes on the way back down the scale. Can anyone identify the source of the sound, and suggest a remedy? The sound reminds me of a "normal" bass note being played simultaneously with a large drop of water dripping into my tub when the bathroom is quiet. Maybe a little "woodier" than that. And shortened up in duration. The onomatopoeia might be "poink, poink" for that portion of the sound. Depending on what the customer is playing and where I am standing, the sound may be more or less obvious. Neither of us noticed the sound on the pre-purchase inspection. Since the move, he has had a Dampp-Chaser installed. I've isolated it from the dampers, damper levers, and damper stop rail. I've tightened the screws on the hammer shank flanges and checked the hammer glue joints are sound. Hammer mating is good. I forgot to check traveling. I can make the sound more prominent by shifting the action "out" of the cavity about a quarter to a half inch, for a slightly shorter speaking length. Seems to be happening only on the bichords. I've done some delicate single-needle voicing just enough to alter the tone but notice it wasn't diminishing the objectionable sound. I'm hesitant to just jump in and experiment (juice up the hammer?) because it's already got a nice, even, "Yamaha" sound. But are these bass notes just "the way it sounds?" Jim