At 05:01 PM 11/13/1999 -0500, Patrick wrote: >Dear List: >A couple months ago I queried the list for help in diagnosing an >intermittent buzz in a Steinway B. While that piano presently seems to be >behaving, I have (occasionally -- over the past 20 years) continued to >encounter mystery buzzes in a few other pianos. > >Has anyone developed a flow chart approach to this multi-variant problem >("Step A: Look for visible stuff on the soundboard. Step B ... Step Q: Bill >the client for the time elapsed, start driving home ((be sure there are >some brews in the fridge)) ...")? Does a stethosope help? > >Frustrated, > >Patrick Draine Well, Patrick, frustration goes with the territory: well-nigh universal in noise searches. Okay, I'll jump in and start a flow chart, for finding noises in grands. Of course, I'll miss a lot of things. Maybe other people can fill in the gaps, change the order, contest the methods, etc. (Sorry if this all seems so obvious as to be dopey.) 1. Hear noise or have customer complain about noise. a. if customer complains, have them produce the noise if they can. If they can, move on to 2. a1. If they can't make the noise happen, tell them, "It went away because I'm here, like taking your car to the garage and it runs perfectly." Then get them to describe the noise and the conditions when it occurs, and move on to 2. 2. Try to make the noise worse, by playing loudly, shaking case parts, rapping or slapping the case and board, flexing the lyre, etc. If you can make it worse, you probably have a pretty good idea where it comes from. 3. Once you've got the noise dependably there and bad (if necessary by having the customer playing loudly while you walk around and explore) see if you can get it to go away. a. listen while walking around, trying to see where it's coming from, being aware that some sounds are referred, and seem to come from somewhere other than where they start. b. start laying hands on things, pulling at things, getting to odd places in the piano. For instance, lie on your back under the piano (maybe making a crack about your totally undignified position) and press on ribs, cracks, soundboard. Explore that little shelf near the rear leg. Pull sideways on trapwork. Get up and press the hinge near the tail, and the continuous hinge on the lid. Check the lyre props, the lip props (see if there is cushioning under the short stick). If necessary, pull the action out and check the dampers, the underlevers, the damper tray, the sostenuto assembly. Check for debris on the soundboard. Keep checking until you've located the darned noise. 4. Remove foreign materials and objects, if you've found any. 5. Once you have some idea where it is coming from, make it go away. a. if hard things are rattling, tighten attachments or muffle with cloth or felt or leather. b. if screws are overturned, use leather and white glue in the holes to tighten them c. if the long hinge is rattling, and you've checked the screws, sometimes it quiets if you give a little tap to move the long hinge pin a little. d. if case parts, especially polyester case parts are groaning and creaking, try lubricating the joint. If the parts are removable, smear VJ lube where the interface is shiny. If parts aren't easily removable, there is something I've done, but it is too easy to muck up, so I don't feel like describing it. e. on the keybed, use only dry lubricants like talc. For the areas where the glides contact, I use a 6B (very soft) pencil to rub across the contact area, where the glides have made marks. f. if cracks are buzzing, the board has to made fast to the ribs again. Others can say how to do this better than I. g. if seams, such as the rim-board interface are buzzing, sometimes some CA glue can be wicked in. Careful where it ends up. h. don't forget the room: light fixtures, picture frames, bric-a-brac, etc. i. while you're being a hero, get the bench quiet. Refer to my Journal article if you don't already know how to do this. (Nov. 97) 5. Try to be modest, and let your customer do the exclaiming. Yes, I know, it's hard. 6. Accept reasonable remuneration, laugh all the way to the vehicle, consider writing up your discoveries for us here, or for the Journal. Epilogue: If you get depressed and discouraged and _must_ admit defeat, go back to tuning and think about it. Then repeat 2, 3, 4, and 5 in the light of your new theorizing, until the light dawns. I suppose that sometimes you simply CAN'T fix a noise, but I feel that it's worth losing some time by being stubbornly persistent, if need be on a subsequent visit, simply because that's how you learn to fix obnoxious noises, and every time you win you (a) feel great, (b) impress the heck out of your customer, who may have tried several of your colleagues without success, and (c) have a new weapon in your noise arsenal. Idle theorizing: every noise comes from motion of some kind or other. Something is moving against or colliding with something else. Locate the motion, and muffle it if the parts _need_ to move, or immobilize them if they don't, or lubricate the rubbing surfaces if they can't be totally immobilized .... exit noise. Standard action noises: they are always present, but can either start to bother a player who suddenly pays attention to them, or they can get worse with wear. When actions wear, parts get looser and/or cushioning materials pack down and fail to cushion. Restore tightness and cushioning, and they will be as quiet as they were to begin with, which often isn't very quiet. Trying to explain to a customer that what they are hearing is normal is the hardest noise-abatement procedure of all. --------------------------------------- Not exhaustive, but exhausting enough reading for today ... sorry if this seems totally elementary. And I've never known a stethoscope to help, but others swear by them. Susan P.S. I just found how to stop a stubborn creaky shift pedal noise (at the end of the action return), on the third try. (An Aeolian grand.) I had lubricated, checked out, done everything from the pedal to the action pins. Third try, 6 months after the first one, I found that the keyblocks were creaking against the keybed. Try 1 had worked for awhile, because I had put talc on the keybed, but it wore away. I looked at the underside of the keyblocks, and found that they didn't meet over the whole surface, and where they did meet was shiny. Some other tuner had added an extra screw through them into the keybed from the top, behind the fallboard. I didn't understand this when I first saw it, but now I suspect that he saw the blocks were moving a little during shift. The extra screws still didn't immobilize the blocks enough to stop the creaking, though they didn't visibly move. VJ lube on the shiny places stopped the noise at last.
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