This is a multi-part message in MIME format. ---------------------- multipart/alternative attachment Ed, I'm an infrequent poster, but a very loyal reader. So, here goes, I've had a lot if success in eliminating or at least reducing the kinds = of false beats you describe by using one or both of these techniques: 1) Tapping the bridge pins moderately. I use the Schaff handy-hammer = (world's "cutest" tool) in the combo handle. I strike each bridge pin, = and listen to the sound that results. A solidly seated pin has a clearly = evident finality to the sound, very similar to that which one hears when = driving a nail into a board. When a nail has been driven to its complete = length, the impact sound changes, and one knows from listening that the = nail is firmly and completely and correctly driven in. Bridge pins have = similar sound properties when firmly seated.=20 I strike the pin with a 1/8" piece of brass rod, about 6 inches long. I = am careful to angle the rod so that it follows the angle of the bridge = pin, so when I position the rod on top of the pin before striking it, = the rod and the pin form a straight line. It is always at an angle from = a line that would be parallel to the soundboard or bridge cap. I = "calibrate" the force needed by listening to the sound of the impact. I = start with a very light blow, sometimes, the weight of the handy-hammer = is sufficient, other times, a little more force is needed. The impact = sound will tell me. Related to the impact sound, is the feel of the impact. A solidly = bottomed out pin feels solid, also as does a solidly driven nail. Were I = practicing to learn the impact sounds with nails and a piece of scrap = lumber, I'd try it by starting the nail with a conventional hammer, so = that it's going in perpendicular to the lumber. Get the nail into the = wood so that there's enough of it in so that it won't bend on subsequent = blows. Finally, drive the nail home into the wood, using consistent = force, and be sensitive to the change in sound and feel of the impact as = the nail bottoms out. Experiment with brads, and with smooth, headed = nails - not too thick or long. Drywall nail screws don't provide the = same feel or sound because of the thread on the shaft. Then, after doing enough of the nail calibration exercise, I'd switch = over to the piano, and proceed in a similar fashion as described above. = Start gently - just letting the handy-hammer drop of its own weight onto = the top of the brass rod. Listen to the impact sound. If it has a hint = of thinness to it, strike the bridge pin again with the hammer/rod = combo, but this time, a wee bit more forcefully. If the pin was not = seated firmly, this second blow will tell you that by how it sounds. = Then, give it the drop only blow again. If the sound is the same as of = the 2nd blow, then the bridge pin is most likely seated. It might even = move visibly, just as a string does when tapped down. Do all the pins in the offending section, not just the pins for the = offending strings. There just seems to be a better result when I do = that; I often find the pins for non-beating strings needing a more solid = seating. The overall result of doing all the bridge pins in a section so = that they're uniform in impact sound, is that the entire section is = improved. I rarely find that extensive revoicing is necessary, maybe 3 = or 4 hammers need a little touch-up with a Hart chopstick or similar = tool.=20 2) Tap every point of string contact with any bridge, or termination = point. For string tapping, I always tap before the 1st bridge pin, and = after it - just enough to be sure that it's firmly against the bridge. I = angle the rod as described above, so that the wire is being drive = closely into the acute angle formed by the wire, the bridge pin, and the = bridge itself. I judge by the sound of impact, as well as by looking at = the wire. Above all, I want to avoid crushing the leading edge of the = bridge wood. I then tap the string at the contact point immediately to = the rear of the 1st bridge pin. Then, I mentally divide the length of = wire going across the bridge and give a light tap at the 1/3 and 2/3 = length. Then, tapping both sides of the rear bridge pin as before. If = there's a duplex bridge, lightly tap the wire at the apex, so that the = wire is firmly seated on it. To wrap it up, tap each side of the wire at = the hitch pin, so that the wire is firmly seated, and that false beats = that might be coming from the wire segment between the duplex bridge and = the hitch pin are reduced, if not completely eliminated. Be careful with = this tap; it's easy to crack the bronzing around the bottom of the hitch = pin.=20 Remove the action, and tap the string lightly into the capo bar, not = enough to create or deepen a groove, but only enough to insure that the = capo/wire interface is solid. Tap the wire where it crosses the front = duplex bridge (if there is one). Replace the action, and retune the = piano. All that tapping will detune a piano, because of the string = movement that's induced by the tapping. There are other issues involved that tapping won't solve. The most = crucial point here is that the center of the bridge pin must be aligned = with the bridge cap notch. I.e., the notch must drop downward following = the line of the diameters of the bridge pins (both front and rear). I = don't do rebuilding, but there are many of our generous colleagues that = can (a) correct any error that I've made in describing the procedures = above, and (b) are expert in bridge recapping, drilling, notching, etc. Hope I wasn't too redundant; thanks for wading through this rather = long-winded reply (I probably need a good editor!) Best regards, Tom Sheehan, RPT NYC Chapter Tuner of many Grammy winning albums, including "Best Jazz Album of the = Year" for about the last 3 or 4 years in a row, and also many other = category Grammys - Jazz Solo of the Year, Best Jazz Composition, etc., = back to 1979. Began tuning in 1973. Largely self taught, assisted by the = magnificent members of the Boston Chapter - Doc Sanderson among them. = Finest people and the most skilled, talented and generous technicians = one could every wish to meet!=20 Director of Piano Maintenance at Berklee College of Music, Boston, MA = 1975 - 1984 (200 pianos, and 2,000 critics at the end. Inventory value = of about $1,000,000. Trained quite a few technicians, some of whom have = gone on to establish businesses much more successful than mine!=20 Established independent one-person micro business in NYC 1993, after = ending a vice-president job with Yamaha, when the company closed the = showroom and R&D studio next to Carnegie Hall on W. 57th St., across the = street and up the block from Steinway Hall. I've worked with many of the = world's greatest pianists and ensembles - primarily jazz; as eventually = happened in Boston, I'm now one of the preferred tuners for a number of = the more prominent recording studios and concert halls in the City. It = takes time, perseverance, constant upgrading of skills, being assertive = but not arrogant, able to tune very quickly and accurately with noise = problems a frequent challenge. There are a number of outstanding tuners = in NYC, in our Chapter as well as others. It is a privilege to work with = all of them, and to learn from each other constantly.=20 Please post again and let us know what method worked.=20 Ah, yes, sorry but I forgot to mention that there are times when it's = necessary to change strings that are offensive; they might have lost = their pliability. Also, if the hammer is badly grooved, it's always a = good idea to file it down and revoice as needed. Another point to = consider is to chopstick voice right in the groove that is activating = the offending string. Sugar coat it (shallow needle - 1/2 mm or so), = right in the groove, and over the crown - striking point. Can do wonders = for emergency situations in a studio or prior to a concert. Tune = forcefully at all times. Get that string to move over all contact = points, and to have a good balance of tension among the various string = segments. Of course, don't strike a note so hard that something breaks = (although that can happen through no fault of the technician). But = double forte is the minimum, for all strings of all notes. Check octaves = periodically to be sure that reference string (usually the center = string) didn't drift out of tune while pounding in the unisons. It can = be annoying, but retune. Use test liberally - Baldassin's "On Pitch" is = the best reference I found - but I played the book, over and over again = at the piano while doing real tunings. Slowed me down at first, but = really provided excellent organization and reasoning for extending one's = tuning beyond the temperament.=20 ----- Original Message -----=20 From: Ed Carwithen=20 To: pianotech@ptg.org=20 Sent: Sunday, June 20, 2004 5:41 PM Subject: New Baldwin A client of mine has a new Mason and Hamlin BB, 7' grand. He has a = particularly keen ear, and any tonal problems give him grief. The piano = was bought new in 2003. I have worked on it a couple of times, and the = tech from the store has been there once. The problem is C7 through F#7 = notes. On each of these notes there is at least one string that has = wildly false beats. The G7 on up to C8 sound beautiful and clear. = Below the C7 is likewise clear. The C7 and the D# 7 are particularly = bad. In each case it is the treble (right) string that is the problem. = I made sure that the string is tight to the bridge. There doesn't seem = to be any impediment at the v bar. I "delicately" voiced with a = needle, all to no avail. Any suggestions as to cause or cure???? =20 Ed Carwithen John Day, OR ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/0f/f1/43/8b/attachment.htm ---------------------- multipart/alternative attachment--
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