In a message dated 1/11/00 5:21:13 PM Pacific Standard Time, tjack@pacinfo.com (Terry L Jack) writes: << Any of you brave souls care to try and explain to this newbe tuner how you determine that a piano is 16 cents flat or 44 cents flat etc. aurally? >> I'd be pleased to answer your question, Terry. Since the advent of Electronic Tuning Devices, "Cents Deviation" has become the preferred way to express nonstandard pitch in technical writing even though something like, "3 beats flat" makes a lot more sense in conversation, especially to an aural only tuner. At A4, every beat per second deviation from 440 equals 4 whole cents. So realistically, you could really only make an estimate that is a multiple of 4 unless it is not a very large amount and you might correctly estimate something like 2 1/2 beats per second, which would be 10 cents. Also, anything beyond 10 or so beats per second would really be hard to count although a good aural tuner can distinguish between faster and slower 3rds up to somewhere around 15 beats per second. In this case, however, they are probably not being counted, just compared. So, if you could count more or less accurately that there are 11 beats between the string and the fork and it is to the flat side, the pitch would be 44 cents flat (to use one of your examples). Beyond that, saying it is a "quarter tone flat", "about 75 cents flat" (meaning that the estimate is about 3/4 half step) and "1/2 step low" are the ways I commonly hear technicians express this in conversation. Once you get this far off, is an accurate estimate of it really important anyway? Once beyond about 5 beats per second or 20 cents deviant either way, sharp or flat, you will have to make 3 passes in order to get a stable tuning. The estimates people use for "overshooting" the pitch (meaning to deliberately estimate the amount to tune sharp or flat so the pitch will eventually come out correctly), work pretty well but they are only estimates and therefore are not really expected to produce a perfect outcome. They are intended to get the piano close enough to a fine tuning that the piano will be capable of accepting one. So, when you are doing a major pitch raise aurally, offsetting your starting pitch 1 beat for every three that it is sharp of flat is what you try to estimate. Of course there can be a smaller deviation, just one beat, for example, so in a case like that, you learn to set your pitch just marginally sharp of the fork. On anything over 20 cents, it will inevitably require 3 passes. Your second pass will reveal places where your estimate just didn't hold up. This often happens in the treble. It is just as easy to overestimate and have the whole thing too sharp to correct in one pass as it is to underestimate. One reason to take a little longer on a carefully planned and calculated pitch raise is a string rendering problem. This is especially true of the treble and high treble. If you simply crank the tuning pin up to where you think you would want it but do not give the key a firm test blow, you may find the pitch fairly close to where it started after pulling in the unisons. You need in the higher end of a piano where that area is excessively flat to pull the string up a few to several beats beyond where you want it and give 3 good firm strikes to the key. It may easily fall down below pitch. You may have to repeat this a few times before it will hold on to it. In some stubborn cases, you may have to pull the string severely sharp, say approaching 50 cents (a quarter step) and give several firm test blows until it stops going flat. Then lower it to desired pitch with just a tweak of the hammer and more test blows to drive flatter. I call that "pounding the piano *into* tune". Effort spent stabilizing the piano on the first or any other of the rough passes will make the fine tuning just a mere test and slight correction of the rough tuning. It will need to be just that to really be a fine tuning. It should go quickly and easily with many notes needing no correction, otherwise it is not yet a fine tuning. If you have a stretch of even a few notes that are still more than a cent or two (even a slight beat or more) flat or sharp of where they should be in the fine tuning, you should go through that rough spot twice. Sometimes, with a difficult piano and time is running out for the fine tuning, if I find a whole long stretch of notes which are still way flat, I will tune the center string up a bit sharp (I use a muting strip throughout the piano on almost all tunings) and "remembering" the amount of crank it took, I crank the outside pins that much, then go through the middle string again and solidify the pitch. This is risky, of course, you can just make things worse if you over estimate and it will be ineffective if you underestimate. But that kind of technique is the one I use to make the whole process work for me, so I can get going to that next appointment and have this one done on time, accurately and stable. I hope this answered your primary question and that my elaboration was enlightening to you. Sincerely, Bill Bremmer RPT Madison, Wisconsin
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