<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META content=text/html;charset=iso-8859-1 = http-equiv=Content-Type> <META content="MSHTML 5.00.2014.210" name=GENERATOR> <STYLE></STYLE> </HEAD> <BODY bgColor=#ffffff> <DIV><FONT face=Arial size=2>Hello, Brian</FONT></DIV> <DIV> </DIV> <DIV><FONT face=Arial size=3>As I have been working with electronic = equipment also, I have a modular tectronix unit which has oscilloscope, frequency = meter, frequency generator, and a regulated power supply. From time to time = this precision instrument goes to calibration, and I check my piano ET with = the frequency meter from time to time to check for accuracy. I have always = used Yamaha, I am not promoting it, but that is where I have experience. I = had several models, all of them well over US$ 200.00 At least on these = equipments I never had any problem with calibration, they always measured precisely. = If the equipment is well built it will be much more precise than a tuning fork, = reason is that they use as a base for comparison a quartz crystal which is very = precise. As for tunings, I agree with you. I finis my tunings = auraly, and my customers also like that final touch. </FONT></DIV> <DIV><FONT face=Arial size=3>Elian </FONT></DIV> <BLOCKQUOTE style="BORDER-LEFT: #000000 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: = 0px; PADDING-LEFT: 5px; PADDING-RIGHT: 0px"> <DIV style="FONT: 10pt arial">----- Original Message ----- </DIV> <DIV style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: = black"><B>From:</B> <A href="mailto:btrout@desupernet.net" = title=btrout@desupernet.net>Brian Trout</A> </DIV> <DIV style="FONT: 10pt arial"><B>To:</B> <A = href="mailto:pianotech@ptg.org" title=pianotech@ptg.org>pianotech@ptg.org</A> </DIV> <DIV style="FONT: 10pt arial"><B>Sent:</B> Thursday, June 17, 1999 = 8:08 AM</DIV> <DIV style="FONT: 10pt arial"><B>Subject:</B> Frequency = accuracy?</DIV> <DIV><BR></DIV> <DIV> <DIV><FONT color=#000000 size=2>Hi,</FONT></DIV> <DIV><FONT color=#000000 size=2></FONT> </DIV> <DIV><FONT color=#000000 size=2>I have been tuning aurally for = most of the time I've tuned.  When I first started out, I got a chrome plated = steel tuning fork.  It's not very loud, but it seems to be pretty = stable.  I've heated it up to well over 100 degrees, and put it in the freezer = to cool it down, and measured as best I could in both extremes.  It = doesn't move much, perhaps 1 or 1 1/2 cycles from one end of the extreme to the other.  (It's hard to measure, because it starts changing back to = room temperature before I can really get some good "listens".)</FONT></DIV> <DIV><FONT color=#000000 size=2></FONT> </DIV> <DIV><FONT color=#000000 size=2>At work amongst the tuners, we = have 3 tuning forks, and 3 "machines", none of which are over about $200 = machines.  My personal observations to date lead me to believe that the forks are = all very close to each other.  However, the machines are quite different, = one of which actually tunes a piano sharp enough to hear audible beating when = played with another piano tuned with a fork.  (This is when you're = trying to set the pitch at A-440.)</FONT></DIV> <DIV><FONT color=#000000 size=2></FONT> </DIV> <DIV><FONT color=#000000 size=2>My question is, how does one = determine which A-440 is right?  Is there an easy way to do that without finding = an electronic frequency counter?  I can't think of anyone who has = one.  I'm just trying to figure out if real tuning fork accuracy is possible = in a real world.  To what do we pay homage as the "ultimate" standard measuring device?  Who's "ultimate" standard measuring device is = right if they don't agree???  If I find one person with an SAT and one = with an RTC and the A-440's aren't the same, who's right?</FONT></DIV> <DIV><FONT color=#000000 size=2></FONT> </DIV> <DIV><FONT color=#000000 size=2>I'm not trying to be obnoxious = here, but I've been reading about the "big test", and what's involved.  It all = starts with the basic premise that we start at A-440.  It's been = worrying me a bit.  Who's A-440?</FONT></DIV> <DIV><FONT color=#000000 size=2></FONT> </DIV> <DIV><FONT color=#000000 size=2>Any thoughts out = there?</FONT></DIV> <DIV><FONT color=#000000 size=2></FONT> </DIV> <DIV><FONT color=#000000 size=2>Brian Trout</FONT></DIV> <DIV><FONT color=#000000 size=2>Quarryville, Pa.</FONT></DIV> <DIV><FONT color=#000000 size=2><A = href="mailto:btrout@desupernet.net">btrout@desupernet.net</A></FONT></D= IV> <DIV><FONT color=#000000 size=2></FONT> </DIV></DIV></BLOCKQUOTE></BODY></HTML>