<HTML><HEAD> <META charset=US-ASCII http-equiv=Content-Type content="text/html; cha= rset=US-ASCII"> <META content="MSHTML 6.00.2800.1106" name=GENERATOR></HEAD> <BODY style="FONT-SIZE: 10pt; FONT-FAMILY: Arial; BACKGROUND-COLOR: #fffff= f"> <DIV> <DIV>In a message dated 8/20/2004 8:01:30 PM Pacific Standard Time, alanfors= yth@fortune4.fsnet.co.uk writes:</DIV> <BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: blue = 2px solid"> <DIV><STRONG><FONT face=Arial>I was not aware that tuning forks were suppo= sed to have partials or harmonics. Aren't they supposed to have pure tones?<= /FONT></STRONG></DIV></BLOCKQUOTE></DIV> <DIV>Alan,</DIV> <DIV> </DIV> <DIV>A tuning fork vibrating in air does produce a tone which is primarily f= undamental. However, it also produces a small amount of partials 2, 3, and 4= ; at least mine does.</DIV> <DIV> </DIV> <DIV>When the piano keyslip or keybed is used as a transducer, however, more= of the energy from the fork is converted to higher partials. I would be int= erested to hear what Sarah says about using the teeth/skull as a transducer.= </DIV> <DIV> </DIV> <DIV>The AccuFork [electronic] emits a wave which is sort of square-wave-lik= e, in that it contains odd partials in more-or-less declining amounts, with = the third and fifth partials being the strongest. This means that there is m= ore interference (beating) with the upper partials of the note being set, an= d it means that one needs to be especially careful to be using the right bea= t-generating note (F2 in the case of A4).</DIV> <DIV> </DIV> <DIV>I'd be interested to hear what kind of wave TuneLab generates. Cy?</DIV= > <DIV> </DIV> <DIV>Bob D</DIV></BODY></HTML>