<html> <body> Robert, Earplugs help to focus you on what you want to hear.  The canal caps sold by Diane Hofsteter (dpno2ur@yahoo.com) are ideal and will protect your hearing over the long term.  The Music ear plugs sold in you local drug store are inferior (attenuate unevenly, too much high up) but will do as you start out. A Coleman Beat Counter is good to help with the learning.  It will show you where to listen for a given interval.  Each note, like a beam of light, is made up of a symphony of partials.  With practice you will begin to use your ear as a prism to split out the coincident partials you are wanting to tune or count.   Say, for example, you want to practice tuning a 4:2 octave, and you are tuning C5 to C4, tap C6 and then listen at that frequency as you play C4 & C5 together.  You will then hear the beat you are using to tune that specific type of interval.  Typically I don't count thirds and sixths.  I just "feel" when they are right and that they progressively speed up as I proceed up the middle of the keyboard.  There are a variety of tests that can help you arrive at good relationships between intervals. What course are you taking? Good luck, Andrew At 10:04 PM 3/11/2005 -0500, you wrote: <blockquote type=cite class=cite cite>I have just started to study piano technology with a correspondence course, and one of the text books suggests that it is necessary to recognize beat rates of 7, 8 and 9 beats per second in order to tune certain intervals such as 3rds and  6ths. To me this seems extremely subtle, and I am wondering whether most people can tell these beat rates apart just by listening? At the moment I am having difficulty even hearing the beats in the first place, and was wondering if anyone can suggest how they can be made to be more pronounced and easily heard?   I don't have much problem with unisons. I can hear the beat rate slow down when the frequency of one string gets closer to the other, and then the quality suddenly improves (probably by sympathetic vibration?) when I get a good unison.   Does one's ability to hear beats and to determine their speed improve with experience? Thank you for your advice.   Robert Finley</blockquote></body> </html>