ETD as crutch: grrr (practical advice)

[BobDavis88@AOL.COM]

Awright, awright, if I'm going to grumble, I'd better offer some practical 
advice, so here I am responding to my own mail (talking to myself again...). 

Anyway, rather than debate whether an ETD extracts vital bodily essence when 
used by a beginner, here are four VERY practical examples of its use to speed 
progress in basic skills, all of which take longer to describe than to do. In 
none of these exercises does calculation within the box take precedence over 
your aural judgment - it is used to see if you are doing what you mean to do. 

1. Use it check your tuning lever technique
2. Use it to check your ability to set A4 to 440 Hz.
3. Use it to check octave width preference and repeatability
4. Use it to check your ability to set contiguous 3rds

Specific instructions. Use a good piano, not too old, so the strings will 
render:
1. Block off one string of a unison. Whack until stable. Zero the ETD to one 
string of the two remaining. Detune the other by no more than a beat or two. 
Close your eyes, or if you are feeling morally weak, turn the ETD away. 
Retune that string aurally with soft blows, until your ear tells you the 
unison is right. Turn the ETD around, block off the reference string, play 
the test string, and hope the display is not moving. Now whack the note, and 
see if it holds up. If it doesn't, your lever technique could use work.

Retune the same string aurally, then push the pitch up and down VERY gently 
(not trying to turn the pin) while watching the display. Does it appear to be 
as easy to "bend" the pitch the same amount up as down? While a hard blow 
might be necessary for bridge rendering during a large pitch change, once a 
string is at pitch and rendered through the bridge pins, change of a few 
cents will not cause movement through the bridge, and a test blow should be 
just that. Actual tuning can be done with lever technique. I have found that 
leaving neither upward nor downward bias on the string produces the most 
resistance to pitch change due to both heavy playing and humidity change. I 
don't pound. I recently tuned a pair of pianos used (beaten) all day for a 
concerto competition. I checked them at the end of the first day, and touched 
up only three barely rolling unisons between the two. 

2. Tune A4 to the fork, aurally. Check it aurally by comparing F2/fork to 
F2/A4. Zero the ETD to the fork, then measure the string. Write down the 
difference, whack the key, measure again. Detune the note (if necessary!), 
and try it 5 more times. (Do it on several occasions with differing 
temperatures and see how much your fork drifts).

3. Octaves: Make sure A4 is stable. Tune A3 to it purely by sound, without 
checks. Use aural tests to determine what kind of octave you tuned (2:1, 4:2, 
6:3...). It's likely to be between 4:2 and 6:3. If you are not comfortable 
with this terminology or concept, your aural tuning can not be fully refined. 
Then use the ETD to measure more exactly what you have done, by setting it on 
the coincident partial and measuring the difference between A3 and A4. For 
instance, for a 6:3 octave, set the tuner on E6, the 3rd partial of A4 (and 
6th partial of A3). Play A3 and zero the tuner. Play A4. Measure how much the 
difference is. You can check the 4:2 similarly by setting the ETD at A5 and 
measuring the difference between A3 and A4. Often this octave will wind up 
about 0.6 cents wide of a 4:2 and a few tenths shy of a 6:3. 

4. Measuring the width of contiguous thirds: Having set your A4-A3 octave, 
add in F3, F4, and C#4 until each 3rd beats 5 times in the space of time that 
the contiguous 3rd below it beats 4 times. Now measure the width of the 3rds 
visually to see how you did. For instance, F3 and A3 coincide 5:4 at A5.
Harmonic series of F3: F3-F4-C5-F5- >A5< (5th partial)
Harmonic series of A3: A3-A4-E5- >A5<  (4th partial)
Set the tuner to the coincident partial A5. play F3 and zero (reset the pitch 
of) the tuner. Play A3 and measure. It should be about 13.6 cents higher. 
Measure the other thirds the same way. The figure won't necessarily be 13.6, 
but they should all be the same. In actual tuning there may be some 
adjustment needed because of the differing inharmonicity/stretch of the 
octaves, but I had to say "beyond the scope of this answer" at least once. At 
least I didn't use the word "paradigm."

There are lots more exercises, but most of them are extensions of these. For 
instance, it is entertaining to stack up three [contiguous] octaves and 
measure how the partials relate at various coincidences, and how much you 
have to do aurally to three likable octaves in order to make a likable double 
and triple octave.

All good tuners tune aurally, whether or not they use a box. However, the box 
can be used by tuners of any level to measure whether our intent is matched 
by our execution, to save the ear for fine work, and to refine and speed 
aural decisions. I've been tuning for thirty years and I'm still learning.

Keep on pitchin',
Bob Davis