Klarinet Archive - Posting 000218.txt from 2002/11

From: b5w@-----.net (William Wright)
Subj: [kl] Tuners, and -- !!! -- materials
Date: Mon, 4 Nov 2002 19:16:39 -0500

The technician at Peterson was indeed very helpful, especially since I
didn't know exactly which questions to ask. (Give credit where it's
due)

==========

Tuners do not pay attention to harmonics above the fundamental (unless
the fundamental is so weak or a higher harmonic is so strong that the
tuner decides the higher harmonic must be the fundamental).

Therefore my thought that losing a higher harmonic would confuse the
tuner were false. The tuner simply doesn't pay attention to anything
above the fundamental under normal circumstances.

One example is when you damp a guitar string below where you are
fretting it. If done properly, this kills the fundamental completely,
and therefore a tuner will show the pitch of the string's first
harmonic.

If a diesel truck rumbles past, the tuner may assume that the truck
noise is the fundamental, even though a 'musical' harmonic structure
does not accompany the truck.

==============

I mentioned in a previous post that, "after I had dealt with other
matters", I became convinced that......

One of the "other matters" is that reverberations, particularly in a
small room, can reinforce or cancel each other, and thereby they can
alter the waveform sufficiently to confuse even the best tuner.

It's obvious that if you're sitting next to the trumpet section, your
tuner may be measuring the trumpets, not you. But what's not so
obvious is that if you're playing alone in your room, your own
reverberations may confuse the tuner. I ran into one example of this
and I corrected it by going outside. I heard birds and auto traffic in
the background, but my tuner was happy again.

Equally as important, sometimes moving either the tuner or the
instrument as little as a couple of inches can cure the problem. (I
should've thought abut this on my own, considering all the conversation
we've had on Klarinet about microphone placement.)

=============

A strobe tuner (in the $300-$700 class, at least) cannot respond to more
than about 120 notes per minute, depending on details. I was hoping
that, when the advertisement said "smooth, instantaneous response at the
speed of light", I would be able to measure how my intonation was
fluctuating as I played at 200 notes per minute. But not so,
unfortunately.

But better tuners include just temperament, accuracy to 1/10 cent rather
than 2-3 cents, etc.

==============

The technician volunteered, without any prompt from me, that instruments
which emphasize the odd harmonics **do** become confused more often
(compared to instruments with more uniformly distributed harmonics)
while identifying low notes. I didn't get to talk with him at length
about this, but the tuner that I'm going to purchase has a "extended
bass" mode. I'm assuming (perhaps incorrectly) that this is to help
deal with the problem.

==============

.....and now for *The Climactic Conclusion*: <very big grin>

When the technician was explaining to me about reverberations, he said
"The easiest cure is for reverberations is one of our clip-on mics."

"Oh," I replied, "where does the mic clip on?"

"On the bell."

",,,,uh, I've been told that the majority of a clarinet's sound radiates
from the holes, not from the bell?"

"That's true, but the vibration of the clarinet's body gives a stronger
and clearer and less distorted signal than the combination of sounds
that may be bouncing around the room. So our clip-on mic is designed
to sense the instrument, not the air."

HEH !!! HEH !!! I cannot describe to you how badly I wanted to
enter into a discussion of "If the instrument itself is vibrating and is
absorbing energy, then material of construction must make a
difference...."

but since it was long distance on his 800-number, and since the
technician's time was valuable and he had already talked to me for 25
minutes, and since he had been 100% courteous to an individual consumer
with 'weird' questions, I said "Thank You" and took my leave instead.

Cheers,
Bill

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