Measuring pitch/CPS by vibrations through wood vs. air which should be more accurate?

There are three types of music tuners that measure pitch or more precisely CPS (cycles per second or Hertz). 1. uses a microphone to capture the sound that passes through air 2. clip ons attach to the headstock of the instrument and the sound passes through vibrations in the wood. 3. direct electrical connect through a cord.

I’d like to know in theory which medium would more accurately pass the sound? Air or Wood?

Which transducer would potentially be more accurate? a microphone or whatever the clip on uses to detect the sound vibrations? I’m not sure what the heck it uses for a transducer.

Am I right in thinking all three methods are analog? The tuner would have a Analog Digital convertor chip inside? Something similar to this Texas Instruments IC? The quality of that chip would make some difference.

Typically the microphone style is found in the cheap chromatic tuners or guitar tuners. Korg makes a chromatic and a guitar tuner for under $20. But there are a few high dollar tuners with microphones. Like the Boss TU-12’s. They are $100.

The clip-ons are in a similar price range. You can get a cheap one for under $20 or spend a $100 for a quality Peterson StroboClip Clip-on.

Apparently the manufacturing costs for the two styles is very similar.

I forgot to ask about environmental factors. Would the sound of a pc’s fan or the central air conditioning adversely effect a tuner with a microphone? Would the effect be the same for a clip-on?

It seems like the sound from the central air conditioning or a PC’s fan would strike the guitar’s wood just like it strikes the microphone. But I’m not sure how much difference there is. I know that I can’t tune my guitar with a microphone tuner if someone is talking at a normal level. It doesn’t seem to bother the clip-on as much. But, I wouldn’t want to tune if the band was rehearsing loudly with a drummer. Those vibrations would travel through my guitar’s wood and would probably throw my tuning off. (I haven’t actually tried that.)

If you’re just measuring the pitch of the fundamental frequency (and you don’t give a hoot about the harmonics), then either should work equally well. If you excite air at X Hz, it will vibrate at X Hz, and the same will be true for wood, or any other material. Different materials may attenuate the amplitude of the frequencies they transmit, but they won’t alter the frequencies themselves, and frequency is what your tuner responds to.

For a mic that’s listening to your guitar neck’s wood or is placed directly in front of the strings/soundbox, the guitar will be the loudest thing, unless you’ve got a raucous party going on in the room. The farther away the mic is, the more your guitar will have to compete against ambient sounds, which will confuse the tuner. I recall that in high school band, the whole band had to stay fairly quiet while each instrument played a pitch for the tuner; this was because the tuner stayed in one spot in the front of the room, and everyone stayed in their seats.

I’ve been trying to recall my thirty year old physics classes. I think sound passes through a medium? It can be water, air, wood or many other materials. It probably doesn’t effect the pitch or cps. I just wanted to check.

Real world, I started with a cheap $20 Korg guitar microphone tuner and found it lacking. Common notes in my chords weren’t in tune with each other. I’ve started using a $90 Peterson StroboClip Clip-on with much better results.

While they may both theoretically be the same, I would say that measuring through the air is guarantied to be an accurate representation of the sound we hear for obvious reasons.

But the issue isn’t “sound”, it’s “pitch”, i.e. vibrations per second. I think wood is a better conductor of vibrations than air. And with a tuner clipped on to the headstock, you can tune regardless of how loud ambient sound is.

In general, a sound vibration doesn’t change pitch when it travels from one medium to another. However, it can definitely change amplitude, due to differences in the acoustic impedance of the two media. Moreover, notes produced by any instrument more complicated than a tuning fork are complex combinations of many different harmonic frequencies. The transmission from one medium to the other might transmit some harmonics better or worse than others, which would lead to a change in the timbre of the note but almost certainly not its pitch.

The one exception I can think of is if the transition from one medium to the other caused the fundamental frequency to be severely damped, leaving only higher harmonics. In that case, you might perceive the fundamental to be an octave higher, a twelfth (octave + a fifth) higher, two octaves higher, etc. But that would be something you would hear instantly; it wouldn’t cause a small shift in the pitch that you could adjust with a pegboard.