Manfred Zollner's Physik der Elektrogitarre, observations...

[antigua]

Stratotarts tipped me off to this PDF hps.hs-regensburg.de/~elektrogitarre/pdfs/gesamt.pdf It's a motherload of phsyical analysis of the guitar, conducted by Manfred Zollner. It's like everything we've seen so far combined, and then doubled, and that's probably still an understatement. But... it's written in the German language. Fortunately, I was able to translate it to English, which was rather difficult, given the very large size of the PDF file. The translation is rough, though.

The amount of information in immense, so I haven't got through even a fraction of it, and it's slow going due to the poor translations, but I want to share some interesting information as I come across it, as it has a lot of researched and factual answers to questions guitarists have all the time on guitar forums. 

I've tried contacting the author, Manfred Zollner, to see if there are any plans or interest in translating the volume to English.

***

This excerpt is in regard to string damping, as caused by AlNiCo pole pieces, versus other types of damping. 

This  graph below compares the damping caused by an AlNiCo 5 pole piece at the neck position, 2.5mm from the string (right), versus the damping caused by various grips on the neck, with a hand.

Here is an excerpt:

" Even at low partials should not overestimate
the field related dissipations. For comparison, finally again the influence ofgripping handshown on the decay of the partials
(Fig. 4:57, Left panel). The top curve shows a measurement in which the guitar was hung with a steel wire on the strap button, in
the two including lie-ing curves, the guitar was clamped to the strap button. In the remaining two measurements the gripping
hand closed to varying degrees the guitar neck, without the strings to touch. All measurements were carried out without a
magnetic field. It is apparent that a different dissipation arises even without magnetic field - the present at the guitar neckpalmis
to be interpreted as a resistive attenuator. His energetic (!) Influence on the Sus-tain is substantially greater than that of a
conventional magnetic pickup (right picture)."




I've long believed that the claim "AlNiCo 2 allows the string to vibrate longer due to less magnetic damping" is an overstated benefit of AlNiCo 2 Strat pickups, and while this does not prove that by itself, it does show, rather conclusively, that simply how you grip the neck with your hand has a greater impact than will the difference between AlNiCo 2 and 5. 

If anyone is interested in this PDF, send me a private message. I don't have an easy way to host the large file, and it's probably not legal for me to do so anyhow. 

[stratotarts]

The magnetic field forms a node that reflects waves in both directions on the string. It's because there is an impedance change. The bridge and nut are such reflectors, but the impedance change is more radical - hence most of the energy is reflected. In the case of the magnetic field, only a small fraction is reflected. The non-harmonically related position along the string of the magnetic field causes intermodulation products between the normal and the field induced offset frequencies of the string, as soon as a non-linear part of the signal chain is reached.

[antigua]

"Intermodulation" is possibly a great word to describe the effect that occurs then the pickups are near or far from the string.

Closely related is another observation, that the impedance and intermodulation mostly only effects the first three harmonics:




In the graph to the right, the lowest plot line is E2, the next up is E3, etc.  At the halfway point, 2 seconds in, he puts a magnet up close to the string, near the neck position, and you can see that E2, E3 and E4 are all disturbed to various degrees, in a way that causes their amplitude to rise and fall throughout the overall amplitude decay, while E5 and E6 are unaffected in such a manner. 


The German to English translation is pretty rough. Do you have a guess as to why it's only lower harmonics that are impacted, and not higher ones?