Ed Packard to the white courtesy phone.

Eric West · From: Portland, Oregon, USA, R.I.P.

Ed, I have a request when you have time.

Inre to two questions:

One. Is there a way you can represent a graph and timeline of the change in pitch on a plucked string over a say one second interval in hz and seconds? (Certainly sharp immediately because of the initial disturbance.)

Two. Vindictivity (sp).

When a string that has been at rest for a given time, say 12 hours is plucked hard, does it draw up for a certain period of time, in a very small incriment of a hz?

These are not trick questions, I just wondered if you have the equipment, and/or the time to put this into documented form.

Thanks for any answer.

EJL

Jim Cohen · From: Philadelphia, PA

Strings can be 'vindictive'??

Eric West · From: Portland, Oregon, USA, R.I.P.

Well they can certainly be pissy...

Can I say that?

EJL

Brett Anderson · From: Arizona, USA

Pissnickety!!!!

ed packard · From: Show Low AZ

EJL...Re the graphic presentation of the Hz vs. time after picking...if Peterson would bring out, or internally capture the "error voltage" that causes their disc to rotate as a function of off pitch, this could be done. It would be nice to have the signal amplitude captured at the same time so that off pitch as a function of picking aggressiveness would be part of the presentation.

Other than that, setting up a stable function generator to beat with the strings signal, and capturing and interpreting the beats would work

Re the second question: Playing vibration, as well as hand/stage heat will cause the string to lengthen a bit. The instrument body will also grow thus tensioning the string...hopefully these are a wash, or at least very small. There will be a time lag because of string/body mass differential and thermal conductivity differences between materials.

Letting the instrument sit around for "12 hrs" would change the strings pitch according to the environment change, and everything would "settle in/stabilize". Things would change again when the fingers were applied to the instrument. The changes would again be time, environment and activity dependent. It is hard to get a stably reference.

Say that the instrument was on a stand (standard guitar/bass), or the steel was let stand without a cover, and the fingers/body were not allowed to touch the strings: Then the pitch change as a function of vibration could be tracked per the methods given for your first question.

We should get on Peterson re an error voltage re cents off-pitch.

Bobby Lee · From: Cloverdale, California, USA

Why not use a wave frequency counter instead of a musical tuner? Just curious...

Eric West · From: Portland, Oregon, USA, R.I.P.

Ed.

I'm not aware that there is a disc involved in the new Tuners. I thought they were only digital representations not susceptable to Inertia. I suppose it could be programmed in..

( In other words, when a string is attacked, it sways, increasing tension immediately and then lessening the "sway" as is decays.)

My simple Boss TU15 shows a fluctuation apon attack, but no timeline.

The second "Vindictiveness" question is asked independent of temperature, and the rest period of say 12 hours is to let the string assume it's unmolested molecular properties. When picked, it would not be touched or in any kind of temperature change as having warm hands laid on it. It is just picked, and recorded for a period of a minute or two as to whether it "draws up" higher than it was when at rest for 12 hours. I would think that a string that is more slack than usual would accentuate any change.

This property of "vindiction" would be likened to a piece of hot metal being quuenched rapidly and mis shaping, as opposed to cooling slowly and returning to shape uniformly.

Anyhow, I always enjoy your findings.

b0b.
I think that's what a tuner is.

EJL

BTW, WRT Sierra. I was around here during their whole lifespan. I played and tried many of their guitars. Many of the early ones had trouble staying in tune, returning properly and had other design glitches.

The first owner had a reputation for minimalizing input from the people he had working there, or artists that tried his rigs. Aside from being a good person and a first class hydro.. hydra... hid.. well, you know, a machinist.

Tom Baker, was THE best part of the "old company" and definitely the GEM of the New One.

Ron ! · Posted 3 Jul 2006 10:08 am

ed packard · From: Show Low AZ

I don't have one...they cost too much, and the error voltage vs cents off would still have to be created and recorded as the problem requires capturing freq vs time. Via a data logging interface, the direct freq vs time could be captured, but that is an added expense.

The Peterson already has an internal source of the equivalent of error voltage to make their disk rotate as a function of cents off, and they have a software unit that would save the problem of an external data logger interface.

Eric West · From: Portland, Oregon, USA, R.I.P.

Ed. Is there a disk that rotates in these new Peterson E-tuners??

I thought it was a digital representation.

?

EJL

Dean Parks · From: Sherman Oaks, California, USA

Two things

1. A traditional strobe tuner with a disk works like this, as I understand it:

The disk spins at a constant rate. The fine tuning of that rate is handled by a calibration knob on the front.

The checkerboard pattern around the edge is backlit by a bulb which pulses bright with each cycle of the tone coming into the input, and if the tone is in tune with the calibration tone, the pulses are in sync with the 'windows' of tranparency as the disc turns, and the pattern appears to hold still. Slightly sharp appears to move slightly clockwise, etc.

So "errors" in the pitch at the input change the frequency of the light, not the rotation of the disk.

The new virtual stobes use the same idea (disc is replaced by a software clock that does the disk part... the incoming pitch still does the second part, and the graphic simulates the difference between the two as it would have appeared with a disc.)

2. With a computer audio sequencer, you can use an "autotune" plugin to view a recording's pitch in comparison to an in-tune centerline. Do a screenshot of the pitch-edit window to save and/or print the results for comparison. The sequencers usually give you a choice of timeline for viewing: SPMTE is a clock format but not necessarily detailed enough for this; you could use bars-and-beats as a way also (1/4 bars at 60 bpm= 1 second per bar. Each bar [second] is numbered)

ed packard · From: Show Low AZ

EJL....no physical disk/disc in the Peterson virtual tuners...software equiv for the same type of presentation...refer to Dean's answer.

Dean...thanks for the input...might be made to do the job.

Eric West · From: Portland, Oregon, USA, R.I.P.

I know that..

I was just wondering about the spike in the hz of a plucked string, and a graphic representation of it.

And a measuring if any of a "vindictive" drawing up of a string at rest for a period after being plucked.

Let me know if it's measureable.

I'll try some basic tests with my BossTU15 as I get time this 4th.

EJL

ed packard · From: Show Low AZ

Mr. West, Sir!

I suspect that measurement is possible...Tuner would need mod help by the maker. Other approaches would be too pricey in equipment for me.

I sure would like data logging capability, triggering and time to/of sample, with the Peterson.

Joseph Meditz · From: Sierra Vista, AZ

Hi Eric,

I have done this for a 6 string by recording the string to a .wav file and analyzing it off-line. I've taken the liberty of sending you and Ed the .jpg (33k)of the delta Hz vs. time for the 5th string, A-110, over an 8 second interval.

You'll see that the string is about 1/4 Hz sharp. That is the result of tuning by ear to an A-440 tuning fork which I later measured and found to be a fraction of a Hz sharp.

Joe

ed packard · From: Show Low AZ

Good stuff Joe...Thanks for the data and the data and the "How to".

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