"Henry Kolesnik" wrote in
message
. net
There's a good example of a 3D plot he
http://www.spectraplus.com/screenshots.html#3d
Has anyone used this software?

Yes, but not for exactly that purpose.

Here's a sample of my usage of Spectra:

http://www.pcavtech.com/soundcards/lynxtwo/

On Mon, 19 Feb 2007 15:16:29 -0600, "Henry Kolesnik"
wrote:

There's a good example of a 3D plot he
http://www.spectraplus.com/screenshots.html#3d
Has anyone used this software?

Hi Hank,

Yes, I have. It is exceedingly expensive, but you can probably get 30
days of free use if you have a one-time knock off project. Of course,
it may take 30 days to figure it out.

FFT analyzers are a dime a dozen, but few know how to use them
accurately - or are even aware of what can be done with them. Bob's
complaint, notwithstanding, a 1024 bin FFT employing the proper mixing
inputs can resolve any note on a guitar to within hundredths of a
cycle. I am sure this is of no interest to you, however.

What are you trying to measure? The dime a dozen analyzers (meaning
free, or packaged with other software) can do enough if you are not
particularly demanding.

73's
Richard Clark, KB7QHC

"Richard Clark" wrote in message

On Mon, 19 Feb 2007 15:16:29 -0600, "Henry Kolesnik"
wrote:

There's a good example of a 3D plot he
http://www.spectraplus.com/screenshots.html#3d
Has anyone used this software?

Hi Hank,

Yes, I have. It is exceedingly expensive, but you can
probably get 30 days of free use if you have a one-time
knock off project. Of course, it may take 30 days to
figure it out.

FFT analyzers are a dime a dozen, but few know how to use
them accurately - or are even aware of what can be done
with them. Bob's complaint, notwithstanding, a 1024 bin
FFT employing the proper mixing inputs can resolve any
note on a guitar to within hundredths of a cycle. I am
sure this is of no interest to you, however.

Over the years, the most useful FFT software I've had, is the (fairly
simple) FFT analyzer in Audition/CEP. It's big plus is the ability to use
the Audition/CEP audio editor to select portions of real-world waveforms,
and to use the wave generation and modification features to create waves for
use in analysis and testing.

On Mon, 19 Feb 2007 17:23:32 -0500, "Arny Krueger"
wrote:

Over the years, the most useful FFT software I've had, is the (fairly
simple) FFT analyzer in Audition/CEP. It's big plus is the ability to use
the Audition/CEP audio editor to select portions of real-world waveforms,
and to use the wave generation and modification features to create waves for
use in analysis and testing.

Hi Arny,

I am sure this is an useful tool, but without windowing the data, any
semblance to reasonable analysis is a house built on sand. I note in
your provided link to work you have done that you use Blackman
exclusively. This is at least a good first pass to achieving an
analysis, but any variety of work is going to be more demanding (the
Blackman window has its limitations), otherwise it is like looking
through glasses smeared with Vaseline.

73's
Richard Clark, KB7QHC

Amy, Bob, Richard
Thanks for your response and interest. I'm retired used to be an
engineer
before management laid waste to that. I've started taking weekly guitar
lessons over a year ago and slowly getting a bit better. It's a hell
of a challenge at 66. I want
to buy a better guitar and all guitars don't sound the same, even the
same model. One shouldn't expect them to because they're all made from
different cuts of wood and assembled by human hands. What amazed me is
that the materials used for the nut, neck, saddle and bridge as well as
the mfg and age of the strings have a noticeable effect on the sound.
The bridge pins, angle of the strings out of the bridge pin holes and
tuners also have effects.
In the last year I found at least four guitars that I really liked, 3
used ones and a new one all over a $1000.00 but I passed because I'm not
that impulsive or flush with cash. A good player can make just about
any guitar sound good, or a hell of a lot better than me.
I'm into ham radio also and last year at hamfest I traded for an HP
3582A spectrum analyzer but the learning curve is a bit steep for me.
So unless I can find an experienced user or devote much more time to it
I'm going to have to trade it.
Last week I won an HP 3561A on ePay but it has a problem that I hope I
can fix. In the meantime I thought it might make sense to scope out
sound cards and related software. I know a lot of hams use sound cards
for various & different applications and it's about time I took a wack
at one and what better way than trying to figure out what it is that
makes one guitar sound so much better than another. Or if changing the
nut, saddle or bridge pins really improves the sound or is it just
wishful thinking.
And I can make use of it for ham radio weak signal detection and
analysis.
I used a term; slab diagrams which may be known as stack diagrams. I'm
interested in watching a plucked and later chords as they decay over
time in sort of a 3D plot. There's a good example of what I'm looking
for in the HP catalog describing the HP 3561A.
tnx

73
Hank WD5JFR

"Richard Clark" wrote in message
...
On Mon, 19 Feb 2007 15:16:29 -0600, "Henry Kolesnik"
wrote:

There's a good example of a 3D plot he
http://www.spectraplus.com/screenshots.html#3d
Has anyone used this software?

Hi Hank,

Yes, I have. It is exceedingly expensive, but you can probably get 30
days of free use if you have a one-time knock off project. Of course,
it may take 30 days to figure it out.

FFT analyzers are a dime a dozen, but few know how to use them
accurately - or are even aware of what can be done with them. Bob's
complaint, notwithstanding, a 1024 bin FFT employing the proper mixing
inputs can resolve any note on a guitar to within hundredths of a
cycle. I am sure this is of no interest to you, however.

What are you trying to measure? The dime a dozen analyzers (meaning
free, or packaged with other software) can do enough if you are not
particularly demanding.

73's
Richard Clark, KB7QHC

In article ,
"Henry Kolesnik" wrote:

Amy, Bob, Richard
Thanks for your response and interest. I'm retired used to be an
engineer
before management laid waste to that. I've started taking weekly guitar
lessons over a year ago and slowly getting a bit better. It's a hell
of a challenge at 66. I want
to buy a better guitar and all guitars don't sound the same, even the
same model. One shouldn't expect them to because they're all made from
different cuts of wood and assembled by human hands. What amazed me is
that the materials used for the nut, neck, saddle and bridge as well as
the mfg and age of the strings have a noticeable effect on the sound.
The bridge pins, angle of the strings out of the bridge pin holes and
tuners also have effects.
In the last year I found at least four guitars that I really liked, 3
used ones and a new one all over a $1000.00 but I passed because I'm not
that impulsive or flush with cash. A good player can make just about
any guitar sound good, or a hell of a lot better than me.
I'm into ham radio also and last year at hamfest I traded for an HP
3582A spectrum analyzer but the learning curve is a bit steep for me.
So unless I can find an experienced user or devote much more time to it
I'm going to have to trade it.
Last week I won an HP 3561A on ePay but it has a problem that I hope I
can fix. In the meantime I thought it might make sense to scope out
sound cards and related software. I know a lot of hams use sound cards
for various & different applications and it's about time I took a wack
at one and what better way than trying to figure out what it is that
makes one guitar sound so much better than another. Or if changing the
nut, saddle or bridge pins really improves the sound or is it just
wishful thinking.

What a neat project!

I can tell you, based on years of experience with changing out the parts
that you mentioned (nut, saddle, bridge, pins, ESPECIALLY break angle)
that these things DO make a difference in the sound. I have NOT heard a
difference with changes of neck or tuners (certainly these things affect
the intonation of the instrument, but I've never known then to change
the quality of sound).

However, the choice of wood, body shape, and top bracing are far more
relevant. You might want to check with Martin, Taylor, Larrivee, et al
to see if they have any scientific info that can help you. They aren't
in the business of pushing pins, tuners, etc.

Good luck and please post what you find out!

(Since this is RAO, I should point out that my hearing of the things
mentioned in my second paragraph above is based on differences heard
based on changes made to the instruments when it wasn't possible to know
about the changes.)

Jenn
The neck wood affects the sound energy as it goes from the nut vibrate
the guitar and so does the truss rod. Tuners can influence the sound
because their weight can dampen vibrations. An interesting thing is to
hold a tuner lightly ( or the headstock) when
you pluck a string and feel the vibrations.
A good analysis should be able to detect loose bracing and you should
also be able to see the effects of scalloped bracing.
I shotgunned this query because I didn't know where I would find the
most help. If responders can suggest a group I could limit it and not
waste time of those who aren't interested.
I've also made unconnected posts to other groups, but have less interest
and reponse so far.
I didn't post to any guitar groups because most there are musicians that
don't need this kind of crutch and have an ear that's been trained for
many years. I want to see if I can catch up by being able to see.
In addition it should be helpful in voice training which I also need
because I'm trying but with less success to sing.

73
Hank WD5JFR

"Jenn" wrote in message
...
In article ,
"Henry Kolesnik" wrote:

Amy, Bob, Richard
Thanks for your response and interest. I'm retired used to be an
engineer
before management laid waste to that. I've started taking weekly
guitar
lessons over a year ago and slowly getting a bit better. It's a
hell
of a challenge at 66. I want
to buy a better guitar and all guitars don't sound the same, even the
same model. One shouldn't expect them to because they're all made
from
different cuts of wood and assembled by human hands. What amazed me
is
that the materials used for the nut, neck, saddle and bridge as well
as
the mfg and age of the strings have a noticeable effect on the sound.
The bridge pins, angle of the strings out of the bridge pin holes and
tuners also have effects.
In the last year I found at least four guitars that I really liked, 3
used ones and a new one all over a $1000.00 but I passed because I'm
not
that impulsive or flush with cash. A good player can make just about
any guitar sound good, or a hell of a lot better than me.
I'm into ham radio also and last year at hamfest I traded for an HP
3582A spectrum analyzer but the learning curve is a bit steep for me.
So unless I can find an experienced user or devote much more time to
it
I'm going to have to trade it.
Last week I won an HP 3561A on ePay but it has a problem that I hope
I
can fix. In the meantime I thought it might make sense to scope out
sound cards and related software. I know a lot of hams use sound
cards
for various & different applications and it's about time I took a
wack
at one and what better way than trying to figure out what it is that
makes one guitar sound so much better than another. Or if changing
the
nut, saddle or bridge pins really improves the sound or is it just
wishful thinking.

What a neat project!

I can tell you, based on years of experience with changing out the
parts
that you mentioned (nut, saddle, bridge, pins, ESPECIALLY break angle)
that these things DO make a difference in the sound. I have NOT heard
a
difference with changes of neck or tuners (certainly these things
affect
the intonation of the instrument, but I've never known then to change
the quality of sound).

However, the choice of wood, body shape, and top bracing are far more
relevant. You might want to check with Martin, Taylor, Larrivee, et
al
to see if they have any scientific info that can help you. They
aren't
in the business of pushing pins, tuners, etc.

Good luck and please post what you find out!

(Since this is RAO, I should point out that my hearing of the things
mentioned in my second paragraph above is based on differences heard
based on changes made to the instruments when it wasn't possible to
know
about the changes.)

On Tue, 20 Feb 2007 05:27:17 GMT, Jenn
wrote:


(Since this is RAO, I should point out that my hearing of the things
mentioned in my second paragraph above is based on differences heard
based on changes made to the instruments when it wasn't possible to know
about the changes.)

Eh?

On Mon, 19 Feb 2007 10:34:50 -0800, Richard Clark
wrote:

On Mon, 19 Feb 2007 14:06:30 GMT, (Bob Masta)
wrote:

FFT size is 1024 points, so you won't be able to use
this for tuning your guitar, if that's what you had in mind.

Hi Bob,

Why not? 1024 points (bins) has enough resolution to shake out every
note on a Hawaiian slide guitar. The only care is selecting the
sampling rate and most FFT packages should be able to resolve
exceedingly fine.


The problem is that the line resolution of an FFT is the sample
rate divided by the number of time points. So with 44100 Hz
sample rate and 1024 points you get a bit over 43 Hz per line.
So the first non-DC spectral line would be 43 Hz, which is about
a low F on a bass guitar, and the very next line would be the F
an octave above that... you'd miss an entire octave!

The standard musical note frequencies (semitones) differ
from each other by about 6% (12th root of 2, since there are
12 notes in an "octave"). But you need much better
resolution than this for tuning, typically a "cent" or so,
namely 1/100 of a semitone or .06%. At 43 Hz that
works out to about 0.026 Hz. A 64K-point FFT
at 44100 Hz will have a native resolution of 0.67 Hz,
which still isn't good enough... but at 64K samples,
you are looking at 1.48 seconds of sound. If the
pitch changes over that interval, the spectral peak
will be smeared even further.

If you attempt to beat this game by going to lower
sample rates, note that frequency resolution is
still proportional to the inverse of the total sampling
interval. So if you tried to use the 1K FFT but sample at
44100 / 64 = 689 Hz to get the same (inadequate)
resolution as the above 64K FFT, you'd still need 1.48
seconds of sound. Sound cards don't sample that
low intrinsically (typically 8K lower limit, 4K on old
Sound Blasters), but you might manage using sample
rate conversion (either Windows or sound card built-in).
I haven't tried this, but I suspect that it would not be a satisfying
experience due to the s-l-o-w time response.

Best regards,





Bob Masta

D A Q A R T A
Data AcQuisition And Real-Time Analysis
www.daqarta.com
Scope, Spectrum, Spectrogram, Signal Generator
Science with your sound card!

On Mon, 19 Feb 2007 14:08:54 -0800, Richard Clark
wrote:

On Mon, 19 Feb 2007 15:16:29 -0600, "Henry Kolesnik"
wrote:

There's a good example of a 3D plot he
http://www.spectraplus.com/screenshots.html#3d
Has anyone used this software?

Hi Hank,

Yes, I have. It is exceedingly expensive, but you can probably get 30
days of free use if you have a one-time knock off project. Of course,
it may take 30 days to figure it out.

FFT analyzers are a dime a dozen, but few know how to use them
accurately - or are even aware of what can be done with them. Bob's
complaint, notwithstanding, a 1024 bin FFT employing the proper mixing
inputs can resolve any note on a guitar to within hundredths of a
cycle. I am sure this is of no interest to you, however.

Yes, you can easily resolve to 100ths of a cycle, but not from
a native FFT. (See my other response.) You can do it from
the waveform by measuring the time between cycles. That's
one of the methods I'm working on. The other is to do it from
the FFT via peak interpolation. The waveform method will
be very accurate with simple static waveforms, but I expect it
will have trouble with the 2nd harmonic of a plucked string,
which is not an integer multiple so "rolls" through the waveform.
The FFT interpolator will not have the same raw accuracy, and must
have absolutely separated spectral peaks since it assumes the
one it's interpolating is the only one. I'm not hopeful it can be
made good enough to tune a guitar, at least not in the bottom
octave where the harmonics land on adjacent spectral lines.

Best regards,


Bob Masta

D A Q A R T A
Data AcQuisition And Real-Time Analysis
www.daqarta.com
Scope, Spectrum, Spectrogram, Signal Generator
Science with your sound card!