Body wood affects tone

WezV

MartinB said:

crunchman said:

I think @Three-ColourSunburst does have a point about the use of the word resonant.  I think the something like "responsive" would be better for what a lot of people on guitar forums use the word resonant for.  When people talk about a guitar with a "resonant" body they aren't talking about the resonant frequency, they are talking about something that feels and sounds responsive, for want of a better word. 

While he is right on that, he is still completely wrong his assertion that there is a neglible effect on string vibration because of the body.

What @Gassage has done shows that strings do vibrate with an audible signal when excited by body wood.

The Bernie Marsden video spectacularly showed the sound from the 12 string pickups on the double neck when he played the 6 string neck.  By far the most likely mechanism for that is vibrations transmitted through the body.  If someone has one of those double necks, that could easily be proved by doing the same thing with the 6 string pickups turned down.

Yes, what I read from the available information is that the body can and does have some effect on the vibration of the string and consequently on the sound produced, but under the the conditions examined in the studies (and many playing and listening situations) the effect may be too small for this to be significant.  There simply is not enough information in any of the studies to say that this could never be of a large enough extent to be significant under all instrument designs, playing methods or measurement/listening conditions though. 
Mr Sunburst wants an absolute yes/no answer, and is more than happy to cherrypick and misinterpret data to provide him with the answer he decided he wanted from the beginning.  That's neither scientific nor objective, it's an ego-driven pissing contest.  I have availed myself of the ignore function, as there is nothing to be gained from "debate" with someone like that. 

good post - bears repeating.  I have also used the ignore function for this reason.  I am still in the discussion for those who are making good points on both sides of the argument

I have tried a couple of times to mention pickup vibration...this was totally misconstrued as a misunderstanding of how pickups work ("you are thinking of piezo pickups" - no I am not).  it also led to talk of microphonics, which also wasn't quite my point but I do think its valid.

I don't think this is the most important variable, but I do think its often overlooked so I am going to try and explain it again - forget about  microphonics for the time being please.

In this picture, imagine the string is vibrating and the pickup is still.  You have a ferrous metal (the string) vibrating within a still magnetic field.  we all know this produces a strong signal

Now imagine the opposite - the pickup is moving and the string is still.  This time you have  a still ferrous metal (the string)  within a vibrating magnetic field.  I believe this still creates a signal.  obviously it will be much weaker on a guitar because a pickup does not vibrate as much as a string, but it does vibrate. 

 I imagine if you made the movement of the magnetic field match the movement of the string in the first example, you would get an equivalent signal.

The truth is neither description is accurate  or that useful because you actually have a ferrous metal vibrating within a vibrating magnetic field.   Both are moving - neither is totally isolated from the other

Whether this happens is undeniable,  but I admit its affect is up for debate and I don't have proof its something you can hear.  I would be happy for someone with a better understanding of magnetic inductance to explain why the second example can't possibly create a signal.

Sadly this also makes it much harder to test if I am right.   The tuning fork test is introducing vibration to the pickup and the string at the same time.  You would need to find a way to isolate the separate components more effectively than you can do on a real guitar.

Its the best argument for the noticeable differences you get between direct and ring mounted pickups.  Obviously this links to the importance of body structure without focusing on which woods do what,  and other assorted guitar shop mythology.

Microphonics can be reintroduced to that basic model in bold above.  Not sure this is quite the correct wording, just a go   A ferrous metal vibrating within a vibrating magnetic field which varies based on the internal vibration of the pickup itself.

I said previously I think you can understand an electric guitar sound purely as a relationship between string and pickup.... but I don't think for one second that relationship is as simple as some people want to believe.  

Roland

crunchman said:

What @Gassage has done shows that strings do vibrate with an audible signal when excited by body wood.

The classic example of this is the 1960s trick of touching the headstock or body of the guitar to the speaker cabinet. Before 50w and 100w amps it could sometimes be difficult to get feedback. If the volume of sound coming out of the speaker wasn't sufficient then vibrating the wood would.

NelsonP

Three-ColourSunburst said:

Body Woods and an Electric Guitar’s Frequency Spectrum

Keith J. Soper

University of Toledo

ABSTRACT

There are many theories as to what significance particular wood species contribute if any to the overall tone of an electric guitar. In this paper two differing wood types are studied, ash and alder, and a method are investigated to determine their tonal spectrums. Analysis of the data shows that in an electric guitar the body wood type does not contribute significantly to the sound of the amplified instrument.

http://www.stormriders.com/guitar/telecaster/guitar_wood.pdf

There's something bothering me about this study and it's this:

The conclusions from the study were done based on a 'A qualitative review of the signal waveforms'. Basically this means eyeballing the the frequency response graphs.

Let's look at that in more detail. If you look on page 4/5 you will see the frequency response curves. At first glance the ones generated by the pickups do look similar. But in some cases there are >10db differences at certain frequencies between the Alder and Ash bodies e.g. D string w pickup @ around 6.5kHz.

If you compare that to the frequency response of, say a Vintage 30 vs a G12T75 then you can see that quite possibly the wood that the guitar is made from does make an audible difference to the tone.

No?

NelsonP

Duplicated post - mods please remove

Not you Weller

NelsonP

Duplicated post - mods please remove

Ravenous

NelsonP said:

Now compare those differences to those observed by Keith Soper (see P 4 of the linked doc). Even to my untrained eye those difference look bigger.

Yes looking at the past posts I thought the same, when 3SC found that document. (Tuesday before last, I think.  So much time we've wasted on this!)

There were very definite differences in the graphs - visible several seconds after the peak of the note, and I have no idea if the differences would be audible, but it seemed a reasonable student project to set up the measuring systems, show some graphs and comment on them.  NOT rigorous research, we shouldn't expect it from someone at that stage in their training.

(It was when I read this document I first realised the poster who found it really had no clue what the subject is about...)

MartinB

NelsonP, that's a good point.  I have a bit of a scientific background (in a field completely unrelated to this), and for a paper to declare that something is significant or not without having first clearly defined how they are determining significance is a major red flag in any field.   I'd be very cautious about the findings of any paper that does this.  

Cirrus

@NelsonP yes, absolutely. I thought the same thing. And I think, buried somewhere in these pages of response, @ICBM  actually said as much as well - there *are* differences in the pickup response, and they are at certain frequencies significant.

The other element to it is one I tried to introduce but I think it got lost in the noise - transient response. At the attack of a guitar note there's a big energy spike - the sustain is much softer. So I'd be interested to see a waterfall graph showing the frequency response over time - how the transient attack unfolds has a big influence on how we perceive a sound. Everyone's talking about a sustaining string in isolation and how the vibrations transfer through the body, but I think it's in the transients, those brief few milliseconds at the start of a note, when you get your hands on the guitar and dig in, that reveal the character of an instrument. That's where guitars are snappy, or thick, or quick, or fat - how they handle that initial percussive attack.

crunchman

Cirrus said:

The other element to it is one I tried to introduce but I think it got lost in the noise - transient response. At the attack of a guitar note there's a big energy spike - the sustain is much softer. So I'd be interested to see a waterfall graph showing the frequency response over time - how the transient attack unfolds has a big influence on how we perceive a sound. Everyone's talking about a sustaining string in isolation and how the vibrations transfer through the body, but I think it's in the transients, those brief few milliseconds at the start of a note, when you get your hands on the guitar and dig in, that reveal the character of an instrument. That's where guitars are snappy, or thick, or quick, or fat - how they handle that initial percussive attack.

I think you are right about this.

Again, a lot of that will be down to construction.  An ash bodied Strat with a trem and the springs probably has a lot less immediate attack than an ash bodied Tele.

[Thinking about this, a lot of the Tele sound is down to the way the pickup is mounted in the metal bridge plate.  The fact that what the pickup is mounted in makes such a difference to the sound is quite informative in itself.]

NelsonP

Cirrus said:

The other element to it is one I tried to introduce but I think it got lost in the noise - transient response.

Yes, absolutely. I'd seen that and tried to revive the idea a few posts back. But there is a lot of noise!

Also, we've talked a lot about resonance of certain frequencies but not enough about damping of others. Presumably that would have an impact too?

The other point that may have got lost is that the perceived tone or a guitar may also be influenced by other senses - i.e. touch. Since you feel the vibration of the instrument via the body and neck then, perhaps this plays a part in our perception of 'tone'?

OilCityPickups

WezV said:

MartinB said:

crunchman said:

I think @Three-ColourSunburst does have a point about the use of the word resonant.  I think the something like "responsive" would be better for what a lot of people on guitar forums use the word resonant for.  When people talk about a guitar with a "resonant" body they aren't talking about the resonant frequency, they are talking about something that feels and sounds responsive, for want of a better word. 

While he is right on that, he is still completely wrong his assertion that there is a neglible effect on string vibration because of the body.

What @Gassage has done shows that strings do vibrate with an audible signal when excited by body wood.

The Bernie Marsden video spectacularly showed the sound from the 12 string pickups on the double neck when he played the 6 string neck.  By far the most likely mechanism for that is vibrations transmitted through the body.  If someone has one of those double necks, that could easily be proved by doing the same thing with the 6 string pickups turned down.

Yes, what I read from the available information is that the body can and does have some effect on the vibration of the string and consequently on the sound produced, but under the the conditions examined in the studies (and many playing and listening situations) the effect may be too small for this to be significant.  There simply is not enough information in any of the studies to say that this could never be of a large enough extent to be significant under all instrument designs, playing methods or measurement/listening conditions though. 
Mr Sunburst wants an absolute yes/no answer, and is more than happy to cherrypick and misinterpret data to provide him with the answer he decided he wanted from the beginning.  That's neither scientific nor objective, it's an ego-driven pissing contest.  I have availed myself of the ignore function, as there is nothing to be gained from "debate" with someone like that. 

good post - bears repeating.  I have also used the ignore function for this reason.  I am still in the discussion for those who are making good points on both sides of the argument

I have tried a couple of times to mention pickup vibration...this was totally misconstrued as a misunderstanding of how pickups work ("you are thinking of piezo pickups" - no I am not).  it also led to talk of microphonics, which also wasn't quite my point but I do think its valid.

I don't think this is the most important variable, but I do think its often overlooked so I am going to try and explain it again - forget about  microphonics for the time being please.

In this picture, imagine the string is vibrating and the pickup is still.  You have a ferrous metal (the string) vibrating within a still magnetic field.  we all know this produces a strong signal

Now imagine the opposite - the pickup is moving and the string is still.  This time you have  a still ferrous metal (the string)  within a vibrating magnetic field.  I believe this still creates a signal.  obviously it will be much weaker on a guitar because a pickup does not vibrate as much as a string, but it does vibrate. 

 I imagine if you made the movement of the magnetic field match the movement of the string in the first example, you would get an equivalent signal.

The truth is neither description is accurate  or that useful because you actually have a ferrous metal vibrating within a vibrating magnetic field.   Both are moving - neither is totally isolated from the other

Whether this happens is undeniable,  but I admit its affect is up for debate and I don't have proof its something you can hear.  I would be happy for someone with a better understanding of magnetic inductance to explain why the second example can't possibly create a signal.

Sadly this also makes it much harder to test if I am right.   The tuning fork test is introducing vibration to the pickup and the string at the same time.  You would need to find a way to isolate the separate components more effectively than you can do on a real guitar.

Its the best argument for the noticeable differences you get between direct and ring mounted pickups.  Obviously this links to the importance of body structure without focusing on which woods do what,  and other assorted guitar shop mythology.

Microphonics can be reintroduced to that basic model in bold above.  Not sure this is quite the correct wording, just a go   A ferrous metal vibrating within a vibrating magnetic field which varies based on the internal vibration of the pickup itself.

I said previously I think you can understand an electric guitar sound purely as a relationship between string and pickup.... but I don't think for one second that relationship is as simple as some people want to believe.  

Good post too @WezV which is bang on the nail ... have a wizdom

crunchman

Three-ColourSunburst said:

I also think that Marsden's guitar has been modified to turn the 6 and 12-string pickups together

Before I suggested the experiment above, I looked for a wiring diagram on these to make sure it was feasible.  I think that you can have either or both on at the same time.  I don't think that is a modification.

Sassafras

Gassage said:

Rabs said:

Well while we are at it. This is one of the more interesting alternative guitars ive seen.

That guy seems quite potty.

I'm embarrassed at how long it took me to get that.

Roland

Cirrus said:

The other element to it is one I tried to introduce but I think it got lost in the noise - transient response. At the attack of a guitar note there's a big energy spike - the sustain is much softer. So I'd be interested to see a waterfall graph showing the frequency response over time - how the transient attack unfolds has a big influence on how we perceive a sound. Everyone's talking about a sustaining string in isolation and how the vibrations transfer through the body, but I think it's in the transients, those brief few milliseconds at the start of a note, when you get your hands on the guitar and dig in, that reveal the character of an instrument. That's where guitars are snappy, or thick, or quick, or fat - how they handle that initial percussive attack.

It surprises me how many times people look at the steady state, because it's easier to picture and measure, rather than the transient, where most of the interest is.

Cirrus

Roland said:

It surprises me how many times people look at the steady state, because it's easier to picture and measure, rather than the transient, where most of the interest is.

It's just occurred to me - this idea of knocking pieces of wood and hearing a difference... well, what's that knock? A transient. And the sound of the wood when you knock it is, if you like, the impulse response.

Ravenous

Roland said:

It surprises me how many times people look at the steady state, because it's easier to picture and measure, rather than the transient, where most of the interest is.

Cirrus said:

It's just occurred to me - this idea of knocking pieces of wood and hearing a difference... well, what's that knock? A transient. And the sound of the wood when you knock it is, if you like, the impulse response.

Well yes it's the frequency response we're after.  In the steady state a piece of wood doesn't move (provided it's bearing whatever load is on it - back to the old rubber bridges argument of around 15-20 pages ago.)

Mechanical impedance (mentioned earlier) is frequency dependent too of course.  Unfortunately all this stuff requires fairly hard calculus to model, as well as good data on the response of the materials...

koneguitarist

So after all the various replies I think the main findings in my view is as follows. 
1: Does tonewood make a difference to the overall sound of a electric guitar? Possibly not in a significant way. But like all components of the instrument will add or subtract to the tone. 

2: Does the design and execution of guitar neck to body matter? I think yes mainly to the resonance not tone. 

3: species or grain/tightness of wood which makes the most difference? Again I think tightness and grain more so than species of wood. This is borne out by tele's or strats made from so many different species of wood still sounding like what they are, tele or strat! 

@Three-ColourSunburst  are you happy with what you have found out over last 20 odd pages? 

GSPBASSES

Cirrus said:

Roland said:

It surprises me how many times people look at the steady state, because it's easier to picture and measure, rather than the transient, where most of the interest is.

It's just occurred to me - this idea of knocking pieces of wood and hearing a difference... well, what's that knock? A transient. And the sound of the wood when you knock it is, if you like, the impulse response.

Interesting you mention knocking a piece of wood, Knocking, tapping or flicking a piece of wood is one of the main ways I check out some woods before purchasing, like ebony fingerboard's, blocks of mahogany, or if I'm buying soundboards that are going to be used on semi-hollow guitars. I would say the initial tap and ring of a piece of wood will tell me if it's going to make a good sounding guitar. I know this several acoustic builders on the forum who I'm sure also use the tap or flick on soundboards and backs, when selecting the ones that sound best. Not very scientific I know, but that's how I've been choosing my wood for years. When I'm at David Dykes there is nearly always an acoustic guitar, violin or cello builder there, you can guarantee that they will all tap every piece of wood before it is purchased. Perhaps one of the acoustic builders on the forum might expand on this, as I'm sure what I'm looking for is slightly different.

As far as I'm concerned tone woods do make a difference to the sound of the guitar. However, there is a point when it does not.  I will explain more on this in another post, as I feel this post is now going round in ever decreasing circles and will soon disappear up its own arse with any luck.

koneguitarist

@GSPBASSES ;Personally myself I think the best and easiest way to dispel the myth of tonewood, both for builders and customers is to build a guitar to your usual high standards of UK wood such as Oak, Beech or Sycamore maybe use and a RockLite fretboard (man made ebony equivalent) and listen to the results. 
If the difference in tone is as negligible as the difference between another two of your guitars made the same way but with your usual choice of woods, then that would prove that as long as guitar is made well with decent wood, so called tone wood would be proven in most ears to be what it is a myth. 

octatonic