Guitar Cables

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muttley600 said:
I remember all those claims. Wow that goes back. Weren't there also claims that people were hearing stereo from MW/LW mono broadcasts? And bangs and crashes in the back seat sort of stuff? They never did get to the bottom of that one.:D
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Seriously though, this is something I've always wondered about but never bothered to research. How are we able to hear bass tones with headphones? Is it the same type of deal or something else?
 
famous beagle said:
Oh wow, ok we should just stop there ... don't even get me started on psychology compared to medicine! I truly believe that the mind could take care of just about any malady if we were able to use it properly. Self-anesthetizing (which has been widely documented) is only the tip of the iceberg with regards to mind over matter.
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True again to a point the mind is a wondrous thing. But if I'm in a car wreck I want a Doctor of medicine not psychology. No amount of thinking is gointo grow my body parts back..;)

I do take your points on board though. There are some fascinating examples of psycho-acoustic behavior.
 
famous beagle said:
Self-anesthetizing (which has been widely documented) is only the tip of the iceberg with regards to mind over matter.
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I have some experience with self-anesthesis. A sixpack of Anchor Porter and a few shots of Tullamore Dew usually does the trick.
 
Zaphod B said:
Mutt, please educate me. What are wolf tones and resultants?
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Resultant tones I posted a link to in the previous thread.

A wolf tone can best be described as a single note that sounds way louder than others. They are the curse of the violin world because they can really destroy the balance of a good instrument. You can get them on guitars as well. They are caused by the note being excited at a certain frequency beyond it's expected level. Normally the cause is something like the belly or back, or the chambre having a fundamental frequency on or close to the frequency of the wolf tone. The effect is to couple the two with one driving the other. Kind of like a natural feedback. You ever had a guitar that seems to feedback when the band play a certain note? Thats more or less the same thing.

The cure is to add mass or stiffness to the offending part of the instrument. By doing so you raise or lower the fundamental frequency of that part. Thats why you often see fiddles with little clamps or weights added behind the bridge.

I always make sure when I'm doing the final voicing on acoustic instrument that the tap tone of the top and back don't match and also that they don't fall on a common note in the scale. Even that is no guarantee once it's finished and setup. They are real luthier gremlins at times.:rolleyes:
 
famous beagle said:
Seriously though, this is something I've always wondered about but never bothered to research. How are we able to hear bass tones with headphones? Is it the same type of deal or something else?
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I'm going to take a stab at this with the expectation that someone with better knowledge will correct me.

My understanding is that a good set of headphones actually can be flat down to 20 Hz. When you have them on, or a set of good-quality in-ear monitors, you are bypassing all the normal acoustic minefields associated with a listening room and the headphone driver is more accurately and closely coupled to your eardrum. When you think about how close an in-ear monitor is to your eardrum, it seems to me that it's almost like directly stimulating the eardrum.

That's my guess.
 
famous beagle said:
Seriously though, this is something I've always wondered about but never bothered to research. How are we able to hear bass tones with headphones? Is it the same type of deal or something else?
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I'm not big on room acoustics or monitors etc so that may be a better question for the guys in the other forms. Basically I've always had it down to the fact that my ear is closer to the source and the air is being moved a lot closer to the source than away from it. Sound waves propagate through air at different rates depending on amplitude, frequency and harmonic makeup as well as the type of driver producing the tone.

The answer isn't really in my field. I'd just be giving you an informed guess. Others may be able to flesh out this one but I believe it has more to do with the actual cabinet and driver, headphones can also be viewed as such.
 
Zaphod B said:
I'm going to take a stab at this with the expectation that someone with better knowledge will correct me.

My understanding is that a good set of headphones actually can be flat down to 20 Hz. When you have them on, or a set of good-quality in-ear monitors, you are bypassing all the normal acoustic minefields associated with a listening room and the headphone driver is more accurately and closely coupled to your eardrum. When you think about how close an in-ear monitor is to your eardrum, it seems to me that it's almost like directly stimulating the eardrum.

That's my guess.
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Wow, same conclusion only you said it better.. I bet I'm righter than you tho..:p:D
 
muttley600 said:
Resultant tones I posted a link to in the previous thread.
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Yes, the difference tone is the same as a beat frequency. Beat frequencies is what makes touch tone telephone dialers work. There are seven oscillators, one for each row and one for each column. Each button fires two oscillators which generate a beat frequency unique to that button.
 
ggunn said:
Another one is if you play only the middle 4 strings of a standard 1st position D chord (A D A D) on an acoustic guitar, you'll hear the 9th, an E (the same note as the high open E), even though it's not there. For some reason I don't seem to hear it on my electric guitars, though YMMV.
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Hey, guys, I tried this last night while practicing on the Les Paul through the AC30, and sure enough I observed the same thing.

The first thing I found is that simply strumming those middle 4 notes of a standard D chord (with a pick) stimulated the low E string to resonate at its 12th fret harmonic note. :eek:

Muting both E strings while strumming the middle four strings still resulted in an audible high E although not at the same level as with the E stings unmuted, and not near the same level as the strummed strings.

The effect was more audible with the bridge position than the neck position, but was nevertheless audible through either one.

Mutt, you're the physics guru - do you think this is a resultant occurring?
 
Zaphod B said:
Hey, guys, I tried this last night while practicing on the Les Paul through the AC30, and sure enough I observed the same thing.

The first thing I found is that simply strumming those middle 4 notes of a standard D chord (with a pick) stimulated the low E string to resonate at its 12th fret harmonic note. :eek:

Muting both E strings while strumming the middle four strings still resulted in an audible high E although not at the same level as with the E stings unmuted, and not near the same level as the strummed strings.

The effect was more audible with the bridge position than the neck position, but was nevertheless audible through either one.

Mutt, you're the physics guru - do you think this is a resultant occurring?
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This could be the 7th fret harmonic on the A string coming out maybe?
 
ggunn said:
By the term "resultant", are you referring to beat frequencies?
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Kind of, did you read the link on resultants? My guess is that you have some form of sympathetic vibration going on but it is a guess. Sympathetic vibrations are far more common than resultants or even wolfs. The test for either is to switch frequency. A resultant tone is not frequency dependant. You should hear the same effect at a tone higher or lower if it's a resultant or psycho-acoustic thing. A wolf tone is normally fairly tightly frequency dependant so tuning up or down a tone will move the frequency away from the natural frequency of the body or cavity that sets the wolf up. It would diminish or vanish altogether

I'm not saying that it isn't some kind of psycho-acoustic phenomena just not one I'm familiar with or can reproduce.

Zaphod B said:
Hey, guys, I tried this last night while practicing on the Les Paul through the AC30, and sure enough I observed the same thing.

The first thing I found is that simply strumming those middle 4 notes of a standard D chord (with a pick) stimulated the low E string to resonate at its 12th fret harmonic note. :eek:

Muting both E strings while strumming the middle four strings still resulted in an audible high E although not at the same level as with the E stings unmuted, and not near the same level as the strummed strings.

The effect was more audible with the bridge position than the neck position, but was nevertheless audible through either one.

Mutt, you're the physics guru - do you think this is a resultant occurring?
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See above. Again I doubt it but you could have a sympathetic vibration going on. If this were a common psycho-acoustic thing it would be repeatable on many instruments. Try my suggestions above and let me know what you find. Then we'll look at sympathetic resonances.

I told you lot this stuff isn't easy..;)
 
famous beagle said:
This could be the 7th fret harmonic on the A string coming out maybe?
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Thats were I'm leading and would be an obvious sympathetic vibration or partial harmonic solution. It would also not be frequency dependant so tuning up or down would not effect it. Playing in another key or position possibly would. There are other common sympathetic vibration causes as well.
 
Zaphod B said:
I guess it could be, but why would it be so audible?
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Several reasons. Energy from the string travels around the guitar in complex ways, it could be being driven sympathetically from other string energy at certain frequencies which would emphasise it. Or it could be driven by a natural body resonance in a wolftone style. It is not a true wolf so would be better described as a sympathetic vibration. If it is more apparent when playing the ADAD thing then I suspect it would be the former.

Again, start with the stuff I outlined earlier to try and eliminate a few possibilities, then we can focus on specifics.

EDIT, Just to point out that that harmonic vibration would be going on in any case whenever that open A sounds. What we want to know is why is it so loud in this scenario.
 
What I'll do over the weekend as time allows is this:

-- try it on all my six-string guitars to see if it's common across several instruments - if it is, I think this would indicate that it's not a wolf tone

-- retune one or several, both up and down from concert pitch, to see if it's dependent upon a fundamental tuning pitch, or if the same phenomenon occurs relative to whatever pitch you're tuned to
 
Just to summise all this info to make easier to digest and emphasise why each are distinct I'll outline why each are distinct from the other.

A Resultant tone. A psych-acoustic phenomena that fools the brain into hearing a tone that is not present. They are close to the beat frequencies and normally need a fairly pure tone to be heard. They are NOT frequency dependant.

A Wolf Tone. A tone that is actually present and is emphasised by being excited from a dominant natural frequency of the instrument such as a major part of the body or the air cavity. They ARE frequency deopendant.

A Sympathetic vibration.A vibration of a string or partial harmonic that is present and excited by some specific part of the body that vibrate in sympathy with each other as the name suggests. The difference between that and a wolf tone would be that it is normally only heard in certain positions and IS NOT frequency dependant as the tone causing the sympathetic vibration is related to the frequency in question and would be sounded at the same time. The Harmonic E, 7th fret on the A string in this example is emphasised by the energy from the notes ADAD played in the way they are.

Each of these are very real and can be observed in various musical applications.
 
Zaphod B said:
What I'll do over the weekend as time allows is this:

-- try it on all my six-string guitars to see if it's common across several instruments - if it is, I think this would indicate that it's not a wolf tone

-- retune one or several, both up and down from concert pitch, to see if it's dependent upon a fundamental tuning pitch, or if the same phenomenon occurs relative to whatever pitch you're tuned to
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Hey teach, just because Zaphod's doing homework, that doesn't mean we have to, right?
 
Nice summary, Muttley, thanks.

I'll post the results of my experimentation and let you figure out what's going on. ;)
 
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