False, people are playing their instruments unplugged & feeling the vibration, which they assume is Resonance.
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myth-busting: Resonance is not synonymous with Vibration
- Thread starter Killed_by_Death
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D
Deleted member 165050
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The first sentence has reference to the correct term as used in physics, acoustics, vibration analysis. Very applicable.
Brother, instrument companies advertise their end product; they don’t advertise that their solid-body bass sounds better unplugged. They use the term “resonant “ in that sense. And that’s OK. It’s in the dictionary.
You are right, but that’s not what people mean when they advertise it. That’s OK too.
You are right, but that’s not what people mean when they advertise it. That’s OK too.
D
Deleted member 165050
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This applies to *anything* that vibrates. The distinction between acoustic and electric instruments is irrelevant. I get that if someone hasn't studied acoustics or worked in vibration analysis this might not be obvious.
This is where I stop responding, because you can't understand the difference between the note being rendered acoustically or electrically by Inductance. Have a holly-jolly new-year!
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I'd try saying one affects the other, but I won't. Happy meaningless date digit change to you too
@Killed_by_Death points out that vibration energy is distributed throughout the vibrating system from the string, sapping energy from the string. This transfer of vibrational energy is resonance. Nowhere in the system is there any appreciable destructive interference (unless you were to change the system or its energy). In that sense, KBD is 100% correct.
@D.A.R.K. gets the terms, but they don’t really apply much here, hence correct but not applicable.
It’s always nice for people to agree, KBD. It’s OK for others to use resonance to mean what they mean, and it’s OK for you to point out that resonance means something different physically than figuratively or metaphorically.
I think the best part about this thread is the learning opportunity that it’s usually not constructive or helpful to pick a fight over semantics and think in false dichotomy, especially when this is correct:
The resonant frequency of the system isn’t always “good” or “bad” in itself. (Though sometimes I guess it can be) It has character!
What a good learning experience for us, but no need to argue!
I've found that the very best place I can go to learn about physics is the Basses forum on TalkBass. 
Some people are willing to learn, others just want to argue that their 'opinion' is correct, that's where the semantics 'debate' starts, but it never ends, until someone just walks away, figuratively.
I've found that the very best place I can go to learn about physics is the Basses forum on TalkBass.
It all boils down to the second law of thermodynamics:
There is no free lunch.
Fine, but can you at least give me a discount on some of the fries in your avatar?
So, let’s say you knock a maple wood block… The result is a high frequency sound and vibration spectrum. Then you build an electric bass out of it and it will resonate and suck that high frequency out from the vibrating string? Then the bass would sound “dark”? What am I missing?
D
Deleted member 165050
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I am just going to say you are incorrect. Destructive interference occurs within solid body bass guitars as has been proven by multiple formal studies and that interference is transmitted to the amplified sound. That is why basses have dead spots, and there is a specific vibration analysis paper I've posted elsewhere that proves this conclusively, using a Precision as the study instrument. The same principle applies to constructive interference or live spots. Vibration analysis is not something you can can debate the semantics of. As always, opinion is no substitute for formal education and experience.
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So, let’s say you knock a maple wood block… The result is a high frequency sound and vibration spectrum. Then you build an electric bass out of it and it will resonate and suck that high frequency out from the vibrating string? Then the bass would sound “dark”? What am I missing?
Basically spot on. Each bit of wood has a natural resonant frequency. If you attach a vibrating string to it (which is moving at the string’s resonant frequency), then some of that energy will transfer to that bit of wood. If the bit of wood resonates near the string’s resonant frequency, then more energy will transfer more efficiently to the bit of wood.
In an electric instrument that depends on pickups, this means less vibration in the magnetic field of the pickup and less induction of current to the amplifier.
In an acoustic instrument, then as long as the bit of wood is in a good place (think the top), then it moves in resonance with the string very efficiently and the mass of air that moves is “good”.
I think technically the solid body instruments render their sound by transduction. Inductance happens to solid body instruments with magnetic pickups, but it isn't what generates the electric current.
I am just going to say you are incorrect. Destructive interference occurs within solid body bass guitars as has been proven by multiple formal studies and that interference is transmitted to the amplified sound. That is why basses have dead spots, and there is a specific vibration analysis paper I've posted elsewhere that proves this conclusively, using a Precision as the study instrument. The same principle applies to constructive interference or live spots. Vibration analysis is not something you can can debate the semantics of. As always, opinion is no substitute for formal education and experience.
Ps thread locking in 3... 2... 1...
Very respectfully and in the spirit of a good conversation:
For our purposes, we proposed a string-neck-body vibration and KBD rightly points out that energy absorbed By the neck/body part of our imaginary bass saps energy from the vibrating string, and this happens because of resonance. Totally cool and correct in my mind anyhow.
I can accept that in the real world there is constructive and destructive interference at many phases of whatever wave we want to measure. I’d be surprised if there weren’t. If we want to include a part in our model that accounts for that behavior, the following must be true:
—since our bass is unamplified, all energy contributed to the system besides energy from its mass and temperature comes from our finger plucking the string. Our system is in air that will vibrate.
—That energy will cause the string to resonate at its fundamental frequency and the amplitude will decay in a predictable manner. It will resonate at secondary frequencies as well.
—Any waves created in other parts of the system, including neck, body, and any part that tends to vibrate will be of lesser energy than what was contained in the initial introduction of energy (plucking the string).
Further, we could expect that the waves measured at any point in the system may be in phase or out of phase anywhere from [0->2pi]. If any of those waves interact along our system, then they can act constructively or destructively with one another.
Therefore constructive and destructive interference would be all over the place. Arguably even in the string itself if it weren’t completely uniform in density and diameter. But that’s not what we are talking about. KBD was discussing precisely only resonance as a vibration-damper in the string. Also wave interference will be only a small part of energy transfer, much smaller than conductance/resonance through the parts of the system.
Here's why:
—In order for waves from the body to interfere with the waves in our string, the body first has to resonate at or near the string’s fundamental. No resonance, No interference! (Constructive or otherwise). Every bit of interference that might occur happens because energy has been transferred from the vibrating string!
--Because the energy input comes with a pluck of a string and no other energy is put in the system, you will not get any energy input to interfere constructively with the string. The energy will always decay, never get stronger than it was at the string. It won’t get louder. It won’t vibrate at a bigger amplitude. Basic laws of physics won’t let it. It will not account for a “live spot” in an unamplified instrument. A "live spot" just comes from less resonance at the neck. A good analogy would be a truck towing a load over a flat road. The truck can pull the load, and the load's momentum may carry the truck if the motor stops, but that momentum came from the truck's motor in the first place. It will never push the truck more than the truck pulled it. The bass will never increase the string's energy more than the string increased the bass's energy. See the first and second laws of thermodynamics.
—As for destructive interference, such interference will always be some fraction of the energy conducted through the string to the second oscillator. The amount of energy conducted either direction will always be less than what was contained in the previous vibration. This means that conductance of mechanical energy through the neck occurs primarily in one direction, from higher amplitude, higher energy parts of the bass to the lower energy parts, and the conductance backward along the system will be negligible as compared to conductance from low to high. The string will “interfere constructively” with the neck but that is called resonance. A bit more complex analogy: this is like the truck coasting to a stop using no breaks. The truck and the wheels all have momentum. The plucking finger is like the acceleration of the truck and the coast to a stop is like the decay of vibration. The truck and wheels will coast until they stop. The wheel's momentum may serve to push the truck along, but unless they are weighted improperly, the truck's velocity will slow along a predetermined curve and will not get any faster on its way down the road. See the second and third laws of thermodynamics.
--The out-of-phase sound waves may have some small contribution to our thought experiment, but not much. They could be more important in a steady-state system. Consider a bass bowed by an infinitely long bow. The consistent increase in energy supplied by the bow would make the amplitudes and contributions of the interfering waves more meaningful, and the system would reach a steady state that is different from the one above, but I still posit they would be a small fraction of the energy of the vibrating string.
--TL;DR constructive interference can happen, but I suspect not enough to make a large or frequent difference and likely more or less cancel out most of the time. Hence, not very appreciable or important. A relatively small effect, in my opinion, compared to the rest of energy conductance.
— two engineering paper abstracts that propose dead spots are due to neck vibration/resonance due to conductance of partial and fundamental vibration, with no mention of interference:
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Humbly, if you have any source or math that contradicts any of this, please share it! Anything at all. I have tried to find the paper you cited and cannot find it.
No one does, they're just trying to 'yank my chain' at this point. 'transduction', LMAO!
