Ok, I think I may be able to explain that. My friend and I wired a 6 position switch each with different resistance values. The higher resistance seemed to change the tone in that it cut the treble. (We were using a schematic for a Lo-Z coverter outta guitar player). So Changing the resistance in a non-linear fasion may also cut/boost treble slightly in a non linear fasion.
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Scientific: How does physics apply to the different sound of particular basses?
- Thread starter WarriorJoe7
- Start date
Ok, I think I may be able to explain that. My friend and I wired a 6 position switch each with different resistance values. The higher resistance seemed to change the tone in that it cut the treble. (We were using a schematic for a Lo-Z coverter outta guitar player). So Changing the resistance in a non-linear fasion may also cut/boost treble slightly in a non linear fasion.
Correct, the loading changes. This can cause a loss of high frequency content i.e. overtones in passive systems. It's caused by the impedance variation relative to the amp input impedance and the cable does introduce it's own effects.
An onboard buffer circuit (unity gain amp) will isolate the pickup from the loading effects of passive pots and the amp input. Same for pretty much any active onboard eq systems.
wow i didn't know that!! that is pretty awsome.
Yup, any pre-amp will do that for ya, usually, lol. Certainty is not an easy thing in science.
Ah yes that is a very true statment! With any science field there is alway uncertainty. but that is why we love science...
Well i guess i will be learning about what ya'll were talking about really soon.... since i will most likely be double majoring in Physics now 
YEAH!! I am happy i decided to do that.. especially since i need alot of physics for my field of work... 
If all you're concerned with is buffering to prevent loading of the pickups, a simple op amp follower with a pair of 9V batteries for a split supply is pretty much ideal. <$5
I've considered adding one to my bass. I still may if my overcomplicated control setup causes any problems.
The sound of an electric bass is a combination of two separate systems: acoustic and electric, and the physics of each is very different and it's a lot easier to understand them when studied separately. I took a class by Professor Rossing* on acoustic science and the textbook for the class (which he wrote) is an amazing resource for understanding how sound is produced as well as perceived by listeners. Here is a link to some resources that can help you find what you're looking for:
[Invalid or Expired Link Removed]
Someone posted something like "The string vibrates and makes noise and I'm happy" and that's perfectly OK as an explanation and you don't need any math or physics to understand the concept. But if you desire to know more than that (like what specifically is happening to the string as it vibrates and how exactly does it make the air vibrate around it) then you can get as technical as you want and never in your lifetime run out of things to learn about the acoustics of your instrument. Just understanding how a vibrating bass string makes noise involves a large investment in physics and math, and it's probably accurate to say that to really get a feel for it you'd have to get a physics degree or the equivalent education. The electrical part of the problem is a whole extra deal and again, you can go as deep as you want into it and never run out of learning. You'd need to gain the level of electrical engineer to really start to get a feel for how electrical circuits and related systems transform acoustic energy into electric energy and back again.
*Thomas D. Rossing
Physics Department
Northern Illinois University
DeKalb, IL 60115
The Science of Sound - Rossing
Principles of Vibration and Sound - Rossing
http://www.amazon.com/Science-Sound-3rd-Thomas-Rossing/dp/0805385657
[Invalid or Expired Link Removed]
Someone posted something like "The string vibrates and makes noise and I'm happy" and that's perfectly OK as an explanation and you don't need any math or physics to understand the concept. But if you desire to know more than that (like what specifically is happening to the string as it vibrates and how exactly does it make the air vibrate around it) then you can get as technical as you want and never in your lifetime run out of things to learn about the acoustics of your instrument. Just understanding how a vibrating bass string makes noise involves a large investment in physics and math, and it's probably accurate to say that to really get a feel for it you'd have to get a physics degree or the equivalent education. The electrical part of the problem is a whole extra deal and again, you can go as deep as you want into it and never run out of learning. You'd need to gain the level of electrical engineer to really start to get a feel for how electrical circuits and related systems transform acoustic energy into electric energy and back again.
*Thomas D. Rossing
Physics Department
Northern Illinois University
DeKalb, IL 60115
The Science of Sound - Rossing
Principles of Vibration and Sound - Rossing
http://www.amazon.com/Science-Sound-3rd-Thomas-Rossing/dp/0805385657
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john turner
You don't want to do that. Trust me.
the broad scope of the original post makes this more a topic for Miscellaneous than Basses. i'll move it presently 
.
.It's true, there's always more to learn. Certainly though, you don't need a Physics or EE degree, or even any formal education to get a pretty reasonable understanding. Generally the math required is really pretty trivial.
Some good deductive reasoning, and some reference material (like the internet) will get you a long way.
I think the biggest skill to master is crap detection. Most any information you need is out there somewhere, you just have to learn what to ignore, and what to look into further.
Mongo2: Likewise. I've never taken any classes even vaguely related to any of this since my high school physics class.
-Nick
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Two neat pages about pickup position
http://www.till.com/articles/PickupResponse/
and mixing
http://www.till.com/articles/PickupMixing/index.html
http://www.till.com/articles/PickupResponse/
and mixing
http://www.till.com/articles/PickupMixing/index.html
I'm not a physicist, but I am a statistician (with an expertise in experimental design). This is a little OT from your direct question, but it might help explain why there is so much disagreement and constant discussion on the impact of pickup position, types of wood, etc., etc.
There are linear, direct effects of things (called 'main' effects in the experimental design/statistical analysis literature) and non-linear effects (one specific type on non-linear effect that weighs on your issue is called an 'interaction'). An interaction occurs when the level of one variable (e.g., wood) has a differential impact on an outcome (e.g., tone) based on the level of another variable (e.g., string material and voicing).
Many times there are significant 'main effects' (i.e., maple boards tend to sound a little brighter than rosewood boards), and also significant interactions (maple boards with pickups that have a more upper mid content seem differentially brighter than rosewood boards versus that same comparison with darker voiced pickups that don't amplify those frequencies, etc.).
As you can see, this quickly gets complicated, and in the example above we are only talking about the simplest of non-linear effects (the two way interaction). The current state of statistical analysis really bogs down above the level of three or four way interactions (e.g., pickup x body wood x string brand x headstock mass, etc.). The problem is, to really understand how this stuff all works, we are probably talking about 10+ way (and probably much higher level) interaction s(body density x headstock mass x neck material x neck mass x string voicing x pickup voicing x etc., etc.). If you take the variation across individual pieces of wood into account, then we are into interactions of a MUCH higher level.
As a result, when you try to understand a non-linear, interactive situation by only talking about linear main effects (body wood, fretboard material, etc.), the results are confusing and seem to not make sense (i.e., some say rw boards are brighter than maple, some say maple is brighter than rw... put in the context of these non-linear interactions, everyone is probably right). This is why it is so hard to predict the weather.... where there are probably 100 way interactions that are 'significant'.
One way to think of the difference between 'science and art' is this non-linearity. Once you get to higher level multi-way interactions (i.e., what makes an instrument sound good?, why do some paintings or sculptures 'work' and look beautiful while others don't?, etc.), it's more guesswork and 'inspiration'... i.e., art! So, IMO, that's why most great luthier's are considered 'artists' and not 'scientists or engineers'. It's also why some of the theories about why some things sound the way they do espoused by some luthiers (even the famous ones) seem silly to some of us!
There are linear, direct effects of things (called 'main' effects in the experimental design/statistical analysis literature) and non-linear effects (one specific type on non-linear effect that weighs on your issue is called an 'interaction'). An interaction occurs when the level of one variable (e.g., wood) has a differential impact on an outcome (e.g., tone) based on the level of another variable (e.g., string material and voicing).
Many times there are significant 'main effects' (i.e., maple boards tend to sound a little brighter than rosewood boards), and also significant interactions (maple boards with pickups that have a more upper mid content seem differentially brighter than rosewood boards versus that same comparison with darker voiced pickups that don't amplify those frequencies, etc.).
As you can see, this quickly gets complicated, and in the example above we are only talking about the simplest of non-linear effects (the two way interaction). The current state of statistical analysis really bogs down above the level of three or four way interactions (e.g., pickup x body wood x string brand x headstock mass, etc.). The problem is, to really understand how this stuff all works, we are probably talking about 10+ way (and probably much higher level) interaction s(body density x headstock mass x neck material x neck mass x string voicing x pickup voicing x etc., etc.). If you take the variation across individual pieces of wood into account, then we are into interactions of a MUCH higher level.
As a result, when you try to understand a non-linear, interactive situation by only talking about linear main effects (body wood, fretboard material, etc.), the results are confusing and seem to not make sense (i.e., some say rw boards are brighter than maple, some say maple is brighter than rw... put in the context of these non-linear interactions, everyone is probably right). This is why it is so hard to predict the weather.... where there are probably 100 way interactions that are 'significant'.
One way to think of the difference between 'science and art' is this non-linearity. Once you get to higher level multi-way interactions (i.e., what makes an instrument sound good?, why do some paintings or sculptures 'work' and look beautiful while others don't?, etc.), it's more guesswork and 'inspiration'... i.e., art! So, IMO, that's why most great luthier's are considered 'artists' and not 'scientists or engineers'. It's also why some of the theories about why some things sound the way they do espoused by some luthiers (even the famous ones) seem silly to some of us!
