Can The Sound Of A Pickup be Infuenced By Wood Types

[alantig]

I burst my thong.

I did that once.

But not in the front.

 

[aristotle]

Actually, I think the original topic is a good and interesting one. IKAL was pretty clear in his original post that he was talking about changes to the actual way that the pickup behaves as a result of the wood type that it's mounted in rather than how the combination of pickup / rest of guitar sounds.

My initial reaction was that of course the pickup doesn't change its electrical behavior depending on the wood that its mounted in. Sure it will output something different depending on wood type and other things, but that's because the physical string is affected by those things. The input / output properties of the pickup stay fixed. I hadn't considered Les' point about microphonics....which would indeed change the input / output relationship as a function of the mechanical system surrounding the pickup. Not sure that it's a very important factor with modern pickups, but maybe. One way or the other, I hadn't seen that question asked before, and even if I had, not sure what the big deal is about posting it.

 

[bluefade]

Are most modern pickups mounted on spring loaded adjustable carriages ? Do the strings on most electric guitars not cross over and send their vibrations through a metal bridge and a bone or synthetic nut ? I have never seen a guitar made that the string vibration was directly transferred to the guitar wood . That would be an interesting experiment to try . Carve the nut right out of the neck wood and the bridge out of the body wood . Les's microphonic explanation carries the most sense for me , as this is a phenomenon I have witnessed , since I have been playing.

 

[veinbuster]

If I was designing a guitar pickup, I would not want its response to change with the wood it was mounted in. I don't consider this a particularly challenging bit of engineering.

That is not to say I wouldn't consider tailoring the pickups response to favour a particular wood.

 

[László]

If I was designing a guitar pickup, I would not want its response to change with the wood it was mounted in. I don't consider this a particularly challenging bit of engineering.

You might want it to be responsive to the type of wood the guitar is made of, however. Like a good mic responds to the subtleties and characteristics of a voice in various ways, some euphonic, some accurate, some highly colored.

In that case, its response (in the sense of the sounds it outputs) would change depending on the information was fed into it. And that might be a desirable quality that you'd want to engineer in. Otherwise you'd have a pretty sterile guitar.

Moreover, judging from the many bad microphones in the world designed by intelligent engineers, it could be a fairly challenging bit of engineering because it involves taste and judgment.

However the REALLY important question is how much wood a woodchuck could chuck if a woodchuck could chuck wood?

This question can only be answered in the PRS vault.

 

[veinbuster]

Moreover, judging from the many bad microphones in the world designed by intelligent engineers, it could be a fairly challenging bit of engineering because it involves taste and judgment.

Microphones and electro-magnetic pickups are very different beasts. One measures the movement of metal, the other measures the movement of air.

I've only commented on electro-magnetic pickups.

I'd like to respectfully suggest you consider the possibility that bein very knowledgable about the use of an object, does not imply expertise in the construction of said object.

It is also worth considering that in a disposable age there are many reasons for bad products other than the complexity of the engineering.

 

[László]

Microphones and electro-magnetic pickups are very different beasts. One measures the movement of metal, the other measures the movement of air.

But a good magnetic pickup, traditionally, is somewhat microphonic.

That's not a bad trait, unless you're an engineer.

That's why they get potted. And even the method of potting affects the microphonic behavior.

Surprise! Not being an engineer doesn't mean that I know nothing about how magnetic pickups work. I do understand the theory.

There are things that are as much about taste and art as they are about engineering. Pickups are among those things.

Here's a nice article on the art of potting pickups. In it Lollar, the builder of the pickups, says that he wants to preserve some of the microphonic quality, or the pickups will sound dull and lifeless:

http://www.lollarguitars.com/blog/2014/01/what_is_potting/

This is what I'm talking about when I say that pickups need to respond to the input from the wood a little.

 

[veinbuster]

But a good magnetic pickup, traditionally, is somewhat microphonic.

That's not a bad trait, unless you're an engineer.

That what was behind my early comment regarding picking up voice without the strings. The combination of the strings and the pickup has much in common with some microphine design. Specifically where one component of the microphone moves with the sound waves and another element of the microphone measures that movement, which become the source of the signal chain.

So yes, that becomes part of the whole package and the guitar itself is a big, fairly inefficient microphone. The pickup designer has to be aware of that total package and put the microphonic effect under the control of the user of the end product. As a player, I can cancel the microphonic effect simply by muting the strings. Any microphonic effect internal to the pickup itself would be outside of the guitar players control. This would be a design flaw.

 

[László]

That what was behind my early comment regarding picking up voice without the strings. The combination of the strings and the pickup has much in common with some microphine design. Specifically where one component of the microphone moves with the sound waves and another element of the microphone measures that movement, which become the source of the signal chain.

So yes, that becomes part of the whole package and the guitar itself is a big, fairly inefficient microphone. The pickup designer has to be aware of that total package and put the microphonic effect under the control of the user of the end product. As a player, I can cancel the microphonic effect simply by muting the strings. Any microphonic effect internal to the pickup itself would be outside of the guitar players control. This would be a design flaw.

See my added reference to an article by the respected pickup designer, Lollar.

Some design "flaws" aren't flaws, they're necessary, or at least musically useful.

Distortion in guitar amps would be one example of a musically useful "flaw" that engineers tried to get rid of with early solid state amps, and that Fender tried to get rid of in increasing the headroom from their blackface Twin to their silver face model. Most players overwhelmingly prefer the blackface model with less headroom and higher distortion.

Many players prefer the highly microphonic early PAF pickups.

Choosing which "flaws" to leave alone and which ones to correct, is where the art comes in.

A purist engineer might do things by the book, and produce a guitar that would be horrible to play. On the other hand, a talented engineer, with great musical taste, might produce a fantastic synthesizer.

 

[bluefade]

The debate between Les and the Vein is a wonderful example of the use of LOGIC that is BASED in TWO different CAMPS...WELL DONE guys...VERY entertaining , at the least, and educational too !

 

[rugerpc]

The debate between Les and the Vein is a wonderful example of the use of LOGIC that is BASED in TWO different CAMPS...WELL DONE guys...VERY entertaining , at the least, and educational too !

And amazingly, they are both arguing the "yes" answer to the original question.

 

[László]

And amazingly, they are both arguing the "yes" answer to the original question.

Haha! You're right. But why "yes" happens is something inquiring minds want to know, right?

 

[veinbuster]

Haha! You're right. But why "yes" happens is something inquiring minds want to know, right?

Often the why is more important than the answer.

 

[László]

Often the why is more important than the answer.

You bet. So here's what I tried today just to make sure I'm not crazy (wait...ok, I'm crazy, so let's change that to "just to make sure I'm not completely ignorant").

On my McCarty with 58/15s, I damped the strings with my palm and tapped very, very lightly on the wood body and neck. The tapping came through the amp, clear as day. Try it. YMMV.

I was damping the strings over the largest area I could with the palm of my hand, and not putting the strings against the frets, pickups or fretboard. I don't believe the strings were vibrating, I used the fleshy part of my palm.

I believe the tapping noise was evidence of the microphonic tendency of the pickups. This I think is supposed to happen with good pickups.

 

[bluefade]

SO, This means that ACTIVE PICKUPS are NOT MICROPHONIC ?...YES...

 

[veinbuster]

SO, This means that ACTIVE PICKUPS are NOT MICROPHONIC ?...YES...

I think the two are independent, not in that they don't influence each other, but in that being active does not imply microphonic or not. Similarly being microphonic does not imply not active.

 

[László]

SO, This means that ACTIVE PICKUPS are NOT MICROPHONIC ?...YES...

No.

 

[veinbuster]

On my McCarty with 58/15s, I damped the strings with my palm and tapped very, very lightly on the wood body and neck. The tapping came through the amp, clear as day. Try it. YMMV.

I was damping the strings over the largest area I could with the palm of my hand, and not putting the strings against the frets, pickups or fretboard. I don't believe the strings were vibrating, I used the fleshy part of my palm.

I believe the tapping noise was evidence of the microphonic tendency of the pickups. This I think is supposed to happen with good pickups.

Interesting, and perhaps indicative of a microphonic element, but I wouldn't consider it conclusive.

Let me try an example away from the guitar. If I tap the wall, there is enough damping between the physical connection between my hand and my ear that I can be quite confident that I hear the tap - with my ear being the microphone and serving its primary purpose. If I bang my head against the wall, it is more difficult to assess what portion of what I 'hear' is the sound wave rather than the physical vibration transmitted through my skull. If Mike Tyson punches me in the side of the head, there is a very high probability that what I hear is not a sound wave, but the physical trauma. And I probably don't care much because the pain receptors are going to override the signal my ears send to my brain anyway, assuming my skull is thick enough that I remain conscious.

Sometimes lying in bed I can hear my pulse. As mighty as my heart is, it does force enough blood to my head that the sound waves are strong enough for my ears to detect them. What I hear is the physical vibration. My ear doesn't know the difference. I don't consider this a design flaw, because most of the time it is irrelevant to my ear's purpose as a microphone.

so...if instead of tapping the guitar, you tapped a table - as hard as you want with whatever you want (except the guitar, a different guitar is OK) - and that came through the amp, you would have conclusive evidence of a microphonic tendency.

 

[Michael_DK]

Whether the vibrations are transmitted to the pickup via the surrounding wood or via the air doesn't make a difference as to whether the pickup is microphonic or not.

 

[László]

so...if instead of tapping the guitar, you tapped a table - as hard as you want with whatever you want (except the guitar, a different guitar is OK) - and that came through the amp, you would have conclusive evidence of a microphonic tendency.

Yes, that would be a clearer indication, but what we know about pickups and microphonics is that the movement of the wire winds around the magnet are what creates the phenomenon. Potting is used to prevent this movement, to a greater or lesser degree, depending on the pickup.

In this way the wire winds around the pickup's magnet behave somewhat like a moving coil microphone's coils and magnet. http://www.neumann.com/homestudio/en/what-is-a-dynamic-microphone

One has to remember that it isn't the diaphragm that causes the electrical signal in a dynamic mic, it's the movement of the coils attached to the diaphragm, moving relative to the stationary magnet (in certain designs the magnet moves instead, but it's the movement of the wire relative to the magnet that creates the signal).

This also happens to a much smaller degree when the wire winds around a pickup magnet respond to vibrations -- even though they aren't designed to facilitate that movement, and even though they aren't attached to a traditional diaphragm. But to a degree, I'd say that the body of the guitar itself can behave like a diaphragm on a microphone.

Without a specially designed diaphragm to pick up the noise, it takes a more physical vibration to move the windings of a pickup relative to the magnet, compared to a mic. So a microphonic pickup is going to need a lot more vibration, which it gets from being attached to the guitar body. It's not going to be vibrated enough by air, except in the case of feedback.

While the guitar body becomes akin to something like the mic's diaphragm, its movements from vibration are much smaller. In fact, the reason a hollow body guitar is more sensitive to feedback is simply that the top of the guitar is thin, and freer to move; therefore, it is more likely to behave and vibrate like a diaphragm. When the top moves a lot, the wire around the magnets in the pickups moves a little. And you get feedback.

This is why the solid body electric guitar was invented.

A solid body guitar, on the other hand, is less likely to behave like a diaphragm because it isn't as free to move due to its thickness, and is therefore less likely to in turn vibrate and move the wires around the magnet in the pickup, and therefore, feed back.

But that doesn't mean it doesn't vibrate when a string is plucked, or when you knock on the guitar body.

Because they don't have a proper diaphragm, microphonic pickups aren't as sensitive to sound waves as a mic. So they're more likely to respond to vibrations in the guitar body than to picking up noise external to the guitar.

However, very loud signals from guitar amps do affect microphonic pickups and make them howl - and we've all experienced this as feedback, and the reason feedback can be musical is because it's reinforcing the note the player is playing via both the vibrating guitar and the vibrations from the loud amp.

In any case, I don't think you're going to get much knocking on a table unless the guitar is sitting on the table, because in the case of a microphonic pickup, to a degree the guitar body becomes the diaphragm of the "mic."

Please forgive me for not using scientific terms here, but I'm trying to explain what I know about this without the benefit of equations and so on and while I understand how this all works, I am not able to explain it as easily as a scientist or mathematician can with equations and the like.