It was relatively late in my working on this site that I thought it would be of interest to have a Q and A page. My intention is to present and discuss some of the same subjects as the items in the other pages, just not in the same detailed way. Let’s see how it works out…
On this page there are questions concerning different subjects. They are kind of helter skelter at this point, but I will try to organize them a little better as the list grows, probably group them in subjects. OK here we go, I have provided answers based on my knowledge and FACTS, no hype and no myths:
Q: I have heard that in the original humbuckers from Gibson, the ones there is so much fuzz about, the coil with the screws has more turn of wire than the slug side. Why is that?
A: The reason you typically hear is the the process of winding pickups was very lax back then. My explanation is that, first of all, these people knew what they were doing and the reason for the difference is probably to even out the amount of inductance in the pickup coils. The same number of turns in the coils would yield different inductances due to screw versus slug. A difference in magnetic media in the pickup coil means a difference in inductance for the same number of turns.
Q: I think it must have been from the same source, but it was insinuated that hand wound pickups are “good” and machine wound are “bad” and the winding method means everything when it concerns a pickups “tone”. Any truth to that?
A: NONE what so ever. None that has any practical importance. The most important thing is the NUMBER of turns. And the magnet used, something that is discussed in detail on this site.
Q: More from the same or similar source (sorry). The claim that screws with a certain carbon content is better at “conducting” magnetics is better than another and that affects the output of the pickup. Same thing with old and modern magnets?
A: This is nothing other than pure myth. I assume that you have not seen any scientific evidence from the claimer? I think I have heard this as well, a person claiming that the old (“vintage”) magnets were to different specifications than the modern magnets of the same grade (A2, A5 etc). Not true, even if it was, it would not make any difference. I have read the original patent and there is no mention of this!
Q: Pickup wire, you hear that a different wire or an old wire can vary in thickness when drawn resulting in a difference in “resistance per foot”. What difference does this make in the output of the pickup?
A: This is simple: NONE. Please see description of coil resistance variation.
Q: What is “tone”? You hear the word mentioned in a lot of different contexts, that’s my tone, my tone has improved, my pickup’s tone, this is how you get a better tone, tone wood, I have a guitar, it’s got great tone….
A: That is true, everybody is talking about it, but nobody is actually defining exactly what they mean. This means, of course, that you as a reader or listener gets more and more confused. It has become such an all encompassing buzz word that it pretty much renders the word meaningless. That is why I refer to it as “enot”, a word that is just as meaningless. Bottom line, it means just about anything you would like it to mean. Can someone please define what they are talking about! By the way, I am trying to explain it from a pickup standpoint on the “Guitar Electronics” page, it is done with graphs and explanations. It would be very instructive if everyone would do that, too much to ask? If you look at it this way, if you are just tossing the word “tone” out there without any further explanation, you tend to adopt it as you please so the meaning becomes what you understand, so would everyone else. In the end, each person has an understanding that differs making the whole thing abstract and meaningless.
Q: I was watching a video about winding pickups, the person doing the video claimed, while showing a sketch of a vibrating string. Instead of the string being shown as a half wave with the two end points, the half wave was made up of a high frequency overriding the half wave. It was claimed that the amplitude near the end of the string is smaller that the amplitude at the center of the string and therefore the frequency produced near the end was higher the the center, is that correct?
A: No that is incorrect. First of all, if I understand the string picture right, it is depicted incorrectly. The string does not behave that way at all, it appears like the attempt was to show the fundamental, but I do not know what the high frequency is supposed to resemble. Let us stick to the fundamental and forget about the high frequency for now. The amplitude of this fundamental is the string excursion at the center of the half wave, measured as the distance from the rest point to the point on the string there. What is meant to be said is that the displacement of a point of the string depends on the distance from the bridge, as one of the endpoints. What the pickup in a position transfers is dependent on the “speed” of the string at that particular point. The location will give a specific frequency pattern of harmonics, but the fundamental frequency is exactly the same in any spot on the string, after all they all take the same amount of time to complete 1 cycle, it is just that the distance is shorter the closer you get to the ends of the string. It is the speed of the point on the string that is transmitted by the pickup. This is elaborated on in the Pickup Physics page.
Q: I saw in a video that it is possible to magnetize and possibly demagnetize a magnet of a typical pickup magnet material to any value I want?
A: No, that is not possible. A given magnetic material used for permanent magnets will be magnetized to a very specific strength that is relevant to that magnet type. The measure for the magnetic field is given as B, the flux density, and a magnet magnetized will maintain this flux density for a very long time, it is called “permanent” for a reason. The unit for B is either Tesla or Gauss (be careful with the way you pronounce Gauss, you do not want it to sound like something you dress wounds with, like gauze). For more detailed information, please see the “Permanent Magnets” section on the Pickup Physics page.
Q: Does the magnet type have anything to do with a pickup’s output frequency range or quality? Does stronger magnets give higher treble?
A: No and no, it produces a magnetic field, B, the flux density. The flux density is different for different magnets, the pickup output voltage is related to the flux density B in a way that with the same string, same location of pickup, same string height, same string movement, the output voltage is proportional to the change in B with time. For more information, please see the pickup page. No magnet type is “warmer” than another magnet type and so on….I will discuss this on the “Amplifier” page.
Q: On the subject of stronger magnets, do I get a much louder output if I change the pole pieces in my pickups from AlNiCo to Neodymium, that are at least four times stronger?
A: No, you do not! The Neodymium magnets are much stronger, but it is not the absolute strength of the B field that the output voltage is dependent on, it is the change in magnetic field that the string is able to produce that matters, please see the Pickup Physics page.
Q: I have watched a lot of videos where the person is taking a cheap single coil pickup with steel slugs and ceramic magnet and claims a lot of improvement if replacing the pole pieces with AlNiCo magnets and removing the ceramic magnet, of course. Is this true?
A: Well, improvement is a relative term, but it does lead to some changes in the output voltage and frequency spectrum. I have presented some specific examples on both the Electronics and Pickup pages. Like I said, if there is an improvement is subjective, but if you look at the measurements you see the differences. Depending on the magnetic medium in the coil(s), the inductance and capacitance of the pickup can change quite a bit and these parameters determine the frequency range which may interfere with the audible range.
Q: Does “scatter” winding a pickup give you a better “tone” that another type of winding?
A: No, since we do not know what “tone” the person claiming that this word means. No, even if we did know. As a conclusion, you must have realized so-called “scatter” winding does not give you a frequency spectrum advantage. There are curves on the Electronics page to show this. Bottom line, you hear this repeated all the time, “my pickup’s tone”. What tone is that, I ask? A pickup does not have a “tone”, claiming you can hear an implemented improvement is nonsense, the emphasis on “hear”, what you hear is the output of the the amplifier, it is the amplifier and speaker shaping the tonal picture for you, not the pickup! It appears that people relate this to the pickup capacitance and that this is the ultimate thing that determines a pickup output. It is NOT. If you want a very special winding method, please try the so-called “Back Winding” method that produces the lowest capacitance! Other than that, please see on the guitar electronics page what really determines the capacitance! It might be under Resonance Measurement.
Q: Can you measure pickup capacitance with an LCR meter?
A: NO, not just no, but absolutely not. The measurement method an LCR meter uses is fine for real capacitors, the same method does not work at all for a coil capacitance. I have a special section on how to determine pickup capacitance. Pickup capacitance has become an obsession for some video makers out there that also wind pickups. There is no capacitor in a pickup, there is an equivalent capacitance resulting in a resonance frequency for the pickup. If you determine the capacitance from the resonance measurement you will find that it is relatively small compared to other capacitances in the signal chain, e.g. cable capacitance. As you will see in the Electronics section, the variation you can expect in pickup capacitance can come from many places, how you wind the pickup coil is by far the least relevant. Not only that, but the possible variation does not have any influence on the useful frequency range of the pickup output range.
Q: Can I measure L and R, Inductance and Resistance, with an LCR meter?
A: With a good quality meter, yes.
Q: A lot of websites, both for pickup makers and non-pickup makers go to great length to discuss the pickup (coil) resistance. How important is coil resistance?
A: If you have read the Guitar Electronics page, you may know that the resistance of a coil does not matter at all. Resistance can vary quite a lot without having any influence on output voltage what so ever. Other parameters, such as wire gauge (AWG) and temperature will influence the resistance, but the influence on sound is zero. As far as using resistance as a measure for a pickup output, it does not mean the the output is proportional the the resistance.
Q: Inductance is rarely mentioned on pickup maker’s websites, is it not important?
A: Inductance is very important. This entity has just about everything to do with the sound. I will again refer to the Electronics page. Why it is not or only rarely mentioned, I do not know. Maybe it is because it is not as straight forward (as resistance) to measure, that is. In my opinion it should be mentioned as prime parameter. Make sure that you understand that resistance and inductance is not the same, I heard in a video “it is resistance, also known as inductance”, I can only stress that is very wrong!
Q: Is there any commonality between coil inductance and voltage induced in the coil due to a string moving.
A: Generally no. I guess, if you look at it this way, a coil along with slugs, screws or pole piece magnets represents an inductance depending on what is “in it”. There can be quite a variation, please see the Electronics page. An induced voltage occur between coil lead ends when the flux through the coil is varied, the faster the variation is, the higher the induced voltage.
Q: Twisting output wires from a pickup, assuming there is only two does that help on cutting down noise.
A: The practice is normally referred to a “twisted pair” of wires and can be beneficial when you have wires with opposing signals such as a pickup output signal. The basic principle is shown in Fig 1 and it is not unlike what is used in humbucking pickups, where you have two coils of reverse polarity. In case of a radiated signal present at the location of the coils the sum of the two outputs will cancel the input radiation and therefore give a noise free output. Same thing with the twisted pair where you create a string of positives and negatives resulting in noise cancelation. It is not completely ideal because noise that is injected via capacitive coupling into the wires will not be eliminated. You may have experienced this by putting you hand on the guitar body in an area where there are wires and you will hear it! Noise like this can be prevented by proper shielding as described on the Guitar Shielding page.
Q: Can I “degauss” my magnets to get the “tone” I want?
A: Please see elsewhere about “tone”, the answer is NO. Degaussing is a process used on navy ships to minimize their “footprint” for detection by the enemy, its purpose is to completely remove any magnetization of the hull. You do not want to do that to pickup magnets. Using a much stronger magnet to try to “degauss” your pickup as described in a few cases on YouTube, you might end up “destroying” the pickup magnets by completely removing or even reversing the magnetic polarity. There are cases where pickup magnets demagnetize over time, typically in single coil pickups where magnets are placed side by side all with the same polarity up. It should be something that takes decades, I have a Fender from 1985 and the pickups as far as I can measure have not degraded. It is after all 35 years old! Other than with magnets, rough physical handling, like hammering on the magnets can demagnetize, other methods are not typically available to most people. A natural question to ask: “why would you want to try to lower your pickup’s magnetic field”?. Sounds sort of silly to me!
Q: If I boil my old guitar strings will they be as good as new?
A: No, absolutely no chance of that! I can see how this myth came about, though. I think it started like this, new strings as a final process in the manufacturing are annealed, this is a high temperature treatment that is used to “reorganize” a metal, it does, however, take place at a much higher temperature than boiling, I mean much higher than 212 F in boiling water.
Q: Does wire matter for pickup winding. Both coating and copper AWG?
A: Coating for the typically wire types used for pickups is rather irrelevant, it just needs to be isolating and I recommend using the more modern types. AWG refers to the size or diameter of the copper wire itself and is a measure for the resistance of the wire, the higher the AWG, the higher the resistance per length. There is a huge fuzz about pickup capacitance out there that is way blown out of proportion!
Q: Does it give you any advantages to wind a pickup using silver wire?
A: None what so ever. It may give you a slightly lower resistance than copper for the same number of turns, but since the coil resistance is by far the least important parameter, it does not make any difference. Oh, only on price….
Q: Is it worth buying expensive guitar cables. I am hearing that really costly cables will give you a better sound?
A: Not really if copper purity and oxygen content is being promoted in that context. Getting a medium priced cable can be the best choice. You just have to pay attention to a few things. One is the “shield” resistance, which in most cases in not given, but since the cable is not really shielded in the EMI sense, the resistance is playing an important role because it is keeping the noise level down because the amp end of the shield will be close to Ground since the amp chassis is, or should I say should be, grounded via the third prong in the power cord. The second thing to look out for is the cable capacitance, this is where the really cheap cables are easy to recognize. Here is an example, I got a cheap guitar cable with something I ordered, it looked very nice looking, braided instead of plastic cover, it was about 4 ft long and I compared it to a 20 ft cable of reasonable cost. As it turned out, the cheap cable had 3 times the capacitance and it was only 1/5th of the length! So beware!
Q: Can I eliminate cable capacitance, I need at lease 15 ft between guitar and amp?
A: With a regular cable, the answer is no. You can minimize the effect of the cable by using the proper “active” pickup. You can eliminate the capacitance, of course, by using a high quality wireless system.
Q: Is it true that all the hype about PAF humbuckers has any merit?
A: Unequivocally NO! I have heard mention of the early PAF having the “best tones on record”. There is that word again, “tone”, nobody knows what it means. The best on record, are we talking about records from the 1950ies or what? I don’t think they sounded that good, I am from that era. There are pickup makers that go out of their way to duplicate every detail, inconsequential ones like mounting screws, wood spacer, pole piece screw material and bobbin material. Even coil wire. These things have no influence on the sound or how the pickup converts the string movement to electric voltage. They may look “authentic”, but so what? Nobody can see them anyway. Now what all the authentic material can do if someone slick can convince you that you hear a difference is a different story. I guess the power of persuasion can be pretty intoxicating!
Q: Speaking of PAF bobbins, the material MUST be that puke stinking stuff. Does that make any difference?
A: None, electrically speaking. The only difference is that butyrate stinks! I have heard an interesting comment that it has something to do with the “resonance of the bobbin”, that this parameter may be different from other materials in modern pickups. Resonance in a bobbin, whatever high frequency that is, having any influence on the sound or the conversion to induced voltage? It is so far fetched that it is borderline ridiculous.
Q: Speaking of pickups, we cannot avoid talking about feed-back. What is feed-back and does wax potting make a difference?
A: As far as I can tell, wax potting does not help. You get skeptical when you consider what feed-back is. Yes, I have seen videos too, where someone shows the difference between none and wax potted pickups. Did you notice that they put a hand damping the strings when demonstrating how wax potting “helps”. What is feed-back? Well, it can be appearing in many contexts, but in this case we are talking about interaction between guitar and amplifier, in this case the feed-back is positive, which is leading to instability which means that amplification of the signal presented at the input of the amplifier increases until a limit is reached, in some cases the internal amplifier circuit will oscillate, not unusual with a high gain amp. What creates a signal at the input of the amplifier? Answer, a vibrating string. Remember, the vibration must create a change in flux through the pickup coil, primarily, only a vibrating string can do that, but anything that can create a voltage at the input to the amplifier can qualify, noise is a good example. Only humbucking and shielding will do that, not waxing. Almost 35 years ago, I went to a seminar for, I forget what it was for, but it was about guitars and amps at a music store. The guy unplugged the cable and held it up against the speaker of a cranked amp, and it squealed like a pig, the speaker was creating a voltage between the tip and the sleeve of the cable plug, amplified by the amp creating a positive feedback. Why is it so sensitive, well every electronics engineer would know that, it is called high input impedance of the amp! In this example there is no pickup present, but plenty of feedback. I could go on and on about this, but I will end with this question: Have you ever experienced feedback in a high gain closed circuit situation, meaning where there is no speaker involved, where your guitar signal goes to an amplifier and you are only listening using head phones? My guess is that you have not! Now, earlier I said “primarily” and that there might be other ways so I have created a separate page called “Microphonics” that draws out some interesting aspects on this.
Q: I watch video after video of “how to solder guitar electronics” and a lot of time and effort is spent on soldering wire and bending back lugs to the pot case and call it “grounding”. No one has ever explained why they go through such effort, can you explain why?
A: Interesting question, it appears to me that the reason for a missing explanation most likely is that the people doing this don’t know themselves. They do not have the faintest clue why they do this, they do this because it was done this way as far back as the 1950ies when the whole thing began and it has just been done like that ever since. I cannot tell you why the wiring is done this way, mainly because there is absolutely no good reason why you solder wire to each pot case and run wire to other pot cases, let alone bending back lugs and solder to the case of the pot. I have personally looked everywhere, watched tons of videos and not once has it been mentioned. What bothers me the most: This practice has not even been questioned! Why does it bother me, because it is totally unnecessary, even harmful to do this (you might want to check the Shielding page). Come to think of it, I might place a drawing of the simplest, but correct wiring on the electronics page. And to ad insult to injury, it is always referred to a “grounding”, nothing could be further from the truth! Sorry to say, but I think tradition took over from rational thinking, so no wonder why they do not know.
Q: Now we cannot avoid this, but I am wondering which would be the best capacitor for my guitar “tone” circuit?
A: If we are talking type and brand, I could go on a long rant here, but sometimes it is impossible to go up against myth and marketing, but I will just say that for this type of application there is absolutely no difference between capacitors, regardless whether they cost $50 or c50. In my long electronics career, I have be involved in selecting capacitors for many different applications, from the simplest to the most demanding. In those cases there are rules that apply to which capacitor you can use. In case of guitars, there is absolutely no reason for a specific type or brand, none. I think, again, tradition has a lot to do with it. If you can “hear” the difference between capacitor types, bless you! No instrument known to man can measure a difference that makes a difference! I would suggest sticking with film capacitors. I know that ceramic capacitors are cheap, but they do not have a place in this type of application.
Q: Is a cable with one single wire surrounded by a shield really a shielded cable?
A: As a EMI engineer I can definitely say: NO, it is not a shielded cable. Even worse, if the cable is unclad so this “shield” can create short circuits all over the place! For further information, please see the shielding page. A shielded cable has more than one wire inside the shield and these wires are the only ones carrying signal and are at all times separate from the shield!
Q: I know that you are not an expert in amplifiers, but can you explain the “Presence” button on the amp and what it is there for?
A: Well, I am not claiming that I am an expert on amps, but I am more of an expert that people that claim that they are! You have your normal Bass, Mod and Treble knobs that are normally referred to as the “tone” stack in the amp. These regulate the frequency response of the amp. The Presence knob is not part of this stack, but it does affect the frequency response of the amp since it is connected with the amp’s feed-back circuit. The feed-back, in general, is “opposing” the input signal and the Presence circuit can regulate the amount of high frequency content there is in the feed-back circuit, so if an amount of the the high frequency is filtered off the feed-back signal, it will let more of the input signal high frequency through. It is sort of an additional Treble knob, except the “tone” stack is located right following the initial amplifier stage (typically), the Presence circuit is located late in the amplification chain, typically in connection with phase splitter in the output stage.