How does resistance relate to tone? And what else does it affect?
I went thru the pickup FAQ's and didn't see s simple, direct answer.
I went thru the pickup FAQ's and didn't see s simple, direct answer.
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Pickup Resistance
- Thread starter felis
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- Apr 18, 2008
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There isn’t a simple, direct answer. DC resistance is just one factor of many that affect tone.
All else equal, more resistance means more output and a more mid-focused tone.
But all else is usually not equal.
All else equal, more resistance means more output and a more mid-focused tone.
But all else is usually not equal.
The reason the tone is more mid-focused is because more DC resistance, all else being equal, i.e., wire, how it is wound, magnet structure, bobbins, etc., usually means more wire on the coil. This means more inductance, which our ears perceive as a bump in the mids. Also, more wire usually means more intra-coil capacitance, which shunts highs, which our ears perceive as a drop at the top.
- Apr 18, 2008
- 16,020
- 1
- 31,740
- Disclosures
- I'm highly opinionated and extremely self-assured
All else equal, yes. Although it will also result in less output.
I think a more accurate way of putting it is this.
The less resistance, the less the pickup adds its own character to the equation. In other words, the less resistance, the more the pickup simply produces whatever that particular hunk o' wood with some strings and metal bits has going on. It's just lead of a factor in the overall tone. But, again, it comes at the cost of lower output.
Also, some prefer the character a hot pickup adds to the tone. So there's that.
In short, it's one more rabbit hole to explore for yourself. Good luck with that. Many of us have been down half a dozen or more..... pickups, strings, body composition, etc. And don't even get me started on amps.
So - I guess another way to say it is that less resistance wouldn't result in more highs or more lows,
but as resistance decreases, the tone approaches what it would be without any amplification at all.
That still leaves me to wonder why more resistance increases mids though.
The "all else being equal" statement is key - it is very hard to keep all else equal. If you're using the same wire gauge, you'd think that 5% more resistance would mean 5% more turns. Sometimes it is, but often it isn't. Wire gauges have tolerances, and at the gauges we're talking about, the thickness tolerance is in the neighborhood of 10% in diameter. Resistance of a given length of wire is proportional to the inverse of the cross sectional area - a 10 percent change in diameter is a 21 percent chance in cross sectional area. So, if you have two coils, the one with 5% more resistance might have more turns, and it might also have less.
And now for the kicker - there is more than one wire gauge in use in pickups. I know Leo would be shocked, ad he seemed to be stuck on 42 gauge, but there are other gauges. When you want to make a pickup hotter, you end up filling the bobbin too much, and at some point, you go to a smaller gauge (which has a higher number, just to be confusing). I have some pickups that have the same general construction, but the bridge model has abut 20 percent more resistance. That's not unusual - bridge pickups are often wired a bit hotter, but in this case, it's the same number of turns - the two models have the same inductance, and given that they're wound on the same magnetic structure,, that means the same number of turns. So, 20 percent more resistance, same inductance, the wire is thinner - probably a gauge thinner.
Higher inductance doesn't cause a bump in the mids. All the magnetic pickups we have in our basses will, when operated with into a cable, resonate at some frequency - that frequency depends on the inductance, and the capacitances of the cable and the capacitances inherent between the coil windings. More inductance doesn't cause a bump, but it lowers the frequency of the bump a bit.
Magnetic pickups have very flat response at low and low mid frequencies, then at some frequency there is a bump (more output), and after that, the response drops off at 12 dB per octave. The frequency of the bump and how high it is are the only things different in the electrical response of pickups - when people talk about "mid scooped" pickups, there isn't really much you can point to in the pickup that would do that, other than to a really minor degree.
Below about 1kHz, all the pickups in your basses are (unless the tone control is down) very flat devices. The location of the pickup(s), and the comb filtering that results from that - there if you want to talk mid scoops, bumps, etc, in that realm there's a LOT to talk about.
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Not exactly. MORE resistance can result in LESS low amd/or highs. Less resistance simply affects the circuit less. Thus, more of the true tone of the bass itself (all inherent factors that contribute to tone) shine through.
Less resistance does not INCREASE anything. It just doesn't take away anything (or much of anything).
More resistance increases output at the expense of highs and lows.
Less resistance means less output, but more of tye frequency spectrum of the bass (whatever that means for that particular bass) comes through. It doesn't "increase" anything.
Less resistance may or may not mean less output - as I stated above, you can get more or less resistance by changing wire diameter, without changing the output level. If you reduce resistance in that way, it will increase the height of the resonant peak (less resistance means that resonance is damped less, so the peak goes up). Sometimes...less is more.
Actually, Leo used 43 gauge wire on Tele neck pickups, although I don't think he used 43 gauge wire anywhere else, and it wasn't seen on a Fender pickup otherwise until, I believe, some Texas Strat pickups. Please correct me. But your are correct about wire inconsistency. Here is a chart of Seymour Duncan's actual measured wire (which appears to be with insulation intact, when comparing the "spec" diameter of the copper on industry charts) on pickups over the years as he repaired original pickups, so these diameters may also vary as the thickness of the insulation varied as well: Vintage Fender© guitar pickup spec info
I think you’re right - Leo had an early fling with 43 gauge, but settled into a rut shortly thereafter.
On the link is a quite good site. DCR basically tells you only how much wire is wound on the bobbin. Inductance (Henry) perhaps tells more than any other PU's physical quantity. Surprisingly few seems understand that a passive guitar and bass pickup is an interactive LCR circuit (PU-pots- cable- amp input). And that is important to understand how PU works as it works.
BuildYourGuitar.com :: The Secrets of Electric Guitar Pickups
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Lemme is an excellent read on the subject of pickups. I seem to recall he wrote somewhere else something to the effect that pickup manufacturers are fiercely protective of their designs and would not publish resistance measurements if it risked exposing useful information about their products.
You can also check out the pickup builders thread here on Talkbass, where pretty much every possible aspect of pickup design is discussed and analyzed, in very easy to read ways.
Freekmagnet
Commercial User
Resistance by itself doesn’t tell you anything useful about how a pickup is going to sound. There’s so many other factors about what goes into a pickup design, like the magnetic structure, the materials and the size of the magnet, the shape of the coil, where the magnet is placed in relation to the coils, the gauge of wire, how many turns of wire… you get the idea. Resistance really only tells you the length of the wire wrapped around the core. However, that measurement can be deceiving; a 7K pickup wound with 44AWG (finer) wire will have fewer turns of wire than the same pickup wound with 42AWG wire. The finer wire has more resistance per length.
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just from the reads I've done, the theory of DCR & output is relative to the family of pickups and everything about the pickup being equal except the thousands of turns of wound wire. That is if we were accept that we had 2 identical bridge or neck pickups with the same magnets that were magnetized/charged to the same spec measure for strength, the same bobbins, the same gauge wire, the pickup that has more K winds of wire would have more output than the one with fewer windings.
"For guitar pickups, the most common gauges are 42 AWG, 43 AWG and 44 AWG. There are other gauges too, but they aren’t as frequently used. The effect of having a thinner wire is dramatic. Because it’s thinner, you can wrap more wire around the bobbin, in effect lengthening the strand of copper wire. And the longer the wire, the stronger the signal will be that the coil will induce..."
One can read the rest of it here:
Guitar Pickup Inductance: What It Is And Why It Matters
"For guitar pickups, the most common gauges are 42 AWG, 43 AWG and 44 AWG. There are other gauges too, but they aren’t as frequently used. The effect of having a thinner wire is dramatic. Because it’s thinner, you can wrap more wire around the bobbin, in effect lengthening the strand of copper wire. And the longer the wire, the stronger the signal will be that the coil will induce..."
One can read the rest of it here:
Guitar Pickup Inductance: What It Is And Why It Matters
