Lately, I’ve noticed more and more threads on forums about active and passive pickups. Usually, a war with one type on one side. However, those threads are usually misleading and full of generalizations made by people who have no real experience with both types of pickups. They usually will say the same rehashed things without ever having the real world experience of using an active pickup. In this week’s article, I’m going to clear up those generalizations and give you a better understanding of how pickups work and what the real difference is between active and passive pickups.
First though, you need to understand how a pickup works. Pickups work by creating an electrical current through the oscillation of the guitar strings through it’s magnetic field. That creates an AC current. For passive and active pickups, it’s a fairly low amount. Passive pickups are around 350-500mv average. Active pickups are in that same area of output, but where the two differ is the active pickup has a preamp build inside that boosts the ouput to volts, rather than millivolts.
An active pickup uses fewer turns of a heavier gauge wire, where a passive pickup would use more windings of a lighter gauge wire. Since the active uses that method of winding, that yields a lower output, but a more broad frequency response. Since that ouput is low, the pickup is boosted by a preamp built inside the pickup. This kicks up the output to around 1.5 to 2 volts for most models. That means that they will hit the amp harder and cause it to distort a bit more. That’s where the idea that active pickups are really high output. Technically speaking, they aren’t. The high output comes from the preamp, not the winding of the pickup.
Another aspect to active pickups is that the preamp needs a battery to function. Both of the major active pickup makers use 9V batteries with the ability to go up to 27V (using 3 9V batteries). More volts will give you increased headroom. There is a difference in using 18V as opposed to 9V, but the jump to 27V didn’t seem to yield any significant change. However, the argument is that they chew through batteries. While it is true that they do need a new battery, let’s look at the numbers. With one pickup, you’ll get 3000 hours of battery life. That equals out to a little over 8 hours of playing a day every day for a year, including a leap year. If you have dual active pickups, you’d have to play 4 hours a day every day for a year. Those numbers are for the EMG systems. Seymour Duncan’s Blackouts use a little more juice, but you’ll still get a lot of use before a battery goes dead on you. I replace my battery every 6 months or so and that works just fine.
Passive pickups don’t need a battery because they have no preamp inside. The current goes from your pickup, to the switch, to the pots, to the jack, and finally goes to the amp. And after more moving around finally ends up at the speaker where you finally hear it. On a note, amps boost the current from guitars way up to be able to make sound. So the guitar is sending current to the amp, the amp sends no current to the guitar. Still, ground your amp properly or you might end up medium well done.
So now you want to know how they sound. Up until recently, all active pickups were sealed and instead of pole pieces, they use bars of metal. However, EMG recently did a new set which combined the pole piece/bar. You might wonder why that matters. Well it equates to a different sound. Passive pickups with the pole pieces (some passives, such as the BL 500XL and SD SH-13 used a bar setup instead of individual pieces, occasionally referred to as a blade style) have a pluckier, more percussive tone. Actives used a bar which is not as percussive sounding, making for a smoother type tone. With the new pickup, you get the percussive tone but with the clarity and focused tone of the active pickup.
Passive pickups do sound a bit more natural, a more open type tone. They work well in a variety of areas and good ones are clear under high gain. They don’t have the sort of compressed tone that actives do. Think big AC/DC type rhythm chords. Active pickups can’t get that sort of open and airy sound to them. So if a more natural sound is what you want, passives are what you’ll want. Active pickups do have a more compressed type tone to them and yes, the preamp colors the tone a bit. However, they do not sound the same in all guitars. Different woods, different hardware, and different construction (solid, semi hollow, neck through) will have an effect on the overall tone. Anyone who tells you they all sound the same has either not tried actives or is making a generalized statement based on things they’ve heard others say.
I did an experiment years ago testing that. I took an Ibanez 1570 and a Fender Strat and swapped pickups. I used the 81 and 85 pickups for the test. The 85 is a very bass heavy pickup and in the basswood Ibanez, the low end was a bit much for me. It would work well for a rhythm player, but as one who goes back and forth I needed a change. The 81 was a much better fit, as it wasn’t as heavy on the bass side and had more treble to offset the basswood’s midrange type tone. However, the 81 in the Strat was far too trebly. Bass response was good, but it was just too much high end for me. So I put the 85 in. It gave a nice big tone that was both warm, but not overbearing in the bass and middle frequencies. It also tamed the high end a bit, giving me the bite I wanted without too much treble. Even now, I’ve got an 85 in an all mahogany guitar. While it is subdued a bit in the treble, the bass is perfect with good midrange. It sounds nothing like it did in the 1570 or in the Strat.
Actives are very clear under heavy processing (gain, effects) which is where they have a bit of an edge over a passive pickup. But in the end, its’ up to the guitarist to decide what it is they like. Is one better than the other? I don’t really think so. They are very different from one another and it’s all very subjective. I personally use both. Sometimes I want that tight focused sound, but other times I just want a nice open type tone. So in the end, it’s up to you. But hopefully here you can see some of those statements other people make are entirely unfounded.
If you guys want to hear the difference, I do have two guitars that are somewhat similar in construction, an Epiphone Les Paul Custom and an Washburn X-50 Pro. Both are a stop tail type construction and both are all mahogany. So I could record something onto my iPod and see about getting it on here.