It can be difficult, confusing as hell to the untrained ear and possibly expensive, depending on your budget.
How can you tell (in advance) what pickup will be right for the sound you want?
If you don't already know, then you simply can't answer this question without help or a lot of work. You will have to rely on someone you believe you can trust. This could be a friend, a guitar repairman with a good reputation, a cool guitar shop known for their expertise, or even a pickup company that you have heard good things about.
There are many online sites with reviews of pickups from all the manufacturers. Validating the information found there is another matter altogether. Sound clips are great, but do they represent your guitar, your rig, in your environment? Pickup tone charts generally only talk about the characteristics of the pickup itself and might even confuse you more. If you are new to the pickup game, understanding all the vague jargon just doesn't happen overnight. Do you really want to go back to school just to change your pickups? I don't think so. You just want to improve your tone and get back to playing your guitar!
I will try to lay down some simple guidelines to get us at least close, if not on the mark in choosing a pickup. And for the sake of keeping it simple in this article, I will focus on single coil pickups for Strat-style guitars. Let's simplify and break it down:
First, your existing pickups must be properly adjusted...
for a true evaluation of what your guitar is capable of. Bring the pickups as close as possible to the strings without physical, or sonic (particularly on the low E string, usually manifested as weird overtones) interference. This is usually about 1/8” from the high E when the string is depressed at the last fret, and as somewhere around 1/8”- 1/4” clearance on the low E depressed at the last fret.
Describe what you like and don't...
like about the sound of each pickup. Is the neck meaty? Rich? Sound like Stevie? Is the middle clean, strong but full, rhythm supreme? Does the bridge have good, clean bite and cut through? Do your combinations have that quack? Is there hum canceling for bad hum situations?
Analyze the tone personality...
of your guitar. Consider the weight of your guitar, particularly the density of the wood used, which is the number one factor in the tone. The less dense a body is, the lighter it will be and so on. The neck will certainly play a part, as well as hardware types, and so on, but generally to a lesser degree. An often-used generalization is that maple necks are brighter than rosewood- necked guitars. This is a factor, but a very light guitar will almost always sound warmer with any quality set of pickups (warmer is not always enough for tone hounds!). A medium weight instrument can go either way, while a heavy guitar typically is thinner or bright sounding while breaking your back at the same time.
I often hear complaints that a guitar sounds too weak overall with the bridge position being way too thin, often to the point of being unusable. It is clear in these cases that a stronger pickup is needed in the bridge position. That's why Rio Grande, like most pickup makers, offers more than one style (output) of Strat pickup. These guitars may need a hotter pickup, with more signal to work with, such as our Muy Grande or Dirty Harry (which is actually a miniature P-90).
In most cases pickup configuration, as in all things, is personal taste. For myself, a tapered set is an absolute necessity. Your guitar is physically tapered from the day it was made. A tapered (often referred to as calibrated) set of pickups is only natural. Smooth and round for the neck, solid and compatible for the middle, and strong and punchy for the bridge. That is a set getting stronger from the neck towards the bridge. You can have all these things and still retain pure natural Strat tones without going overboard.
We will change pickups in guitars, usually for one main reason: we do not like the sound we are getting from the guitar. The pickups are the most important variable you have control of on your guitar. Try a new set, you will be amazed at how much it may affect your sound. Once you get a set of pickups you're happy with, you won't have to fight your rig for tone!
One thing is certain...good tone makes you feel and play better. There are lots of pickups out there, so happy hunting!