Will a Humbucker Pickup Fit in a P90 Slot?

Imagine that you are thinking of making some small modifications to your guitar to improve its tone

You spent hours researching and found out that a good option is to replace your pickups.

Once you have enough money you go to the store to buy your brand new humbuckers but an idea penetrates your mind. 

Will these pickups fit in the cavity of my P90s? Should I buy them and try them out? Before you invest your precious money read on

Although humbuckers and P90s have similar measurements and sizes they are not exactly the same. Depending on the type of P90 slot your humbucker might match but if not, modifications will be needed.

As replacing pickups is an issue that challenges both beginners and experienced guitarists, we will deeply explain how is the process with humbuckers and P90s. 

Here at GearAficionado, we want to help so read to the end and this will be your new expertise area.

Are humbuckers and P90s the same size?

When referring to pickup size we need to focus on two main aspects, dimensions, and shape. 

Humbuckers are wide rectangular blocks often covered with a metal protector and screw at both sides.

Although P90s share characteristics, they are also the same shape, they differ in certain features, for instance, measurements. 

P90s are rectangular shaped as well but they are 35 mm wide plus 85 mm long, similar to Humbuckers but narrower.

Humbuckers present a 78 mm length but due to screw cavities their reach almost 85 mm long, similar to P90s length. 

However, when we pay attention to their width we notice differences. 

As mentioned, Humbuckers are wider, they offer a 39 mm width and even though are almost the same, they do not match. 

Therefore, despite presenting alike features and shapes, they are not the same size.

Would a P90 routing work for a humbucker?

The above explanation shows how different the two pickups are in terms of size. 

However, not everything relies on the differences between these pickup models.

The P90s are still pickups with a single magnet while the humbuckers involve two single coils together. 

If we refer to wire routing, although the buckers have two types (two-conductors and four-conductors wiring) they are quite similar.

The problem arises when we try to install a humbucker in a cavity that previously housed a P90. 

The available space might be sufficient for the length of the buckers but definitely not for the width, so adjustments will be needed.

Fortunately, Soap Bar P90s are not the only pickups of this model, there are also very similar ones called Dog Ear P90s. 

Their name is due to they have an extension on both sides where the screws are placed, which fits much better with the Humbuckers that have a similar design.

Although when placing the humbuckers there may be a gap, it will be almost imperceptible and will not interfere with its performance. 

It is all a matter of measuring carefully and doing the job cautiously. 

Are there some alternatives to this?

As we have explained, placing a pickup in a cavity that does not belong to it is usually a difficult task. 

This does not only happen with P90s and humbuckers, as generally pickup shapes and sizes vary according to the model, it happens in most cases.

Fortunately, some companies have designed pickups in the shape of another, which makes the process much easier when it comes to interchanging them. 

In the case of humbuckers, there is a design called humbucker-shaped-P90.

As the name suggests, this is a humbucker with the dimensions adjusted to fit a P90s routing. 

This is great also because this way the guitarist does not need to re-route his instrument, which involves destructive woodwork.

Is the wiring required for humbuckers and P90s the same?

Contrary to what most players might think, this pair of pickups are more alike than thought. 

The comparison relies on their construction because while P90s are a type of single-coil pickup, humbuckers present two magnets.

You may wonder how is possible for them to be similar if they present a dissimilar number of magnets but that does not make them so distant. 

Humbuckers have two magnets because they consist of two single coils stacked together, resulting in comparable wiring.

Apart from the wiring, the two pickups are generally employed in pairs. 

That means we can find both buckers and P90s located in the bridge and neck positions of electric guitars. 

What is more, they share the three-way pickup selector like in Les Pauls and Telecasters guitars. 

The main difference appears in the number of knobs, P90s are commonly controlled by a master volume pot and a potentiometer to tweak tone whereas humbuckers present a volume and a tone pot for each pickup, resulting in a total of four knobs.

Moreover, P90s work perfectly with a 250k potentiometer but as buckers comprise two single coils, they need a 500k potentiometer to show their real performance. 

That’s because you have “two pickups in one” so you will require to double the value to have the full humbucker power.

Although is possible to see guitars with a three-pickups-config, both P90s and humbuckers, are not that common and are mainly found in custom pieces. 

The standard in these cases involves just two pickups.

Would humbuckers sound good alongside P90s?

Being the two of them mid-output pickups and offering pretty coincident tones, P90s and buckers could do an amazing job when paired.

Despite being the former a single coil pickup type, has more points in common with humbuckers.

First of all, since they both use the same specs, it is quite simple to combine them. 

Besides, the tone of the P90s is in the middle of the single coils and the humbuckers, like a blend of both.

The punchy attack of the P90s combined with the tight tone of the humbuckers will offer you interesting sounds. 

In addition to that, you can decide whether to use a P90 in the bridge position and a humbucker in the neck or vice versa, both configurations will offer you a wide range of tones that will help you forge your personal style. 

Can you do this pickup swap on your own?

When it comes to modifying a guitar, several variables come into play. Most musicians think it is a difficult task, but if you are attentive it is not complex.

If you are comfortable soldering wires and feel capable of following a diagram it will be a piece of cake. 

Fortunately, for those who are reluctant to do the job, there is also a solution.

Whenever you are going to make an adjustment to your instrument it is advisable to consult a technician. 

They are professionals, they are dedicated to these tasks, and replacing a pair of pickups is an everyday task for them.

Last but not least, if the body of the guitar requires rerouting, again we advise you to see a technician or a luthier. 

Although many musicians say they know how to do the woodwork, a professional will always be the best and safest option.

Is this mod reversible?

Changing pickups generally brings some issues to bear in mind and that is because, in most cases, pickup models are distant in size. 

As you already know, P90s and humbuckers present a slight difference in their dimensions so, if you intend to install the latter in a cavity intended or the first extra routing will be required. 

Since we are talking about destructive work, it won’t be possible to come back to the previous setup due to you wouldn’t be able to put the wood back. 

In this particular case, the woodwork needed will enlarge the slots a few millimeters so coming back to the P90’s config won’t be tough.

There will be some space left but since the measurements are quite alike, it won’t be perceptible at all. 

Furthermore, if your pickups are Dog Ear P90s, no woodwork will be needed plus the mod will be reversible without any problem due to the screw holes matching.