FAQ - Technical Questions

::: PICKUPS :::

What is the difference between active and passive pickups?

In a nutshell, active pickups rely on external power.  Active pickups have less coils of wire and use a built in preamp to boost the signal to a usable level.  Passive pickups rely on more coils of wire.  Sonically, they can be fairly different.  Commonly, folks who enjoy active pickups will remark on the clarity of active pickups.  Players who like passive pickups will comment on the warmth of passive pickups.

Does my bass have active or passive pickups?

We have written an article that may be of help.  Check it out here.

Which pickups will fit in my bass?

The best way to check if a specific pickup or set of pickups will fit your bass is to take some measurements.  There are some standardizations in the industry, but unfortunately not enough.  Over time, brands change the pickups that they use, even in specific models. So...save yourself a future headache, and measure your pickups before you buy.  If you have questions about pickup fit, contact us.

Taking measurements: Try to get as high resolution with your measurements as possible. Measure to 1/16th of an inch or down to the mm.  We have nearly all pickups listed on our site with their measurements in both Metric and Imperial measurements. 

Most folks will find that they will get more accurate measurements using a ruler with Metric measurements in millimeters.  Often, a standard ruler will have both metric and imperial measurements on it.

P Bass Pickups:

4 string are the most 'standardized' pickup in the industry.  When investigating pickups, take a look at the images, if it looks like your pickup, then most likely it will fit.  There are two 'sides' to a P pickup.  One side gives magnetic coverage to the E and A string and the other side gives coverage to the D and G string.  They are always sold together and viewed as a single pickup.

5 string have some variance - pay close attention to a difference in the length of the pickup shells that make up the P pickup.  By in large, most manufacturers will use 2 shells that are of equal size.  Fender, on many models, uses two different sizes for their P shells - in this case, you will need a pickup made to accommodate this size.

Jazz Bass Pickups: 

4 string have some variance across brands.  Measure the length of the two pickups.  A standard jazz bass pickup set will have a slightly shorter neck than the bridge pickup.  Common/standard sizing is 3.60" (91mm) for the neck pickup and 3.73" (95mm) for the bridge pickup.  The most common exception are Made In Mexico jazz basses, certain years of these will have two neck size pickups.

5 string have significant variance within various brands and models and no real common or standardized sizing of pickup shells.  Measure the length of the two pickups.  Here are some common combinations:

Neck = 3.60" (91mm)  /  Bridge = 3.73" (95mm)

Neck & Bridge of equal length at 3.73" (95mm)

Neck = 4.0" (102mm) / Bridge = 4.1" (105mm)

Soapbar Pickups:

Lots of variations of Soapbars.  Take measurements of both the length and width of both your pickups, and compare to some various pickups listed on our site.  Aftermarket pickups from our suppliers have a great deal of overlap, and there are a several commonly used shapes.

::: PREAMPS :::

Should I use 18V or 9V battery with my preamp?

Most players in most situations will not hear a different between 9 or 18 Volts.  There is not a difference in output level.  There is a difference in the signal to noise ratio - this means that preamps using 18V will distort less as the gain of the EQ knobs is increased.....on paper.  We have not found this to be universally true in practice.  If your bass has a battery box for 18V, then indeed, wire the preamp to it for 18V.  If not, don't sweat it.

*If a specific preamp's specifications recommends 18 Volts, use 18 Volts.  This is the case for Aguilar's OBP1 preamp.

Do I need active pickups if I have a preamp?

Not necessarily...and in fact, rarely.  Most pickups in basses are passive, even when a preamp is used.  Determine if you truly have active or passive pickups.  This article should help.  

Do preamps come with knobs or do I need to buy them separately?

This is varies by manufacturer.  For the brands that we sell, here is the scoop:

Aguilar- No knobs included.

Bartolini - Knobs for stacked pots only (treble/bass stack or volume/volume stack).

EMG - Knobs included.

John East - Knobs included.

Nordstrand - No knobs included.

::: HARDWARE :::

How do I know which combination of Bass Side or Treble Side tuners I need?

For a right handed bass held in playing position, the tuners the are on the ceiling side of your headstock are sold as bass side tuners. The tuners which are on the floor side of your headstock are treble side tuners.  For Example, a Fender® 4 String Jazz Bass has 4 bass side tuners, and 0 treble side tuners.

For a left handed bass, the reverse is true.  The tuners that are on the ceiling side of your headstock are sold as treble side tuners. The tuners which are on the floor side of your headstock are bass side tuners.  For Example, a left handed Fender® 4 String Jazz Bass has 4 treble side tuners, and 0 bass side tuners.


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