The Fender Jazz Bass has been at the echelon of the rhythmic bass arsenal for over five decades now.
Whether it’s the traditional stacked controls on your Jazz bass or the three-knob layout. You should always start by learning what each pickup offers and its tonal functionality.
That’s why in this post, I’ll break down in detail the controls on a J Bass guitar and each pickup’s function. Let’s get started.
What do the knobs on a Fender Jazz bass do?
The modern Fender Jazz bass has three basic controls. The knob closest to the neck controls the volume of the neck pickup (warmer tone.) The knob closest to the bridge pickup controls the volume of the bridge pickup (brighter tone.) The knob closest to the input jack adjusts the master tone of both pickups.
Jazz Bass Controls – What They Do?
Primarily, the neck and bridge pickup knobs function to ‘blend’ the amount of volume for each pickup. Whereas the tone knob serves as a master tone. Now let’s look at each knob more closely…
(1.) Neck Pickup Knob – (Closest to the Neck)
On a Jazz bass, the neck pickup is positioned close to the fretboard. Meaning the neck pickup captures ‘warmer’ and ’rounder’ tones.
Therefore, increasing the neck pickup volume, the tone becomes increasingly deeper, rounder, and less defined.
Like on any bass, the neck pickup knob adds warmth, fullness, and less articulation.
You will notice the more volume you add with the neck pickup, the tone becomes rounder and deeper with less ‘bite’ and ‘snap’ when plucking with a pick.
Blending maximum low frequencies combined with minimal volume from the bridge pickup offers a super deep tone. Ideal for ’round,’ deep, and smooth bass lines (especially when plucking with the fingers.)
Now, as expected, the more you turn up the knob, the more prominent these qualities become. In other words, the more volume from the neck pickup, the ’rounder,’ ‘deeper,’ and less defined the bass sounds.
With a well-managed neck control, you can expect to set the basis of your bass sound. Be it mellower or simply enhancing the low-end presence.
(2.) Bridge Pickup Knob – (Closest to The Bridge)
In contrast, The bridge pickup is positioned closest to the saddle. Meaning the bridge pickup captures ‘brighter’ and ‘thinner’ frequencies.
Therefore, turning the bridge pickup knob clockwise makes the tone brighter and more defined. Adding more ‘attack,’ ‘bite,’ and ‘punchiness’ to the bass signal.
The bridge pickup is set to make the presence of your Jazz bass a punchier one by stressing the high-frequencies. It spikes the contours of your mix, providing brightness, treble, and a ‘cutting element.’
The bridge pickup knob is key to adjusting how bright, punchy, and cutting you want your bass tone to be.
For example, Slap bass players love maximum volume from the neck pickup. Because a bright and articulate tone optimizes the ‘snap’ and ‘poping’ tones of slap bass playing. Allowing the tone to sound defined and more percussive in nature.
(3.) Master Tone – (Closest to The Input Jack )
Since Jazz basses typically sport passive pickups, the single tone knob has a more specific function.
With passive pickups, the master tone knob focuses on adding or cutting treble frequencies from the overall tone.
Once your volume on each pickup is set, the tone knob controls the overall brightness/darkness of the signal.
In a way, the tone knob ‘fine-tunes’ the treble and bass frequencies from the overall signal.
With a maxed tone knob, you tend to get the air and fret noise that makes for a spankier sound. Treble makes everything brighter and more defined.
On the other hand, minimizing the tone knob gives a warmer and deeper feel to your overall sound. While it conserves the treble coming from your pickups, it diminishes the brightness and ‘high-end’ signal frequencies.
Jazz Bass Pickups – Are They Humbuckers or Single-Coils?
Jazz bass pickups have been, traditionally, single-coils. Fender was looking to offer a balanced tone with an enhanced attack and the possibility to provide an aired sound.
The single-coil has been the traditional option given its open sound with rich top-ends. Nevertheless, they balance out both frequencies to harmonize while capturing the string’s natural sound. This is thanks to their single coil of wire, responsible for this aired reception that picks up noise from outside.
A common misconception is that these pickups lack bottom-end. It’s simply focused on highlighting treble, enhancing attack and definition in a single piece. However, this latter quality enables you to control it by catching it.
On the other hand, Humbuckers are wired and configured to cancel external frequencies from beyond your strings, hence their name. It bucks the humming.
Since humbuckers are two single-coils reverse wounded together, they produce an overall hotter signal. This makes for a fatter-sounding midrange and bottom-end.
Do Jazz Basses Have Active or Passive Pickups?
The Jazz bass is synonymous with passive pickups, let alone the standard bass is. Up until 1970, passive electronics were the norm.
Every record had a passive bass on it, and thus the tradition stuck. On the other hand, Fender got really creative with the invention of active pickups, so they started making their own models.
Some of their most popular active pickup models include the Deluxe Active Jazz Bass and the P/J Hybrid Bass. Among the most popular.
Passive pickups have a rather appealing quality, their simplicity. Their natural warmth and more mellow sound can be shaped with two basic settings, tone, and volume. This is pretty much what most players need.
Now, passive pickups can seem a tad limiting to some fans, considering nothing is boosting your signal. So players with passive pickups tend to be more aware of tone embellishment from different sources. Be it pedals or amps, the passive choice is one for you to paint on.
On the other hand, active pickups offer a powered preamp, which gives players various tone alternatives from the bat. The other pro for an active setup is that the onboard preamp produces more output and gain for ‘hotter’ aggressive tones.
This certainly allows you to cut through the mix with more edge and tonal superiority, but there is one downside. Active pickups and basses require 9V batteries at all times, mainly because the preamp needs it to remain functional.