Gearank

While the Ernie Ball VP Jr. 25K and the Ernie Ball VP Jr. 250K are very similar, there are a few differences that you need to know about. The first difference, and the most important, is that the 250K is intended for passive instruments while the 25K is intended for guitars with active pickups.

Another feature that separates the 250K from the 25K is that the 250K comes with a taper switch which allows you to change the volume reduction curve. The first setting gives a very even reduction in volume, while on the second setting the swell starts off slow and then gradually accelerate. The second setting is great for dreamy volume swells, while the first is great for fine-tuned control.

Key Features:

• Design: Volume Pedal
• Circuit: Passive
• Best For: Passive Pickups
• Dimensions: 2.4" x 3.5" x 10"
• Weight: 2 lbs

This unit uses a pulley mechanism as opposed to a pot, and gives you the option for silent tuning (with your tuner pedal being removed from the signal chain).

As stated above, while the string design is intended to increase the reliability of the pedal it’s actually reported to be less durable than more traditional designs. It’s also unknown how easy the string itself is to repair, and how widely available the components are.