Electric Guitar and Bass Output Impedance: A Technical Comparison

The output impedance of electric guitars and basses plays a crucial role in shaping their tone and interaction with amplifiers and effects pedals. This article explores the differences in output impedance between various models of electric guitars, as well as active and passive bass guitars.

Electric Guitars

Electric guitars typically have passive pickup systems, resulting in relatively high output impedances. The actual impedance values can vary significantly depending on the pickup type and configuration:

1. Single-coil pickups: These generally have the highest output impedance, ranging from 6,000 to 15,000 ohms. For example, a Fender Stratocaster with standard single-coil pickups typically has an output impedance of around 6,500 to 7,500 ohms.
2. Humbucker pickups: Humbuckers usually have a lower output impedance than single-coils, typically ranging from 7,000 to 12,000 ohms. A Gibson Les Paul with stock humbuckers might have an output impedance of approximately 7,500 to 8,500 ohms.
3. P90 pickups: These fall between single-coils and humbuckers, with an output impedance typically ranging from 7,000 to 10,000 ohms.
4. Active pickups: Like basses, some guitars have active pickups, like those sold by EMG, with much lower output impedance, typically ranging from 100 to 1,000 ohms.

It’s worth noting that the overall output impedance of a guitar can be affected by factors such as the volume and tone controls, as well as the pickup selector switch position.

Bass Guitars

Bass guitars come in both passive and active configurations, resulting in significant differences in output impedance:

1. Passive bass guitars: These instruments, like their six-string counterparts, have relatively high output impedances. A typical passive bass, such as a standard Fender Precision Bass, might have an output impedance ranging from 5,000 to 12,000 ohms, depending on the pickup configuration.
2. Active bass guitars: Basses with active electronics incorporate a preamp powered by an onboard battery. This results in a much lower output impedance, typically ranging from 100 to 1,000 ohms. For instance, a Music Man StingRay with active electronics might have an output impedance as low as 220 ohms.

The lower output impedance of active basses offers several advantages:

• Improved signal strength and clarity, especially when using long cable runs
• Enhanced ability to drive effects pedals and preamps
• Reduced susceptibility to noise and interference
• Greater tonal flexibility through onboard EQ controls

However, passive basses remain popular due to their simpler design, lack of reliance on batteries, and classic tonal characteristics.

Understanding the output impedance differences between various electric guitars and basses is crucial for achieving optimal tone and performance. While electric guitars and passive basses generally have high output impedances, active basses stand out with their significantly lower impedances. These variations can impact everything from cable selection to pedal and amplifier compatibility, making impedance an important consideration for musicians and audio engineers alike.