A bass guitar amplifier head is the part of an amp that takes in signal from your bass guitar and modifies or shapes it, ultimately producing sound either subtle or dramatic.
Some bass amp heads feature built-in overdrive effects ranging from “mellow warmth” to heavy distortion, and some even feature patch bays to connect pedals.
Bassists depend heavily on the speakers in a bass guitar amplifier head to translate small electrical audio signals from their instrument into larger ones that drive speakers with drumming-inducing levels of volume. Some bassists opt for separate power amps and speaker cabinets for greater control of tone and impedance of their setups.
No matter whether it’s a single-channel solid state transistor bass amp or one of the increasingly popular tube designs, speakers in your amplifier head are key. Tube amps often sound warmer and more natural at given levels of wattage compared to solid state transistor amplifiers; however, their additional components add weight and require more maintenance than their solid state counterparts.
Bassists seeking portability and ease of setup might opt for an amp head without speakers. While still powerful enough for most venues, these amps can be easily connected with any speaker that matches its tone and impedance, making them suitable for practice settings at home or studio as well as smaller venues where renting speaker cabinets may reduce costs.
Combo amps may not be as portable, but do provide the ease of transporting one unit directly to gigs. Combos tend to be heavier than bass amp heads and may prove challenging to maneuver on stage due to having an 8×10 speaker cabinet attached.
Many bass amps boast more than just a speaker output socket; many also include auxiliary ins and outs for connecting additional amplifier cabinets (if necessary), “send/return” jacks for creating effects loops, DI output and tuner outs; plus knobs to customize digital amp and speaker emulation settings such as Ampeg tube amp tones.
A bass guitar amplifier head, known as a power amp, converts small voltage audio signals into larger ones that drive speaker cones. These amps may use either tube (thermionic in the UK, “valve”) or transistor technology; hybrid designs even combine both technologies for maximum sound quality.
Tube-based bass amps typically produce warmer tones with reduced distortion than their solid state counterparts, and feature an EQ section equipped with several knobs that let you control bass and mid frequencies with boost or cut controls for each frequency range. Solid state amps may be more compact and quiet; their speaker cabinet size being reduced compared to their tube-based counterparts.
Wattage of amplifier heads can have a dramatic impact on their sound output. Higher-wattage amps may feature more features that make them easier to use; however, louder amps may put additional stress on components and lead to their failure.
Bassists performing in large venues may benefit from using a high-wattage amp with a larger speaker cabinet, as this will not only increase power and volume but can also better address feedback or other potential problems that may arise in larger venues.
At smaller venues or at home, those playing bass may prefer smaller amp heads. They tend to be much lighter and smaller than their larger counterparts, making it easier for transport. Some also feature a power-amp in jack which enables users to plug an external preamp pedal which bypasses their amp’s internal preamp/EQ sections.
Some professional-grade amps feature an audio crossover that divides the bass signal into two signals, routing low-pitched sound to cabinets optimized for its frequencies while routing middle and high frequencies to another cabinet specifically tailored for them. A crossover knob lets you set which frequencies are separated.
A bass guitar amplifier head may contain various features designed to prevent damage and minimize risk during use, including “protection mode” switches that prevent it from turning on without signal present, which reduces risk to players and can prevent injury from overheating speakers. Other safety features may include recessed power knobs and protective grilles for speakers; additionally, some models provide tuner output which makes changing pitch easier between songs.
An additional feature that can enhance the safety of a bass guitar amplifier head is a high-pass filter, which removes low frequencies from the signal to lower damage to components such as speakers. Furthermore, bass amplifier heads often come equipped with built-in distortion control that can create aggressive sounds.
No matter if a bass amplifier head features protection modes or not, it’s vital that its wiring and connections remain secure and undamaged. Loose or damaged wiring can cause an amplifier to overheat while also impairing performance. Furthermore, make sure the impedance of speakers matches with those of your amplifier head for best results.
Many bass amplifiers feature multiple input and output connectors, making it easier for bassists to collaborate with different instruments or friends who own different gear. Some bass amps even include direct out jacks that allow users to send clean signal directly into a mixing console for live performances; and there are others with line out jacks for advanced tone shaping purposes.
Most bass amps are designed for easy portability, making it simple for bassists to transport them between performances or recording studios. Lighter than combo amps and smaller than full stack amps, bass amps often come equipped with multiple carry handles and wheel mounts to facilitate transportation. Some models even run off battery power which makes playing in outdoor venues without mains electricity easier.
Bass guitar amplifier heads offer players with many effects for enhanced bass playing experience. This may include overdrive or distortion effects to add punch and grit to the sound of their instrument; an EQ section to customize tone; chorus/flanger effects built-in for user use; some amps even include shape buttons enabling bassists to boost specific frequencies with just the push of a button; as well as built-in effects like shape buttons that give control over tone at low frequency ranges and give control of tone control at mid frequency range.
Most bass guitar amplifiers feature a gain control to adjust the strength of signal being sent to speakers. A higher gain increases signal strength and makes for louder sounds. Bassists generally set their bass knob at 12 o’clock and adjust it until they achieve their ideal bass tone. Mid and high-mid controls give their sound weight and depth, providing control of sound weighting and depth. Increased high-mid and low-mid frequencies result in more clarity for bass sound while decreasing them can increase resonant frequencies, creating harsh or muffled sounds. The treble knob controls high-end frequencies that influence brightness of bass tone – bassists who play using plectrums may need to increase it in order to get that sharp, distinct tone they require.
A bass amplifier head may include a patch bay that allows bassists to bypass the preamp of their amp and plug in an external pedal preamp for different tones. Once activated, this pedal preamp can either feed back into their power amp for sound transformation, or go straight into their effects loop for maximum flexibility and power.
An amplifier should produce rich and full sounds, but even the highest-grade bass amplifiers must be taken care of properly to prevent damage or overheating. Check for loose connections or signs of wear-and-tear regularly; with proper care it should continue providing service for many years to come.