The very first guitar amplifiers made their maiden appearance in the 1930s. These were designed to be used with electric guitars, and they worked by introducing rectifier tubes and electrolytic capacitors which enabled the generation of built in power supplies. Now, all you had to do was plug in the power supply into wall sockets. This meant that heavy and cumbersome multiple battery packs were no longer necessary.
Initially, guitar amplifiers were used in acoustic guitars. In the 1930s and 1940s however, Hawaiian music gained popularity, and these made use of amplified lap steel Hawaiian guitars extensively. Electronic amps for guitars thus became widely popular. The earliest guitar amplifiers made use of simple tone controls which provided control treble boost. However, the overall quality of treble and bass response was very poor because of the kind of loudspeakers used, and the controls. The amplifier themselves were very low on power with typical wattage being 15 watts or lesser before the mid 1950s. Some of the more enhanced models also included an electronic tremolo unit and/or spring reverb. Tremolo in the earliest fender amplifiers were termed as “vibrato”. In a fender amp, the vibrato amp of the Stratocaster was named a tremolo bar.
In the 60s, pioneering guitarists began to experiment with distortion effects that were produced by purposely overdriving or overloading the amplifiers. Prominent among these was the Kinks guitarist Dave Davies who created the earliest distortion effects by connecting one amplifier output into the input of another amplifier. The resulting sound was something that amp designers most probably never had in mind. As guitar amps began to evolve, manufacturers introduced integrated pre amplifier distortion controls. Other systems were incorporated to allow guitarists to generate these distortion effects safely and consistently. These effects included fuzz boxes too. These days distortion effects are an important part of various forms of guitar playing.
In the beginning, guitar amplifiers were used with electronic key boards and bass guitars. However, other guitars make use of a full range speaker system, as well as varying power levels to create broader bandwidth sounds. To be able to replicate low frequency pitches that are generated by electronic keyboards and bass guitars, you need higher amplifier power. This is especially true if you need high volumes of pitches. To replicate low frequency pitches, you also require a woofer or sub woofer that’s equipped to handle low frequencies. You also need a speaker cabinet that is intended to reproduce low frequencies. These speaker cabinets are required to be bigger and have a sturdier design and construction than those that are designed for high frequency or mid range sounds.