Designing a New Speaker
This article explores the history of guitar speakers, their components, and their impact on musicians and audiences.
Eminent Technology's Model Twenty introduces significant advancements in driver design, revolutionizing a field stagnant for 70 years.
A look into the past
During the 1930s and 1940s Big Band Era, guitars were mainly rhythm instruments, overshadowed by louder brass, drums, and piano. Charlie Christian revolutionized this by using pickups on his Gibson guitars, allowing amplification. Post-WWII, Big Bands declined, impacting musician employment.
Les Paul's introduction of the solid-body guitar, like his "log" guitar, reduced feedback issues common with the amplified hollow body Gibsons (denoted "ES" for Electric Spanish). Amplifiers, originally modest radio outputs, grew in power, making feedback a bigger problem.
Early guitar amps relied on existing technology, using cone drivers from console radios like Zenith and RCA. These were typically 12-inch drivers from larger home or commercial units.
The 12 Inch Speaker
Radios were designed for AM radio's limited bandwidth, not for guitar tones, leading to missing high frequencies. Despite advancements, manufacturers still use traditional 12-inch cone drivers, a standard for over 60 years. Even renowned makers like JBL and Celestion, originally producing for console radios, haven't significantly deviated from this design, merely enhancing magnets and suspensions. These speakers are efficient but heavy, adding to musicians' load. The Eminent Technology Twenty addresses these limitations of 12-inch cone speakers.
ET's study focused on guitar signal characteristics, including pickup and amplifier frequency responses, speaker directivity, power handling, and distortion. Electric guitar pickups have a usable range of 80 Hz to 6 kHz, with 80-90 dB dynamic range and low noise. Finger-plucked strings produce fundamental frequencies and overtones, with even-numbered overtones preferred over odd-numbered ones. Different guitars, like Gibson Les Paul and Fender Stratocaster, produce distinct sounds. Pick-plucking enhances fundamental tones and complex overtones, while amplifier frequency responses vary across brands like Fender, Marshall, and Vox. Amplifier overdrive and tone controls significantly affect sound. Guitar speaker efficiency is high, with responses varying based on orientation and position. Speaker distortion and impedance influence sound quality, with typical guitar speakers showing limitations compared to innovative models like the Model Twenty, which offers improved frequency response, lower distortion, and uniform sound projection. This analysis highlights areas for improvement in guitar speaker design for enhanced user and audience experience.