Senior Design Team sdmay18-39 • Sound Effect Devices for Musicians
In the audio amplification world, particularly with respect to electric guitar signal amplification, musicians have historically chosen to use amplifiers driven by vacuum tube technology. Up until around the 1970s, vacuum tubes dominated the audio market, and many of the ‘classic’ rock albums that listeners hold in high esteem are recordings of vacuum-tube drive amplifiers. The sonic footprint these albums left on the modern musician is considerable, and many guitarists refuse to perform with amplifiers driven by tube alternatives – the dominant alternative being the BJT solid state amplifier – solely because of the ‘classic’ tones associated with vacuum tubes.
There are significant advantages to utilizing solid state technology for guitar amplification. Solid state devices are significantly more power efficient than vacuum tubes, and the physical footprint of BJTs are magnitudes of order less than that of vacuum tubes. Additionally, solid state technology is far more resilient to abuse – both physical and electrical – than tubes. Perhaps most importantly, BJTs are significantly less expensive than vacuum tubes.
Despite the advances made in BJT technology (in efforts to model the tube amplifier) and the considerable financial benefit to producing solid state amplifiers on a commercial scale, solid state technology still, for the most part, is undervalued to vacuum tubes amongst professional musicians. The team believes this is largely due to a failure to properly address the sonic aesthetics surrounding vacuum tube amplifiers.
The team believes that, if the key musical parameters around the tube amplifier are quantitatively observed, a tube ‘effect’ can be modelled and reproduced. In the proposed solution, the team designs an emulator that can impose vacuum tube amplifier characteristics onto the incoming guitar signal. The solution offers an all-in-one module that addresses the tone demands of guitarists while maintaining a comparatively less convoluted and expensive package compared to the boutique vacuum tube amplifier.