Audio preamplifier circuitry is increasingly used in electric guitars and electric bass guitars. A general preference for circuits built using discrete solid state components vs integrated circuit operational amplifiers appears to be building within the user community for these instruments. A double blind experiment was conducted to determine if users showed a preference between a JFET discrete component preamp and an opamp preamp following a listening evaluation. Results indicate no clear preference for either type.
Mottola, R.M. "A Listening Evaluation of Discrete vs Integrated Circuit Audio Preamplifiers in Stringed Musical Instruments", Journal of Musical Instrument Technology #23, 2003
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