Harman Kardon CIT25 Owners Manual - Page 4

I n t r o du c t i o n Important Design Features of Citation 25 Remote Control Preamplifier Thank you for choosing Citation. Judging from your choice of preamplifiers, you are a discriminating music listener. You now own a superb piece of high fidelity equipment with the additional capabilities of true video switching and dubbing. Used properly, you are about to begin thousands of hours of music and video enjoyment. While you are probably no beginner when it comes to high fidelity components, we nevertheless ask you to read and carefully follow the instructions in this manual, to insure a successful partnership between you and your new Citation Remote Control Preamplifier. Actual hook-up instructions begin on page 10. ifietrOf 00110 Musical waveforms are comprised of positive and negative polarity portions which must he amplified in precisely the same way. Unlike traditional designs which use two semiconductors in a non-synimetrical configuration (demanding excessive amounts of feedback correction and causing a musical distortion) the Citation 25 employs fully symmetrical circuitry. While this approach requires considerably more overall circuitry, it is based on the most fundamental principles of amplification and represents the purest way to achieve gain. Feedback correction is minimized and complex musical waveforms are reproduced flawlessly. Wide, - Oanditii eg0Itlit In the Citation 25, care has been taken to not employ circuit design that reduces Total Harmonic Distortion at the price of compromising overall sound quality. This compromise often occurs when a preamplifier is designed with very high gain, narrow bandwidth and high THD through application of a large amount of negative feedback. While gain and TIID are reduced and bandwidth does get somewhat wider, a fearful price is exacted in amplifier reaction time. When a circuit is slow to react to instantaneous musical impulses, miscorrelation occurs between the incoming signal and the applied feedback. Unlike THD, miscorrelation distortion follows the topology of dynamic musical waveforms and is VERY audible as a brittle artificiality which constricts the sound stage, limits the natural transient attack of many instruments and contributes to an overall fatiguing listening experience. Harman Kardon engineers did not take this "easy way out", Your Citation 25 was rigorously designed from the very beginning for inherently lower gain, low Total Harmonic Distortion and very wide open-loop bandwidth. Judicious application of minimal negative feedback produces still wider bandwidth and even lower THD. Another benefit of the Citation 25's wide open-loop approach is precise correlation of incoming music signals to any necessary low level negative feedback, resulting in extremely fast amplifier reaction time. You will hear the difference in the crisp transient response and increased ability to reproduce delicate musical overtones. isseTii#044000s$,Cii:Oliitr In designing your Citation 25, Harman Kardon engineers discovered that, contrary to the half-century-old research of Fletcher and Munson, high end equalization was not necessary for the perception of increased bandwidth at low sound pressure levels. Rather, a fixed amount of low frequency boost was preferable. Also correction for midrange phase errors inherent in low frequency loudness equalization made a dramatic improvement in overall sound quality. It is this rigorous attention to phase accuracy which sets the I Jarman Kardon Phase Correct Loudness circuit apart from conventional controls. Lower frequencies will simply sound natural, with no coloration or degradation of stereo imaging. The effect