NAGRA CLASSIC PREAMP

The DesignFully complementary design based around a precision input stage maintains perfect balance between the positive and negative components of the signal. Any distortion artifacts that appear on one half of the signal will also appear on the other half, and thus cancel each other. Gain circuits operate in the current domain, assuring the amplifier’s performance does not fluctuate, regardless of the speaker demand. New input stage devices deliver a 300% increase in current as compared to the previous devices. These wider-bandwidth, higher-power components extend low- and high-frequency performance with reduced distortion in both frequency extremes. Global negative feedback is not required, as the amplifier’s open-loop linearity eliminates the need for this performance-robbing technique.

A new bias stability circuit in the driver stage provides a nearly 50% increase in operating bias. Increasing Class A operation directly correlates to better sound quality. With this new circuit topology and the unique copper/aluminum heatsinks, thermal issues become irrelevant, the new scheme ensuring bias consistency, preventing excessive temperatures even under the greatest demand.

A critical element of any amplifier output topology is the driver section. In the Relentless 800, the driver transistor has been upgraded to handle 33% more power per device. Additionally, the driver transistor count has doubled, minimizing demand on each
individual device and lowering overall amplifier output impedance without resorting to global negative feedback. Individual transistors are used for the positive and negative signal elements in a complementary arrangement, nearly doubling the current drive
necessary to maximize the enhanced output stage that follows.