Krell Theater 7 XD 100-Watt 7-Channel Class-A Power Amplifier

Krell’s XD (Xtended Dynamics, Dimensionality & Detail) upgrade for the iBias amplifiers takes an already great sounding amplifier and raises its performance to the next level. XD is a classic example of Krell’s continuous R&D efforts reaping benefits across multiple product lines. During the development of the K-300i Integrated Amplifier we discovered substantial sonic improvements by lowering the output impedance below traditional norms. When applying this technique to our existing line of amplifiers, the improvement was so substantial, it deserved its own, unique designation—XD.

It was no simple matter merely lowering the output impedance. This affects the amplifier’s stability and transient response, so each stage prior to the output stage had to be re-tuned to work optimally with the lower output impedance. This lower output impedance exerts more control over the speaker drivers, and damps out unwanted vibrational modes—allowing a more accurate reproduction of the original signal

The “XD” upgrade for the Chorus/Duo/Solo amplifiers reduces the output impedance to less than half of its original value. This lower output impedance better damps unwanted speaker vibrational modes. Changing the output impedance also necessitated re-compensating each amplifier stage to achieve optimal critically damped transient response. This ensures that the amplifier accurately follows the dynamics of the input signal.

100-Watt 7-Channel Class-A Power Amplifier