We'll never forget the impact the introduction of the Marantz Model 7 and Model 9 had in the industry more than 40 years ago. These models fused original circuit design with rational thinking and aesthetic appeal. Not only did these models help establish the Marantz name and brand in the audio world, but also influenced the direction that audio evolution has taken ever since. That the Model 7 and Model 9 are still sought after-components is a testament to the fact that even though musical sources may have changed, thoughtful design and engineering continue to endure defying the laws of music and audio history. Reviving these two numbers will enrich audio history again. The distinctive voice of the Model 9 has been reborn in the monaural power amplifier MA-9S1. Now it is time for the Series 2 version to update with the latest experiences Marantz engineers made and the use of new material and components to further excel the indescribable performance of this monaural power amplifier.