Biasing the tubes was the last step and that was very simple. There are easy to access bias points on the chassis and Manley even supplies a voltage meter.  I biased each 300B to the specified values in the manual, and was off and running. It was that easy. I should mention I used the supplied stock power cords for about a week then swapped them out. Special mention must go to the Audience powerChord e, which I really felt had a great synergy with the Manleys. It clearly lowered the noise floor and improved dynamics.

The review samples were burned in at the factory for over a hundred hours and they were ready to shine right out of the box. My initial impression was one of sheer amazement at the immediacy and the beauty of the sound. It was easy to see why the SET amp has had such a long and loyal following, despite some practical shortcomings. I then spent quite a bit of time switching between Single Ended mode and Push-Pull. With both the Audience and Harbeth speakers I generally preferred Single Ended. I just felt the sound was a bit more open and immediate - and in my small listening room, power was never an issue. Not once did I find myself feeling deprived of volume or dynamics. The fact that both the Harbeth and Audience speakers are pretty easy to drive also made a difference.

I decided to put the 300B’s through their paces with a variety of music, both small and large in scale. First up was Seal’s 2007 electro pop flavored System. It is a big sounding record, with heavy bass lines, techno flavored beats, and Seal’s husky voice riding on top. What makes the album even more interesting is the use of acoustic guitar, and other natural touches on an album with an overall electronic feel. But Seal’s vocals are beautifully recorded and the whole thing is not a victim of the compression wars. Quite the contrary. Through the Manley amps, the album sounded as big and as intimate as I have ever heard it, even on way bigger amps. I was hooked.

Legendary British guitarist Bert Jansch’s 2000 “comeback” album, Crimson Moon, is filled with very nicely recorded, intricate guitar work and Jansch’s trademark slurry vocals.  Acoustic guitars were woody in tone, and the overall ambiance was stunningly lifelike. Clearly there was some serious tube magic at work here.

I have some final notes on settings and overall preferences With the Audience 2 + 2 monitors I preferred Single Ended mode with zero feedback. It just clicked. With the Harbeth’s I preferred Single Ended 80% of the time, with between 5 dB and 7 dB of feedback, and Push-Pull with zero feedback 20% of time. As Manley said, your preferred settings will strongly depend on your room and speaker set up.