The holy grail – that is our meaning of Silver Bullet – is the solution to a seemingly insurmountable problem in amplifier design: the transformerless amplifier (OTL). The transformerless circuit concept is so good because it allows absolute precision and speed and yet so difficult to execute, because it is so complex and expensive in practical applications. This circuit, when properly implemented provides the most brilliant results; but because it is so complicated and complex, it is also very rarely found in home audio amplifiers.
Having gained 12 years of relevant experience designing and manufacturing these extremely complex and expensive OTL (Output TransformerLess: a tube amplifier without the usual sound limiting output transformer) tube amplifiers, we have yet again completely revised and significantly improved upon our unique OTL amplifier design. With EINSTEIN’s The Silver Bullet OTL we have perfected this highly demanding, yet sonically undisputed concept to new levels of refinement.
The original concept of The Final Cut OTL amplifier has been carefully preserved by us, as only this complicated circuit design ensures ultra-fast signal paths, linear phase and realistic, EINSTEIN typical playback performance.
An OTL amplifier has, at its core advantage when compared to a conventional tube amplifier with output transformers, the ability to connect a loudspeaker directly to the output tubes. The sound quality limiting (and technical measured performance) output transformer does not interfere with the circuit. Frequency response, bandwidth, and phase linearity are in true OTL principle far superior and thus the typical EINSTEIN sound is achieved via our design philosophy of offering ultra-fast, high bandwidth, linear phase, resulting in unsurpassed sound quality. Without the output transformer in the signal path, the amplifier controls the loudspeaker with absolute authority: you simply can not produce better sounding music.
The damping factor of the EINSTEIN The Silver Bullet OTL amplifier is at a minimum a factor 5 or higher compared to a conventional tube amplifier or even in other OTL realized concepts. The only real disadvantage of an OTL amplifier lies in its incredibly complex circuit which results in very expensive manufacturing techniques.
The EINSTEIN The Silver Bullet OTL is a quite typical EINSTEIN design, offering a fully symmetrical circuit design, making a best possible signal to noise ratio a guarantee. Even numbered distortions, which have adverse affects on sound quality, are simply not part of this type of circuit and therefore the signal remains pure and free from any such distortion interference. These are the same principles as with our other audio components, The Preamp and The Source. True to the concept of a wire with gain coupled with the shortest signal paths, the amplifier stages are reduced to only the most necessary. The Class A PPP stage (parallel push-pull output stage) was conceived as the optimal choice providing operating points with high current and exemplary linearity with incredible bandwidth. Sound degrading crossover distortion simply doesn’t occur and by galvanically coupling the loudspeaker, exemplary bass performance, down to the lowest registers, can be reached.
As with The Preamp, an extremely capable power supply is required to maintain the stability of these innovative circuits. By utilizing filtering and current source circuits, all supply voltages remain absolutely clean and constant over a wide bandwidth. Thus, even mains fluctuations are no longer a deterrent to the overall sound quality of our OTL design.
An EINSTEIN exclusively developed control technology allows us to utilize an OTL circuit 100 % with all of the sonic advantages this circuit topology harbors. There is no relay in signal path to the loudspeaker; the loudspeaker is directly coupled to the output tubes, yet remains 100% protected from any tube defects or issues. This results in an exemplary damping factor over the entire audio range, low distortion values and a dynamic behavior that can easily handle even the fastest signal transients . This is what we call “useful dynamic” at any volume level, with no compression or artifacts. In conjunction with our new The Preamp, our new OTL is a music player entering an entirely new dimension – absolutely realistic and emotionally charged audio magic!
Signal to noise ratio greater than 98 dB
Distortion at 1 KHz less 0.02%
Output power 80 W/12 Ohm , 65 W / 8 ohms (45 W / 4 Ohm)
Damping factor greater than 95/8 ohms
Weight 30 kg / Mono Amplifier
Dimensions (H x W x D) 24 cm x 43 cm x 49 cm