The C1 control unit is an ultra low-noise line stage with an unprecedented noise floor, despite the fact that it employs vacuum tubes. A key part of that performance is the unit’s gain structure. The C1 barely attenuates incoming signals and so minimizes the amount of gain required and the residual noise added to the signal – a simple but incredibly effective solution.
Elimination Of AC Circuitry
The biggest source of self-noise in a conventional amplifier is the AC supply, both the incoming signal itself and the massive transformers and power supply components necessary to handle it. Siltech eliminated this problem by making the line-stage and separate V1 voltage gain stage battery powered, using sophisticated rechargeable cells to drive specially selected low-noise tubes. The results combine the remarkably linear voltage gain of vacuum tubes with the ghostly quiet background of a pure DC supply.
The Apollo Light Drive
Batteries are simply not capable of delivering sufficient current for a genuinely powerful and load-tolerant amplifier – both critical contributors to maintaining dynamic range and headroom. But a conventional AC supply was deemed unacceptable due to the problems of associated noise and AC pollution. Siltech’s solution was typically innovative and bold: the Apollo Light Drive. An incredibly powerful light source is used to drive a photo-electric cell, that generates DC for the amplifier’s output stage – galvanically isolating and totally decoupling the current gain stage from the AC supply. Conceptually simple the engineering involved was extremely challenging but the results are revelatory.
The SAGA System
Used together, the three elements in the SAGA system (the C1, V1 and P1) are capable of delivering remarkable performance, including a maximum dynamic range of 145dB! The system is clean enough and quiet enough that micro-dynamics and low-level detail can be clearly defined and heard, yet massive dynamic demands are met without hesitation by the conservatively rated power amplification. You won’t ever have heard an amp this fast, this clean, this clear, this natural or this invisible. In fact, it’s easier to say that you’ll never have heard an amp this musical. By stripping away the low-level veiling and dynamic compression that limits the performance of other, conventional amplifiers, SAGA reveals the performances that are really on your recordings – allowing you to really hear them for the first time.
“Beautifully built, superbly finished, stylish and conceptually elegant, the Siltech S.A.G.A. introduces a novel topology, mixes established and cutting-edge technology and does it in a genuinely cost no object, no compromise form. The engineering is beyond reproach, the company extremely well established and they’ve applied every last ounce of their accumulated knowledge to this problem. The result is a genuine step-change in performance, a level of sonic invisibility that I’ve never experienced before…”
Roy Gregory, TheAudioBeat.com – Product of The Year 2013