Being the pinnacle of SA Lab transistor design White Knight SE integrated amplifier is a special version of the base model called White Knight, an audio component with truly unlimited potential. Phenomenal musicianship, fantastically high timbre and spatial resolution, ideal control of the whole dynamic range and the widest dynamic embrace — these are the main qualities of the White Knight. Similar to SA Lab Ligeia and Erato tube masterpieces, White Knight isn’t just a Top level audio component. It can be called a brilliantly sensitive instrument for penetration to the innermost of the Music.
Working on White Knight amplifier project, Alexei Syomin was guided by the idea that a transistor, unlike a tube, is meant for current amplification which helps achieve technical and sound harmony. Voltage amplification in White Knight is conducted by transformers that load thermostable modules. Therefore the task of voltage and current amplification is divided between different parts of the amp, each fulfilling its function the best way working in the most linear mode.
High quality iron from Japan enabled to manufacture high class coupling transformers corresponding to the transistor’s parameters. Transformers allow to quadruple voltage with minimal phase and non-linear distortion in the 5 Hz–250 kHz frequency range.
Unique constructive feature of SA Lab White Knight is the use of compounds with various heat conductibility for sustaining optimal and stable crystal or component temperature (50–55°) in conjunction with the lowest possible harmonic and intermodulation distortions. Mr. Syomin likens current modules to highly stable driving generators in an atomic clock. These modules are controlled current sources with voltage amplification coefficient close to 1. Specially for White Knight SE thermostable modules of feeding stabilizers were designed.
All stages are fed by stabilized sources (each one is fed separately). In the power supply Nichikon Muze and Rifa capacitors are installed, their total capacitance amounts to 450 000 μΩ. There are also separate transformers for the output stage (1200 W) and preliminary stage (350 W), for indicators (60 W) and volume control (60 W as well). White Knight produces up to 20 W of output power working in class A, while max power is 280 W and nominal power is about 260/130 W (4/8 Ω).
Input stage of the amplifier is a class A emitter repeater working on a transformer. Then there is a more powerful driver working on a transformer too; the output stage is another emitter repeater. The output transistors are Motorola MJ15025, tree in each shoulder.
Stabilized power supply with specially designed thermostable module is also realized on Motorola devices. There is no general negative feedback here. SA Lab White Knight’s weight is huge (more than 70 kilos) mostly because of numerous transformers.
Alexei Syomin started tuning the sound from the output stage, bearing in mind that alterations must not change the character of sound. All transformers were assembled by hand from Japanese iron. Transistors in all stages are of the same type. In the preliminary stages Riken Ohm resistors are used but in the output stage driver more powerful Kiwame resistors are used. The mode is set by AudioCore of 100 W total power.
The amp has no printed boards — the engineer preferred point-to-point wiring which considerably complicated workings with compounds that prove optimal temperature modes: it wasn’t easy to insure non-leakage.
Front knob (the only control organ of White Knight) combines three functions: volume control (made with resistive chains), input selector (press and turn) and on/off switch (press and hold for 2-2 sec).
The cabinet of White Knight is manufactured by means of profile tooling of multi-layered plywood sandwich (as standard; it can be manufactured from exotic wood massif).
Output power (max) 4/8 Ω, W – 280/140 x 2
Frequency range (–0,3 dB), Hz – 5—250 000
Harmonic/Intermodulation distortions (1 kHz, 1 W), % – 0,0005/0,0006
Signal/noise ratio (non-weighed), dB – 120
Dumping factor – 950
Audio inputs – 4 x RCA
Linear input – RCA
Power consumption (no input signal), W – 150
Dimensions, mm – 580 x 440 x 500
Weight, kg – 70