The design employs PUSH-PULL configuration operating in class AB, based on original Mullard design with 2 X EL34 Valves per channel. The input stage has optional cathode follower which we highly recommend for people who do not already have one. This is followed by EF86 input stage which is a Pentode, this is done to reduce the effect of stray miller capacitance inherently present in triodes. The Miller capacitance of a pentode stage is normally only about 1/10 of that of a triode stage with the same gain.
Choice of Components
Audiophile grade capacitors & high-precision Metal Film resistors with double power rating and tight tolerances as per military/space-grade standards are employed for robust, precise & consistent operation and low thermal noise.
The critical Cathode bias & Anode Resistors are Non-magnetic, non-inductive, all welded construction which greatly enhances frequency response. Combined with Aryton-Perry winding inductive reactance and signal loss are almost totally eliminated. These components Meet or exceed the specifications in the military standard MIL-PRF-26/MIL-STD-202 for wirewound resistors.
The grid resistors are also chosen to be of extra tolerance and Military rating. 1% precise, Dale resistors with Military rating MIL-PRF-18546 has been deployed for lifelong consistency & precision. These are also made using non-inductive (Ayrton-Perry) winding technique.
The model nameCB1070i is a tribute to Mr. Claus Byrith who mentored & supported us in improving the classic Mullard design further.
The output stage is operated in standard Ultra-Linear configuration.
The outer chassis is made of teak-wood CNC Drilled and hand-finished for a royal look & appeal. The inside rear of the Amplifier houses all transformers ( Custom Toroidals for HV & Heater and 2 Output Transformers) and is well shielded & Ventilated by perforated steel sheet.
Controls
- Volume control for each channel
Circuit Highlights
The entire circuit follows distributed star grounding methodology. Signal cables are PTFE insulated & shielded, orientations of cables & transformers are carefully done to minimize interferences.
An optional cutting edge control system based adaptive & dynamic automatic bias mechanism for absolute precision in the valve pairs leading to significant reduction in distortion & superior stereo imaging & clarity of soundstage & low end dynamics.
Read more about this technology HERE.
Specifications
- Power Tubes: Matched Quad of EL34, Hand Selected
- Preamp Tubes
- 2 EF86, NOS Mullard, Made in Great Britain, (1 per channel)
- 1 ECC82/12AU7, Optional Buffer, (1 Triode Section per channel)
- 2 ECC83/12AX7, Phase Splitter, (1 per channel)
- 1 Power Transformer, Toroidal
- 1 Heater Supply Transformer, Toroidal
- 2 OutPut Transformers
- Biased to Deliver 60W Output Power