Cyrus "Mono X" Power Amplifier
in silver (not quartz).
1 single monoblock Power Amplifier in silver (1 channel only - not a stereo pair).
Just recently returned from a service at the Cyrus factory.
Original RRP £1500.00
In Perfect Working Order.
In Good Condition (7/10) ~ excellent, except for the front right-hand & left-hand corners where its had a small knock - (see the 8th & 9th photos).
Comes with:- Instruction Manual, Mains Lead, Original Box & Packaging.
Power amplifiers at this level of performance are more usually behemoths of iron and unnecessarily flashy styling. The Mono X is a dynamic mono amp conservatively rated at 150 Watts. However the dynamic power of the amp is capable of burst output (such as occurs in all music programmes) of over 1500 watts.
This dynamic amplifier requires a very special design to successfully provide the immense power required for a system sound as close to the original performance as possible. The power and subtlety of the Mono X combine to make it one of the world’s most able hi-fi amplifiers.
The Mono X power amplifier is packed with a long list of features including the famous Cyrus ‘zero-feedback’ circuit topology (delivering outstanding power with exceptional load tolerance), a massive power supply with many stages of voltage regulation and a sophisticated computer control system offering intelligent circuit protection, convection control to maintain the temperature of the amplifier within safe limits and local bus communications with other Cyrus components.
• The harmonic distortion character of the Mono X is closely aligned to the response of the human ear. As output level reduces to lower levels where the ear becomes most sensitive to these effects, the distortion produced by the Mono X falls below measurable limits the result is exceptional musical resolution.
• Power amplifiers have two primary tasks - i.e. voltage and current amplification of the input signal, to provide a large and powerful signal for the loudspeaker. Traditionally, in most power amplifiers, these functions are combined into one overall circuit topology. The Mono X splits these functions into dedicated circuits - the input voltage gain amplifier and the output current amplifier. The voltage gain amplifier uses a zero feedback complementary bootstrap cascoded 'class A' buffer which drives a precision resistor. The current developed in driving the resistor is mirrored in to another precision resistor which is 52 times greater in resistance. The voltage developed across the second resistor is 52 times greater, hence voltage gain. This voltage gain operation is buffered by a second zero feedback complementary bootstrap cascoded 'class A' buffer. The current amplifier is an error corrected bipolar emitter follower designed to drive equally well into all impedances. In the Mono X neither of these stages have any global feedback. The current amplifier completely isolates the precision voltage amplifier from the loading effects of the speaker. This arrangement enables the Mono X to preserve fine detail, even under the most arduous of dynamic conditions.
Inputs - RCA phono or XLR balanced
Outputs - Twin BFA (bi-wire) connectors, RCA Chain out
Power Supply - 330VA Toroidal transformer
Communications - MC-Bus™ System Bus
Continuous Power - 150W (into 8 Ohms) 240W (into 4 Ohms)
Burst Peak Power - 1500W
Distortion - <0.004%, (1kHz into 8 Ohms) <0.05%, (20Hz-20kHz into 8 Ohms)
Frequency Response - -3 dB at 0.5Hz and 130kHz
Slew rate - 700V/µS (filters bypassed)
Max output Current - 80 Amps peak to peak
Sensitivity (RCA input) - 380mV (for 50W into 8 Ohms)
Sensitivity (RCA input) - 660mV (for 150W into 8 Ohms)
Sensitivity (BAL input) - 775mV (for 50W into 8 Ohms)
Sensitivity (BAL input) - 1.3V (for 150W into 8 Ohms)
Input impedance - 19Kohm (RCA), 20Kohm (BAL)
Chain Output voltage - 660mV (for 660mV RCA or 1.3V BAL input)
S/N Ratio - 114dBA
Dimensions - (H x W x D) 73 x 215 x 360 (mm)
Weight - 5.5kg