Papworth M100 Monoblock Amplifiers

Here we have a nice pair of monoblock power amplifiers from British company Papworth. They are classically styled valve amplifiers that come in good fully working condition in original factory packaging along with manual plus our regular three month warranty.
Papworth Say….
The feedback circuit in any amplifier determines many of that amplifier’s characteristics. For “simple circuit” designs of tube amplifiers it is usual to take feedback from the secondary windings of the output transformer. The feedback characteristics can therefore be altered by a complex loudspeaker impedance connected to that amplifier and the performance of that amplifier will be changed as a result.
This is the main reason why so many amplifiers are unable to drive loudspeakers with complex impedances to listenable levels without degradation of sound quality.
With the McIntosh Circuit design from Papworth Audio Technology there is no feedback taken from the secondary windings of the output transformer. Put simply, this means that the amplifier will drive any loudspeaker without its own performance characteristics being affected by the loudspeaker impedance.
All Papworth Audio Technology Power Amplifiers have highly developed McIntosh Circuitry and it is therefore quite possible to drive loudspeakers with complex impedances and low efficiency with perfectly satisfactory results.
All of our products are hand built, and individually tested with a care and detail seldom seen in the todays world of mass production. These products are made at our workshop in Cambridge England
The tube monoblock are made with chassis and transformer covers formed from two millimetre thick hand polished stainless steel. Front panel logo plates are pure gold plated, and laser etched for the finest appearance. Safety covers, legend plates, and base plates are rust protected and painted in black silk finish.
M100 Uses two pairs of EL34 pentodes to deliver over 120 Watts RMS into 8 ohm or 4 ohms. This amplifier has been in continuous production for almost twenty years. The current production model is wired in many critical areas with multistrand silver plate cables, and fitted with WBT full specification loudspeaker terminals. The four large British BHC electrolytic storage capacitors have a total capacity of 2800 microfarads for excellent transient response. The custom wound mains transformer is rated at 400 VA for a long and trouble free life. Our output transformer, also 400 VA, is sectional wound with eleven separate sections to achieve a very low leakage reactance. This allows a flat response from 14 Hz to over 30 kHz, with a deviation of less than plus and minus 0.2 dB. At 100 Watts rms output it achieves better than 0.18% total harmonic distortion.
Specifications:
Power Output: 100 W RMS
Frequency Response: 14 Hz – 30 kHz (± 0.2 dB)
Signal to noise ratio: – 95 dB
Total Harmonic Distortion: < 0.18 % at 1 kHz, 100 W
Input Sensitivity: 650 mV
Output Impedance: 4, 8 or I6 ohm
Tube complement: 4 x EL34; 3 x ECC83; 1 x 12BH7
Dimensions: 250 (W) x 380 (D) x 170 (H) mm
Weight: 21 kg