The JA120 builds on Jadis' tradition of combining fine hand craftsmanship with state-of-the-art innovation and design. This new amplifier is a is a push-pull monoblock pair which effortlessly cranks out 100 watts of pure class A power.
The JA120 uses the newer, more powerful KT120 output tubes and an additional front end tube which adds more gain to the driver circuit. This means the JA120 doesn't drive its tubes hard so the six output tubes comfortably deliver 100 watts. This new design offers the perfect blend of the big, bold, dynamic power of Jadis' world renowned JA200 with the immediacy and delicacy of their lower power JA30.
Of course the JA120 features Jadis' custom in-house, hand-wound output transformers which have been continuously refined and substantially improved since 2009. The output transformers, guaranteed for life, will accommodate speakers with impedance from 1 to 16 ohms.
Audio circuit protection is enhanced by new, easy to change, fuses. Other features include: pure point to point wiring, auto bias operation, oversized power transformer for better dissipation of heat and vibration, improved mechanical isolation, twin output terminals for bi-wiring, gold plated connectors, and a high grade, non-magnetic, stainless steel chassis which eliminates RF interference. The JA120 is a set of two mono amplifiers. Each amplifier measures 28" x 12" x 10" and weighs 99 lbs. Tube complement for each amp is: 6 KT120, 2 12AU7, 1 12AX7.
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You'll find no better or more tractable tool than the JA120. Big, heavy and pricey it may be, but it has power to spare and musical authority to burn. The trick is to deliver that, but to master subtlety and delicacy too - and that's where the 120s really score.
Roy Gregory, HiFi+, November 2012