icon Audio MB90 MK II Instruction Manual

icon Audio MB90 MK II Instruction Manual Manual pdf 1 page image

Page 1icon AudioInstruction Manual Covering:MB90 MK II Mono BlockAmplifiersShown with KT120 output valvesContents1 Introduction & Final Inspection2 Quick Set Up Guide3 Connecting inputs & outputs4 Getting the best performance5 Trouble Shooting6 Bias Adjustment7 Valve Replacement8 Specifications9 Guarantee10 Packing Instructions1 IntroductionThank you for purchasing theMB 90s. Thesepure valve mono block amplifiers are the result ofyears of careful design and listening tests with a hugerange of speakers. The amplifiers are hand built usingcarefully selected audiophile components. Thetransformers are hand would using low oxygen copperand special Japanese long grain iron. Finally eachamplifier is valved, carefully commissioned andtweaked for best performance in Leicester UK.In order to get the best out of your amplifier, pleaseread the enclosed notes. Even if you are experiencedwith hi fi please read the ‘quick set up guide’.Should you be uncertain about anything please contactyour dealer or us for advice.Valve amplifiers do need a little more attention thantheir solid-state counterparts, but the sonic results aremore than worth it. In this manual we have tried toinclude everything that you need to know. Please letus know if you find any errors or feel that we havemissed anything out.Hi fi reproduction is a long chain of events thatincludes the recording, editing, mixing etc, beforebeing transferred to a medium such as LP, Digital, etc,before being played through your own source unit, theamplifier and finally loudspeakers.Your room acoustics will affect the sound before itfinally reaches your ear. Whilst the amplifier isarguably the most important part of a system, it isimportant to remember that the weakest link willalways affect the final results. And not all recordingsare ‘equal’! Therefore a good amplifier will alsoreproduce recording imperfections. Therefore settingup and testing should be made with a ‘clean’ wellbalanced recording.TheMB 90 is a push-pull Ultralinear stereopower amp, capable of running in either Ultralinear(half pentode and half triode) or pure triode mode,using the excellent KT120 or KT88 valves. These arein fixed-bias mode which gives maximum power, coolrunning and even indicates valve condition. You willoccasionally need to check the bias. The driver andphase splitting is all triode for best sound quality andlow noise. They are sensitive enough to be used withall modern source equipment. Their simplicity coupledwith point to point hand wiring without the use ofprinted circuit boards results in an open euphoricsound that is wonderfully detailed and warm. The reference to KT120s should be taken read whatever output valves your amplifier was suppliedwith from Icon Audio, e.g. KT88/KT90/6550 see note 7 page 8.