Technics SU-V85A Amplifier
This model SU-V85A fully deserves the battleship connotation and, sadly to my mind, the front panel is made unnecessarily busy with a mess of boast words. However the controls are well laid out and clearly if repetitively marked. For example, is it necessary to state that the knobs marked Bass and Treble are tone controls and that + 10dB and - 10dB max and min? All the control with the possible exception of the CD Direct switch (bypassing the input switching and taking the CD input straight to the volume control) have the usual feel of good Japanese quality, and nowhere is this more true than in the group of dual purpose microswitches which command the electronic input and record selectors. The left-hand button is labelled Rec(ord) Mode and can be made to sequence through three stages as indicated by the red LED above it. When this is extinguished, any of the seven adjacent input source selector buttons will pass that desired signal, now shown by a light above it, to both the amplifier and the recording outlets. A touch of the Rec mode button starts its LED flashing, and in this condition the seven input buttons will select only the recording sound source and the selection is marked by a second light. A further touch and the Rec mode LED stays illuminated allowing the source being auditioned to be changed whilst not affecting any recording that may be in progress from any or the sources. A very versatile arrangement.
Large letters on a raised label proclaim that this is a "Class AA VC4 amplifier system". What does it mean? Basically that this is yet another variant on Quad's 'Current Dumper' principle first seen in practice in the 1975 Quad Model 405. The basic idea is pleasingly simple to understand. Each channel's output is the resultant of two amplifiers, a small low-key voltage control amplifier which decides the quality and a hefty current amplifier which adds the beef. Hence V(oltage), C(urrent) and 4 amplifiers = VC4. All the ways of making this clever idea work are based on some form of 'error bridge'; this one requiring the use of complementary pairs of current supply transistors clamped to a generous 'heat sink located under the ventilation slots in the cover. Be very careful not to cover them with anything. The other major component under the bonnet is the mains transformer, everything you would expect of such a powerful piece o f equipment and accounting for a major part of the weight. It is bolted down on to a rubber pad, presumably to avoid transfer of mechanical hum to the casework. The power amplifier components are on a single printed-circuit board fitted alongside the heat sink so that the leads of the plastics encapsulated current transistors drop straight into it. Other sections of the circuit have their own boards situated adjacent to them. This form of construction leads to a fair amount of internal wiring, much of it in the form of ribbon cabling, but it is all very tidily done.
Four small buttons on the front panel engage loudness a 20dB mute, select Moving-magnet or Moving-coil pickup matching (the latter not really adequate for the very low output types) and the fourth is 'labelled' Tape 3 mon/ext'. What this does is to disconnect the pre-amplifier section from the power amplifiers, permitting the insertion in the chain of all sorts of gadgetry; graphic equalizers, KEF Kubes, AV surround sound, or even the third tape machine with monitoring facilities which the title suggests. Beware of it for, if nothing is connected to the two pairs of Phono sockets it normally links, then there will be a deathly hush and you may well decide that your beautiful battleship has sunk. Nothing warns you - no coloured light-and the button is so small you won't notice it has become depressed. I t has caught me out and, I have suggested to Technics that some form of removable link should be included across those sockets to avoid that sinking feeling.
My few quibbles apart, this is a delightful amplifier to use and the clever recording selector arrangement soon becomes second nature. Just now and again I detected a faint click as the recording selector dropped on or off the source being listened to, but this was a one-way thing and no clicks appeared on the recordings. This is a very neutral amplifier, adding to or taking away little or nothing of the signals presented to it. The available power means that under normal domestic conditions it is never going to be strained and the overall impression one gains is of alertness and confidence. When called upon, it will perform adequately for the noisiest party and it never blinked when asked to provide disco volume for a whole evening.
Technics have done well with this design and, although I am sure we shall be hearing other excellent designs from other stables, this SU-V85A is something of a landmark for a mass-produced piece of audio equipment. I would certainly be happy to use it and, during the time I have been doing so, felt quite free of the desire to revert to my reference gear 'just in case'; and that does not happen often.
