Laboratory Series Preamplifier and 200wpc Power Amplifier

We are not happy, as many are, to merely to separate the preamplifier from the power amplifier of our Integrated Amplifier and box them individually. We do make two power amplifiers of which one is the same as in the Integrated but the other is completely different and sounds a great deal better, it more than justifies the additional cost of a pre/power combination.

The Preamplifier has six inputs and matches the appearance the rest of the range. However it is a more versatile and has much better sound quality. This is achieved by the use of special low noise transistors in the input stage driving a discrete Class A output stage. This not only gives exceptionally good distortion and signal to noise figures but also guarantees a lovely warm and natural sound; most important with really revealing systems. There is also a great deal of headroom and plenty of current to drive long leads if they are needed.

A good circuit can be ruined by bad layout (hence the differences in sounds between so many CD players) but ours is neat and very elegant with extremely short signal path routings. Switching is by reed relay and volume by motorised Alps, an arrangement that has dramatic advantages over most solid-state alternatives.

This preamplifier has been designed to drive our new, high performance, stereo power amplifier and to ensure that the substantial improvement in sound quality that it produces is clearly audible. Used with the S21 MA V2.0 215 wpc Amplifier there is a dramatic improvement over the Integrated Amplifier and this is a more versatile system.

The present 200 wpc type S21MA stereo power will continue to be available but we recommend the V 2.0 for either the Brios or Trios.

The new S21MA V2.0

It had been our original intention to offer bridged versions of the stereo power amp, they would have had over 500 watts output and were to be sold as Monoblocs. However, things are never as straightforward as they seem. Increasing the output of the Integrated amplifier to 200 wpc had produced a dramatic improvement in sound quality because it reduced clipping significantly but increasing the power to 500 watts made no audible difference, in fact it sounded slightly worse because of artefacts that occur in bridged designs. We decided that a much higher quality power amplifier was needed so that even bridged; it would sound better than the Integrated. The result was large and very expensive and in stereo form it sounded incredibly good. Bridging it still did not appear to give any benefit. And, by now it, was clear that most customers were using speakers that could, by being overdriven, be damaged by 200 watts, never mind 500! Sound quality was more important than power and the Brios worked perfectly with the smaller amp although they would take more than double its power.

In its original form this new stereo power amplifier would have cost twice as much as the Integrated amplifier and a preamplifier was needed too. Experience shows that it is necessary to sell and manufacturer in quantity if quality and reliability are to be maintained. Anyone who has experienced “High End” equipment will tell you that it can be extremely unreliable, as though the owner is doing the development work! Therefore it was decided to do a complete re-design to produce the same performance as this new prototype but in the same enclosure as the present stereo power amp so that it could sell for a similar price.

The development process has taken eighteen months but the result is a triumph. The new V2.0 power amplifier produces 215 wpc and differs from conventional amplifiers in that its distortion remains almost non-existent a low power levels. Normally distortion should be considered as a percentage of full power so that at low levels it becomes a significant proportion of the power being produced, this is not the case with ours and it means a fairly dramatic improvement in sound quality over the hugely successful Integrated Amplifier. Consider the present model, the number of awards it has received, its sales success and how highly it is rated by those who’ve tried it and then try to imagine a very obvious improvement because that is what it is.