Å lodde sammen en forsterker er noe annet enn å
konstruere legender.
Around 1980, two extraordinary solid-state amplifiers appeared in the high-end audio market. John Iverson offered the Electro Research A-75 and Andy Rappaport offered the Rappaport AMP-1. Both of these were 40-volt (75 watt per channel) amplifiers with temperature tradeoffs in their design. The A-75 had a noisy fan and the AMP-1 ran egg-frying hot. And these amplifiers changed the picture of hifi by presenting a musical signal with more range, more detail, more texture, more space, and more music than the previous generation of top tube amplifiers. These two amplifiers were an interesting contrast in design and measurement. The A-75 was a high-feedback design with something like 0.0005% THD while the AMP-1 was a no-feedback design with 0.5% THD at half-power in the high frequency range. Both amps, however, were articulate in their reproduction of music. Mark Levinson made some superlative solid-state amplifiers, but not in this league. And Jim Bongiorno offered the Sumo amplifiers which were
Da må en tenke utenfor A4 formatet,som Richard Dunn,muligens den beste forsterker jeg har erfart.
The Integrated Statement.
https://www.nvahifi.co.uk/richard-dunn-interview/
The way I design my products is to use the simplest circuit possible, and make the most of it, and make a good product that the customer can buy at a reasonable price.
We never planned to make a universal or unconditionally stable amplifier.
Anybody can design these ...
so we must set the conditions under which the amplifiers will work comfortably, although this may not be conventional. As far as amplifiers are concerned, convention stresses stability, and the more stable the better.
Q: Conventional amplifier designers must have their reasons, mustn't they?
A: Maybe they just want to follow convention. You know, there is a broadcast university in the UK called The Open University.
They teach electronics and they use the conventional electronic circuit structures for their text materials. All those that take the course are taught to make stability their priority and there is no mention of sound quality!! So it is rare to find a designer or electronic technician who will think that their test equipment is wrong when what they hear contradicts. They just depend on and trust their oscilloscopes and distortion analysers. If you were to judge NVA amplifiers by these criteria you would say they are not very good, but if you listen it is a completely different story. Test equipment readings have virtually nothing to do with the musical ability of an amplifier.