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Re-introducing the undisputed champion in price, weight, and performance: the $35,000, one-hundred pound, Fairchild 660.
Avid’s no-compromise replica captures every detail of this studio classic.
Designed in the early 1950s, the Fairchild 660 is a variable-mu tube limiter. Variable-mu designs use an unusual form of vacuum tube that is capable of changing its gain dynamically.
The result? In addition to featuring a tube audio stage like the LA-2A, the Fairchild actually achieves gain reduction through the use of tubes!
The heart of the Fairchild limiter—a 6386 triode—is one such variable-mu tube. In fact, four of these tubes are used in parallel. A key part of the Fairchild design, it ensures that the output doesn’t get darker as the unit goes further into gain reduction, and also reduces distortion as the tubes are biased further into Class-B operation.
