At CES 2014 Krell ups the ante with new tech audiophile amplifiers

Krell has always represented the best of American high-end audio, at CES 2014 it's showing a new line of "green" power amplifiers.

Steve Guttenberg
Ex-movie theater projectionist Steve Guttenberg has also worked as a high-end audio salesman, and as a record producer. Steve currently reviews audio products for CNET and works as a freelance writer for Stereophile.
Steve Guttenberg
2 min read

Founded in 1980, Krell Industries' amplifiers have long set the benchmark for sound quality, and at CES 2014 the company took the wraps off its latest generation iBias, high-efficiency power amps. That's a really big deal because while Krells have always sounded great, they sucked a lot of AC power out of the wall socket. They ran hot, so hot you couldn't rest your hand on the chassis, because most of the AC juice was converted to heat, not to making the power that drives your speakers. The heat was an unfortunate byproduct of Krell's Class A circuitry, but the company is going green with its new iBias designs that maintain the sound quality Krell is known for. Krell's iBias, a patent-pending new technology, still uses Class A circuitry, but consumes far less energy than a traditional Class A amplifier.

Krell claims the iBias circuit works by continuously measuring the current flowing through the amplifier's output transistors, and instantly adjusts the power (or bias) going to the transistors, so little AC power is wasted.

Bill McKiegan, president of Krell Industries, made the following analogy, "The iBias amplifier is like a high-efficiency 12-cylinder automotive engine in which some of the cylinders shut down when you don't need all that power." He continued, "Just as that engine can run efficiently yet deliver 600 horsepower in an instant, the iBias amplifier can run efficiently yet in a matter of microseconds gives hundreds of watts of full Class A bias for musical peaks."

Prices for iBias amplifier start at $7,500 for the 2x175-watt Duo 175 amp, and run up to $11,500 for the 3x300-watt Trio 300 amp. There are also five- and seven-channel home theater amps; in all, there are seven models in the iBias line up. Krell will start shipping iBias amps in late January.