Krell Ships S-550i Integrated Amplifier
February 19, 2013
Krell Industries, LLC revealed that worldwide shipments of S-550i Integrated Amplifiers will begin this week.
Delivering 275 watts of output, the S-550i Integrated Amplifier is a robust power source for any speaker, the company says. The S-550i Integrated Amplifier is outfitted with balanced and single-ended inputs, iPod dock, and Theater Throughput mode. Developed by Krell, Theater Throughput simplifies integration into home theater systems. For custom integration applications, 12 Volt triggers, RS-232 connectivity and rack mount ears are included. Operational parameters can be customized via the menu system that is accessible from the front panel or the included brushed Aluminum remote control.
The preamplifier section features circuit concepts from Krell's flagship Phantom preamp. Krell Current Mode provides unequaled bandwidth for playback of today's high-resolution music sources. Direct coupled circuitry eliminates impact-robbing capacitors from the signal path and an elegant, custom-machined level control adjusts volume. Discrete circuitry, in a balanced topology, is afforded its own power supply regulation. All signal gain is realized using surface mount technology featuring proprietary current mirrors with nearly 500 times the open loop linearity of other designs. Negative feedback is not used anywhere in the preamplifier, nor is it necessary. Open-loop distortion is typically less than 0.003 percent. The volume control is realized with a balanced resistor ladder—bandwidth and transient response of the preamp circuitry are virtually unaffected by the volume setting.
The S-550i packs a 1,750 watt transformer and 68,000μF of capacitance into a 5-inch high chassis. This power supply feeds classic Krell circuitry throughout the topology using only discrete circuitry. As with all Krell amplifiers, the S-550i design is an ideal voltage source. That is, the S-550i doubles its power output when a speaker's impedance is halved. For the S-550i, the results are 275 watts into 8 Ohms and 550 watts into 4 ohms both channels driven.
The S-550i Integrated Amplifier retails for $5,000 and is available now in silver and black finishes.