KRELL KSA-100

Commentary

Kroell's first announcement of a stereo power amplifier.

A pure complimentary service circuit with pure A-class operation is used for the circuit, and consideration is given not only to the simple amount of harmonic distortion but also to the appearance of the distortion mode influenced by the sense of hearing.
In addition, NFB is limited to 15 dB with an emphasis on dynamic characteristics.

In order to cope with heat generation, which is a problem in pure A-class operation, the power block is composed of a heat sink and an extremely quiet cooling fan. The generation of thermal distortion is suppressed by strictly controlling the temperature of the power block to 75-80 degrees.

The power supply section is equipped with a 160,000 μ F capacitor and two 1.1 kW-class toroidal transformers. This is a large power supply equivalent to a 400W-class amplifier for general B-class operation. By ensuring sufficient allowance, load fluctuations during actual operation of the speakers can be coped with. As a result, even if the impedance drops to 1 Ω, the calculated output of 800W + 800W can be sent out stably.

The inside is a twin monaural configuration with complete L/R independence. Only the power switch and AC cord are common, and the left and right and right sides are completely independent except for that.

Model Rating

Type	Stereo power amplifier
Rated output	100W + 100W (8 Ω, 20 Hz to 20 kHz, when both channels are driven simultaneously) 200W + 200W (4 Ω) 400W + 400W (2 Ω)
Input Sensitivity / Impedance	1V/22k Ω
Total harmonic distortion factor	0.05% or Less (20 Hz to 20 kHz, 1W to Rated Output)
Frequency characteristic	0.5 Hz ~ 100 kHz -3dB 20 Hz ~ 20 kHz -0.5 dB (1W ~ Rated Output)
Signal-to-noise ratio (IHF-A)	110dB
Rated load impedance	2 Ω or more
Damping factor	120(1kHz)
Slew rate	80 v / μ sec
Pwer	100 VAC, 50Hz/60Hz
Power consumption	610W (maximum idling)
External dimensions	Width 483x Height 226x Depth 612 mm
Weight	Approximately 35 kg