FEATURES
PRODUCT FEATURES
The SLI-80HS is one of the most exotic integrated stereo audio amplifiers available. Within its power
range, the SLI-80HS displays the operating characteristics of a true "high-end" amplifier. Careful design,
parts selection and proper circuit topologies contribute to incredible reliability and enjoyment.
The SLI-80HS integrated stereo amplifier operates in a Class AB1 mode utilizing a negative fixed bias
supply. The KT88 output tubes are configured in push-pull and yield 40 watts/channel in triode mode
and 80 watts/channel in ultra-linear mode of output power.
The output transformers in the SLI-80HS are the most important component in the amplifier and have
been specifically designed by Cary Audio for use in the SLI-80HS. Negative feedback is derived from
the 8 ohm tap on the output transformer secondary. This feedback circuitry is used to reduce the noise
floor and improve the speaker damping characteristics. Only 4 dB of feedback is utilized. The phase
inverter is a self-balancing split load configuration utilizing the 6SN7 octal base dual triode. The
preamplifier circuit is a Series Regulated Push-Pull (SRPP) Class A triode voltage amplification stage
direct coupled to the phase inverter. The power supply in the SLI-80HS features a 200% duty cycle EI
laminate power transformer.
The input signal from the volume control is direct coupled (DC) to the first grid of the 6922. There are
no coupling capacitors in line with the input signal on the SLI-80HS. The sub-woofer output is derived
from the wiper of the volume control.
A great deal of attention during design of the SLI-80HS was concentrated on the "overload recovery"
ability of the amplifier. The ability of an amplifier to instantly recover from clipping is much more
important than is commonly believed. In the power war of amplifier manufacturers, the mentality is
focused on high and then even higher power output to solve the clipping problem. When in reality, the
most critical aspect is how fast a recovery an amplifier can achieve after overload. Most of the music
being listened to in an average listening room is only requiring about 3 watts of power. It is on the
transients of loud low frequency program material that tremendous signal voltages will appear at the
input of the amplifier. It is in this situation that the overload recovery ability of an amplifier is of critical
concern. The SLI-80HS will overload symmetrically at any frequency in the audio band-pass. The SLI-
80HS will also yield faithful reproduction of extremely low frequencies at full output levels. Power
transformer, power supply regulation, and output transformer design and careful shaping of the overall
frequency response curve all play a very important part in the ability of the SLI-80HS to recover quickly
when overloaded. The high voltage rail will fluctuate no more than a volt between soft and loud
passages.
Another feature of the SLI-80HS, aside from how compact and gorgeous it looks, is the delightful,
sensual beauty of the music it recreates. The first thing that will strike you about the SLI-80HS
integrated amplifier is the incredible transparency and resolution of detail in the music. The SLI-80HS's
sensual nature is best revealed in the sense of life it displays in female vocalists. The SLI-80HS
integrated amplifier presents music with such presence and directness, you'll be drawn into the music
hour after musically satisfying hour. This is the result of circuit techniques, which eliminate any
discernible crossover notch at low levels, and also contributes to the freedom from listening fatigue.
The SLI-80HS will draw you in even further as you realize how lucid and utterly uncolored neutrality
reveals delicate nuances in the sound stage.
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