Introduction
The Genesis
Integrated 60-Watt Stereo Valve Amplifier uses proprietary technology, high
quality components, and state-of-the-art vacuum tube topology to deliver sonic
performance rivaling other amplifiers costing much more. The design objectives
of this product are to:
1. Deliver musically
accurate amplification,
2. Provide a vacuum
tube amplifier that would approach the reliability and ease of use of solid
state amplifiers,
3. Provide an
affordable vacuum tube amplifier that would be able to drive the Genesis family
of loudspeakers.
A valve amplifier
matched with an appropriate loudspeaker can produce a sound that we can only
call magic. The hard, brittle, and edgy presentation of many transistor
amplifiers is contrasted with the rich, lush and silky sound of the tube
amplifier. Often, tube amplifiers offer much better imaging and sound stage
presentation compared to an equivalently priced solid-state amplifier. It is
more musical, and the performance seems almost alive. A properly designed and
built tube amplifier, such as the Genesis I60, is capable of reproducing
midrange and treble with crystal clear definition – the
sound can only be
described as smooth and silky, and musically accurate with the right timbre and
harmonics.
As for the bass, the
I60 is designed to maintain tight control over the bass, and deliver the
powerful punch and dynamics at the low end with the solidity and weight of
transistor amplifiers.
Design and
Construction
The I60 is an
integrated amplifier with four high-quality selectable inputs and a discrete
resistor ladder potentiometer as a volume control. It uses a single 12AX7 per
channel as the main voltage gain stage, with 6SN7’s as the driver stage. No
ordinary 6SN7’s for the I60 – military spec 6N8P are selected for their
reliability and durability, and then hand-picked for linearity and low noise.
Two sets of matched-pair KT88 power output valves are used to deliver a very
conservative 60 watts RMS per channel.
While the I60 is
developed as a value-priced product, quality has not been scaled down.
Extensive listening tests were done throughout the design process, and
expensive components were used where they were appropriate. Custom-made
military-spec paper-in-oil capacitors with aluminum cans are selectively used;
a hand-built discrete resistor stepped attenuator is employed as a volume
control; low-noise gold plated militaryspec ceramic tube sockets are used
throughout.
Very little feedback
is used – just enough to make the amplifier unconditionally stable. Not the
excessive amount that is sometimes employed to make amplifiers measure better
at the expense of musicality.
During construction,
all components are handselected and precisely matched. The output transformers
and power transformer are laboriously hand wound to precise specifications
tailored to the circuit and tubes used. Point-to-point wiring using solid-core silver
wire is used in the entire signal path. This reduces the resistance,
capacitance and nductance normally
associated with ordinary printed circuit boards.
The only PCBs you
see in the “guts” above are the boards associated with biasing of the power
tubes, and the soft-start lectronics. The output transformers are custom
designed and hand-wound with a core of grain-oriented silicon steel
specifically for the output tubes used. Two output taps are provided on the
secondary – 4ohm and 8ohm – with the 4
Ohm tap specifically
tuned using Genesis loudspeakers. Each amplifier is extensively inspected and
tested at every stage of manufacturing. It is also allowed to burn-in before
the valves are biased and calibrated, and then run-in for 100 hours before finally
being electronically tested prior to packing for shipment. Hence, it should
come to you ready to use straight out of the box.
The Genesis
Integrated 60-Watt Valve (or vacuum tube) Amplifier is a limited-edition
product that was created as proof of concept that a welldesigned,
well-executed, value-priced amplifier will be able to drive any Genesis
loudspeaker with ease and authority.
The transparency,
detail retrieval, dynamics, and wide frequency extension of Genesis
loudspeakers place great demands on the quality of amplification. Because of
our emphasis on absolute fidelity™ above all else, the speakers do represent a
difficult, but not impossible load for an amplifier to drive. The I60 was
created as a partner to a pair of Genesis loudspeakers, and as a result, it has
the quality of amplifiers costing much more.
The I60, together
with a pair of Genesis loudspeakers, will give your entire music collection a
whole new life. In a well set-up system, it is capable of transporting the
musical performance into your room. The hiss and hum normally associated with
vacuum tubes are completely absent, while retaining the richness and rightness
of the best of this genre of amplifiers.
While developing a
value-priced product, quality has not been scaled down. Hand-selected,
precisely matched components are used throughout: custom-made military-spec
paper-in-oil capacitors with aluminum cans are
selectively used;
tantalum-film resistors are used on a hand-built discrete resistor
potentiometer as a volume control. The output transformers and power
transformer are laboriously hand wound to precise specifications
tailored to the
circuit and tubes used. Point-to-point wiring using solid-core silver wire is
used in the entire signal path. This reduces the resistance, capacitance and
inductance normally associated with ordinary printed circuit boards. Each and
every unit is first burned-in on the test bench, and then run in for over 100
hours before final test and packaging.
Very little feedback
is used – just enough to make the amplifier unconditionally stable. Not the
excessive amount usually employed to make amplifiers measure better at the
expense of musicality. The result of all this obsessive attention to detail is
a fabulously musical amplifier capable of driving almost any loudspeaker in the
world.
Specifications
Vacuum Tubes: 4 x KT88; 2 x 12AX7: 4 x 6N8P (or 6SN7
equivalent)
Rated Power
Output: 60 W + 60 W RMS
Total Harmonic
Distortion : less than 2,0% at full
rated power
Frequency
Response: 20 Hz - 30,000 Hz, (<1%
T.H.D.)
Input Impedance: 250 k Ω
Output Impedance: 4 Ω or 8 Ω
Preamp Input
Sensitivity: 380 mV
Signal to Noise
Ratio: >90 dB
Dimensions (H x W x
D): 185 x 480 x 380 mm (7 ¼” x 17” x
15”)
Weight: 27 kg
(60 lbs)