Genesis I 60 amplifier

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)