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The revolutionary Ultrasound amplifiers

 

 

Summary

 

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Foreword

An amplifier is a device that has an electric signal of small entity in input and must transform it in something able to drive a loudspeaker; therefore, it is not sufficient to amplify the voltage of it, but it is also necessary to provide the adequate current. In other words, it must furnish POWER to the loudspeaker. The power can be provided in 3 different way:

 

VOLTAGE driving The output impedance of the amplifier is very lower than that of the loudspeaker. In this way, we keep constant the voltage, while the current varies. It is the simplest system, used by all the solid state amplifiers, but it is the worst from the point of view of the musical result.
POWER driving The output impedance of the amplifier is equal to that of the loudspeaker. The maximum transfer of power is achieved; such a system is used in tube amplifiers (through the output transformers).
CURRENT driving The output impedance of the amplifier is very higher than that of the loudspeaker. In this way, we keep constant the current, while the voltage varies. It is a system never used because his complexity, but it is the best in absolute from the point of view of the musical result.

Due to great transparency and coherence of our speakers, the quality of all components behind is underlined to the maximum. That has pushed us to seek for amplifiers with superior performances than actual ones, with ours usual philosophy: take the way that carries longer, independently from the difficulties and from the costs, with the only limit of the physical laws. Starting from the fundamental point that the music is not made by sinusoids (that is, static signals), but on the contrary by signals quickly varying in time (transitory), we have rejected the voltage driving and choosen the current driving. Since there is no experience on this solution (there are however many convinctions absolutely wrong), we have therefore performed a long research to understand if in this way was possible to design something really better than all amplifiers builded so far.

After many years of research, ULTRASOUND has been able to build some current generators (click on the link for technical info) that directly control the current in the loudspeaker, resulting in a substantial reduction of distortion. These devices represent a real revolution in amplification, offering important advantages as regards the conventional amplifiers:

first, feedback that happens in a voltage-driven loudspeaker is eliminated;
   
non-linearity due to overlapping of forces of different nature in the loudspeaker is also eliminated;
   
frequency response in dynamic regime is extended;
   
better coupling with the loudspeaker is achieved;
   
number of components crossed by the signal is reduced, approaching the ideal of "wire with gain" considered the goal to reach.

 

This search has already lead to the realization of two amplifiers absolutely unique, OTELLO (valves) and PARSEC (hybrid); from the 1996 we are working at the realization of NIHIL, the first (and unique) monocomponent amplifier of the history: that is, if the ideal amplifier is a wire with gain, this is the maximum that can be done.

 

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OTELLO

The first, concrete result of this new technology is represented by the fabulous OTELLO, a dream machine in which the charm of the thermionic tubes is married with the most modern technologies; an OTL with 6 transformers, with adjustable polarisation, without any type of feedback;

an amplifier with zero damping factor that has the fastest and articulated bass that anyone could hear. An amplifier with a cabinet entirely in solid walnut wood, completely hand-wired, in which practically everything has been built ad hoc by three engineers who have worked for almost 5 years on it: an unique piece for a dreaming musical result.

 

OTELLO

Type Integrated
Technology Valves OTL
Output Impedance 200 Kohm
Peak current 8 A
Dimensions 90 x 30 x 70 cm. (L x H x P)
Weight 90 Kg.

 

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PARSEC

The revolution goes on with the PARSEC, which with his megaohm output impedance constitutes an ideal current generator, able to handle 30 amperes on every load. In this amplifier the signal crosses only 3 components (volume control included) between input and output, for a musical result incomparable for transparency, speed and harmonic structure.

Supply transformers separated for each of the components crossed by the signal, stabilised power supply, a 6 position adjustable polarisation, a cabinet entirely in wood to avoid electromagnetic distortions, control of the vibrations produced by the components, minimisation of the mechanical and acoustic feedback, wiring entirely made of copper bars: these characteristics make it a unique piece in the world.

 

PARSEC

Type Integrated, 3 inputs
Technology Hybrid
Output Impedance 1 Mohm
Peak Current 30 A
Dimensions 65 x 30 x 45 cm. (L x H x P)
Weight 70 Kg.

 

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PARADOX & PARADOSSO

PARADOX takes roots in these state-of-the-art amplification systems. PARADOX is an integrated amplifier that, in spite of its small dimensions, preserves many part of the exclusive characteristics of its major brothers: the signal crosses only 3 components, the cabinet is entirely in wood (except the aluminium heat sink for cooling of the components) and the wiring is manual.

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The amplifier is also available in a lower resolution version, denominated PARADOSSO. Both are not current industrial products, but objects of radically new conception able to discover new frontiers in reproduction quality in domestic rooms.
   
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  PARADOSSO PARADOX
Type Integrated Integrated
Technology Hybrid Hybrid
Output Impedance 22 Kohm 27 Kohm
Peak Current 14 A 18 A
Dimensions 50 x18 x 35 cm. (L x H x P) 50 x 18 x 35 cm. (L x H x P)
Weight 12 Kg. 12 Kg.

 

These amplifiers can guarantee higher results than actual amplifiers, incorporating concepts at least 10 years ahead competitors, particularly in the following aspects:

Dynamics better than any other amplifier;
   
Incomparable transient management (no feedback);
   
A better reproduction of the acoustic scene respect to the conventional products;
   
Coherence and transparency unrivalled.

 

The main limit of these amplifiers consists paradoxically (from which the name) in their potentiality, so high to underline all the defects of a hifi system; the technology of current driving has enormous advantages when we are looking for top performances, but it is not 100% substitutable to the poorer voltage driving.

Therefore, ULTRASOUND has developed an amplifier that can replace in all cases the traditional ones, but with superior performances (also if not at the level of the current generators, which are absolutely the best). To obtain this, we have used the power driving, that represents the medium point between voltage driving and current driving: this amplifier has been called FULCRUM.

 

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FULCRUM

It is an integrated with 4 inputs and a tape out, whose circuit is derived directly from the PARADOX. His output allows an adaptation of impedance without using transformers (differently than tube amplifiers), avoiding therefore the problems from them constituted. If your reference is monotriode, you must listen to this to understand what it is possible today!

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  FULCRUM
Type Integrated
Technology Hybrid
Output Impedance 2.5 ohm
Peak Current 15 A
Dimensions 50 x 18 x 35 cm. (L x H x P)
Weight 12 Kg.

 

These amplifiers (due to a different, more advanced technology) allow musical performances much better than the actual ones; the smaller ones (PARADOX, PARADOSSO, FULCRUM), in spite of results impossible for the most expensive high-end amplifiers, have a very lower price.

If the perfect amplifier doesn't exist, ours are those that go the nearest. Come in our showroom or contact an authorised dealer to try them (carrying your reference amplifiers - of any price - for a direct comparison): we will give you an unforgettable demonstration.

 

 

PREAMPS

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Tube Preamplifier. It's a custom tube, not available on the market.

Filaments are battery powered, for total insulation from power network.

Totally wooden frame to avoid electrostatic and electromagnetic distortions.

Built and cabled by hand by professional engineers.

4 o 6 line inputs. Standard finishing: natural wood - silver. Different finishing upon request.

 

 

 

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One custom, air-suspended tube, totally battery powered. Simply the best possible design.

Production and finishing upon request.

 

POWER AMPLIFIERS

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The exclusive technology of power driving at its best.

Sound performances better than monotriode, but with the impact and reliability of solid state. Plus the coherence, the dynamics and the articulation of this exclusive solution: the reduction of distortion respect conventional designs is clearly audible.

Production and finishing upon request.

 

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The revenge of knowledge over stupidity. The only amplifier designed to drive a loudspeaker, not to heat resistors.

Current driving: the best existing technology.

Production and finishing upon request.

 

Current generators: technical info

Ultrasound
Vicolo T. Aspetti, 18
35100 Padova (ITALY)
Tel./Fax: +39 049 8644085

Showroom
Via Bachelet, 20
Busa di Vigonza (PD)
Tel.: 049 8935095

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