General informations

Integrated amplifier

DUETTO integrated amplifier has been developed in order to provide a very good quality device to all the customers that prefer a small-power hi-fi system, for a lot of reasons: inside it, there are resumed twenty years of CABRE Hi-Fi experiences in multi-case amplification systems (like components with separated preamplifiers and power amps), and the result of this is a no-compromises realization and an excellent musical quality.

A lot of presently produced integrated amplifiers have only one power supply section that provide energy for both small signal and power parts of the amplification chain: this choice forces the project decision to be taken in order to satisfie the opposite necessity of a low noise alimentation for the small signal preamplification section and a high current supply for power section, and the result is often inadeguate for both of them.

CABRE DUETTO intends to give a sharp answer to such questions, by using a project scheme than include a preamplifier and a semi dual-mono power amplifier, that are separated each other from the supply section (obtained by using two toroidal transformer) up to the outputs.

Looking at these aspects, it is not ambitius to say that DUETTO is able to furnish to its owner a product that resume inside it a good estetical "appeal" and the musical perfection: the reduction of external encumbrance and a perceptible sound quality are results of a lot of technical choices done during the project development.

The power amp section, with its complementary circuit (from input to output) and the low global and local feedback factor, include all the best characters of CABRE tradition. The semiconductor polarization is calibrated to obtain the maximum performance from the transistor used, especially in speed response and its linearity and in output current supply, with particular attention to the reduction of even-order armonics in case of power supply "clipping".

The preamplification section has a simple and linear electric layout, that results in a good input sensitivity, a very low total distortion and an excellent dinamic behaviour: this performance is obtained by using very-low noise semiconductors that are able to furnish a very linear and extended frequency response. Particular attention has been included in the choice of the input selector, that is a double-section gold plated rotary switch, and the volume and balance potentiometers, that are very good quality components.

All the aspects emphasized above are the result of about two years of sperimentation, during which CABRE has developed a product layout that include all the electric components in one only printed circuit board (with 70 microns thick tracks).