Aries Cerat have announced the completion of the Diana Series of amplification with the introduction of two new models, the Diana Forte amplifier and the Diana Mezzo, Class A pre-amplifier.

 Diana Forte Stereo Power Amplifier

The Diana Forte’s circuits are based on the Diana Integrated amplifier output and driver stages. The Output stage is scaled up to deliver over twice the power, achieving 60W (70W peak) per channel. The parallel SET output stage is built around the 813 DHT big bottle tube.  This in turn drives an oversized core OPT constructed using special winding techniques to deliver wide bandwidth at full power. 

The amplifier driver stage is the 814 DHT tube, loaded with a double-C core bifilar wound inter-stage transformer. The Diana Forte’s amplifier is connected to its accompanying Diana Mezzo pre-amplifier via Aries Cerat proprietary AC link. As with the Diana Integrated and the Concero amplifiers, all stages are coupled with the company’s AC link method of coupling.

The output stage PSU is a dual, completely separate set of choke-filtered capacitor banks using yhe company’s own Super-capacitors.  The SuperCaps come from a selection of special purpose film capacitors with ESL and ESR parameters 100 times lower than any film or electrolytic capacitor.

The driver stage also uses choke filtered capacitor banks, with their own separate power transformer to avoid PSU cross-talk.

All tubes can be biased and monitored on the fly and can be matched using the Diana Forte as a stripped-down tube tester.

Specifications

Max Power: 60W SE Class A (70W peak)

Max Power bandwidth: 15Hz- 110Khz

Noise floor: 100db

Combined gain: X 20 (26db)

Dimensions: 570mmW X 590mmD X 350mmH

Weight: 110Kg unpacked

Tubes: 2X814, 4 X 813

Diana Mezzo Pre-Amplifier

The Diana Mezzo is an improved version of the Diana Integrated’s pre amplifier stage. At its heart, the Diana Mezzo is a Single Ended Triode amplifier boasting an 814 Direct Heated tungsten DHT.

The output transformer is a double-C amorphous core, bifilar wound OPT.

Signal attenuation is performed by a relay-switched array of resistors, in a shunt/ladder hybrid mode.

A pair of Xenon gas rectifiers are used as rectifiers of the High Voltage PSU.

These rectifiers were developed as drop in replacements for some well known mercury rectifiers when mercury was labeled unsafe. So while they present the technical characteristics of a mercury rectifier, they are safe to operate. The high speed capacitor banks are double choke filtered.

Filament PSUs are quadruple filtered using a cascade of choke/resistor-cap pi filters providing very low noise floor for the sensitive filaments of the DHTs.

Specifications

Gain: X7 (16db)

Attenuation level: 61 X 1db steps

Maximum signal input overload: 25V

Signal bandwidth @ 20Vrms: 10Hz-120Khz (-3db)

Dimensions: 500mmW X 350mmD X 340mmH

Weight:  55Kg

Tubes: 2 X 814, 2X 3b28