60W SET | STEREO POWER AMPLIFIER

The Diana Forte SET power amplifier is our bridge between the Concero 25 and the Concero 65 monoblocks. Massive performance from quite possibly the most powerful SET stereo amplifier in production today.

“The Diana Forte SET power amplifier is our bridge between the Concero 25 and the Concero 65 monoblocks. It is our ‘compact’ stereo version of the venerable Concero 65 Reference monoblocks. Massive performance from quite possibly the most powerful SET stereo amplifier in production today.

Introduced in 2015, and based on our pioneering legacy Diana Integrated, the Diana Forte is simply huge in all aspects. Weighing some 120 kilos and 600cm wide x 590cm deep, it’s quartet of 845 power tubes that tower above the top plate and a pair of E280F driver tubes.”

DESIGNER

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The Diana Forte’s circuits are based on the ground breaking legacy Diana Integrated amplifier model.

Output Stage

The Diana Forte’s circuits are based on the ground breaking legacy Diana Integrated amplifier model, both in it’s output and driver stages. The Output stage is scaled up to deliver over twice the power achieving a true 60W (70W peak) of SET magic per channel. The parallel SET output stage is built around the 845 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 output stage uses the best in class Elrog 845 tube, current manufacture in Germany. This 845 DHT tube is loaded with a special quality Double C-Core bifilar wound inter-stage transformer. The Diana Forte’s amplifier is connected to an accompanying Aries Cerat pre-amplifier via our proprietary AC link. The redesigned high gain version of the Diana Forte is designed to operate with any high quality preamplifier, but also use in full advantage it’s AC link input, when paired with any AC pre-amplifier.

As with our SOTA Concero 65 range of amplifiers, all stages in the Diana Forte are coupled with our special AC link method of coupling, delivering superior performance in the frequency extremes, fast transient response.

Driver Stage

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

All four filament and two heater PSUs are triple filtered, ensuring this all DHT power amplifier delivers the lowest noise floor of any SET power amplifier.

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Power Supply

The output stage power supply unit is a dual array, with a completely separate set of choke filtered capacitor banks using our unique Super-capacitors. The SuperCaps come from a selection of special purpose film capacitors with ESL and ESR parameters 100 times lower than any other film or electrolytic capacitor. The high energy, high speed capacitor banks deliver a superbly robust power rail for the parallel SET output stage.

 

Biasing

All tubes can be biased and monitored on the fly as well as checked for matching using the built-in meters as a stripped down tube matcher.

Technical Specifications

SPECIFICATIONS

Output Power:

60W SE Class A (70W peak)

Gain:

21db

Noise floor:

<100db (Ref) un-weighted

Tube list:

2 x E280F Siemens, 4 x 845 Elrog

Distortion:

-40db H2 @50W

Full power bandwidth:

-5db @ 8Hz -3db @ 70khz

Energy storage:

2000j

Power supply:

1,800VA power transformer

Inputs:

RCA, AC link proprietary input

Output impedance:

(user selectable) 2, 1.1, 0.5 ohm

Tube Bias:

Adjustable bias on the fly

User readouts:

Output and driver online monitors

Capacitors:

No capacitors in the signal path.
SuperCapacitors used for output and driver power supply
(1mohm ESR capacitors)

Power Consumption:

500W

Dimensions:

600mm W x 590mm D x 360mm H

Weight:

110kg