Aries Cerat · Power Amplifiers
Diana Forte
A sixty-watt per channel parallel single-ended triode powerhouse of unmatched authority.
Building upon the legacy of the pioneering Diana Integrated, the Diana Forte is a massive stereo power amplifier engineered for those who demand the transparency of a single-ended triode circuit without dynamic constraints. It scales the original design to deliver a robust 60 watts per channel, creating one of the most powerful and capable stereo SET amplifiers currently in production.
At its core, the Diana Forte utilises a parallel SET output stage constructed around the legendary 845 directly heated triode. This is driven by an equally sophisticated stage featuring E280F tubes and double C-core bifilar-wound inter-stage transformers, ensuring the output tubes are controlled with absolute linearity. Every stage is coupled via the company's proprietary AC link method, a design choice that preserves phase integrity and transient speed across the entire frequency spectrum.
The power supply is a masterclass in engineering, featuring a 1,800VA transformer and a dual-array of choke-filtered energy banks. By utilising proprietary film SuperCapacitors with extremely low ESR parameters, the amplifier maintains a rock-solid power rail even during the most demanding musical crescendos. The result is a sound that is both startlingly fast and harmonically complete, presenting a three-dimensional holographic stage with physical weight and effortless authority.
Key Features
01
Parallel 845 DHT Output Stage
Utilises two 845 directly heated triodes per channel to achieve 60 watts of pure Class A output power.
02
SuperCapacitor Power Supply
Features a dual-array of film SuperCapacitors with ESR parameters 100 times lower than standard electrolytic capacitors for instantaneous energy delivery.
03
AC Link Coupling
Proprietary coupling technology that eliminates signal capacitors from the path, ensuring superior frequency extremes and transient response.
04
On-the-fly Bias Monitoring
Built-in digital displays allow for real-time bias adjustment and matching of all tubes without external equipment.
05
Triple-Filtered Filament Supplies
All DHT filaments are powered by triple-filtered DC supplies to ensure an exceptionally low noise floor below -100dB.
Chapter 01
Engineering Philosophy
The Diana Forte was born from a desire to scale the success of the Diana Integrated amplifier into a dedicated power amplifier capable of driving virtually any loudspeaker. By focusing on the absolute purity of a single-ended triode topology and removing every possible bottleneck—most notably by replacing standard capacitors with proprietary SuperCapacitors—the designers have created an amplifier that behaves with the effortlessness of a massive solid-state design while maintaining the harmonic delicacy of a refined triode circuit.
Chapter 02
Build & Magnetics
The build quality is defined by its sheer physical scale and the quality of its bespoke magnetics. The oversized output transformer is hand-wound using advanced techniques to ensure bandwidth stability even at full power. Every power rail is independent and choke-filtered to prevent inter-stage crosstalk, and the entire chassis is constructed to provide massive structural rigidity, reflecting the 110kg weight of the components within.
Chapter 03
Sonic Signature
The Diana Forte is often described as a sonic hologram. It presents music with a combination of textural density and explosive dynamics that few amplifiers can match. It does not 'soften' the music; instead, it reveals the full scale of a performance, with bass that has genuine wallop and a midrange that feels palpably alive. It is a rare instrument that remains equally composed during quiet, delicate passages and sudden, thunderous orchestral peaks.
Specifications
Output Power60W SE Class A (70W peak)
Gain21 db
Noise Floor<100db (Ref) un-weighted
Tube List2 x E280F Siemens, 4 x 845 Elrog
Distortion-40db H2 @50W
Full Power Bandwidth-5db @ 8Hz -3db @ 70khz
Energy Storage2000j
Power Supply1,800VA power transformer
InputsRCA, AC link proprietary input
Output Impedance(user selectable) 2, 1.1, 0.5 ohm
Tube BiasAdjustable bias on the fly
User ReadoutsOutput and driver online monitors
CapacitorsNo capacitors in the signal path. SuperCapacitors used for output and driver power supply (1mohm ESR capacitors)
Power Consumption500W
Dimensions600mm W x 590mm D x 360mm H
Weight110Kg