Power amplifiers stereo — Gryphon Audio ESSENCE

The Essence is a stereo power amplifier built by the Danish maker Gryphon Audio, working in pure Class A and also sold in a monoblock version with higher ratings. Flemming E. Rasmussen styled the exterior and Tom Møller engineered the electronics, with design and manufacture in Denmark. Gryphon describes the power ratings as conservative.

Key specs that matter

Rated output is 2 x 50 W into 8 ohm, 2 x 100 W into 4 ohm and 2 x 200 W into 2 ohm at 115 V or 230 V. THD+N is below 1 percent at 50 W into 8 ohm, and IMD (DFD) stays under 0.05 percent at 25 W into 8 ohm. Output impedance is 0.015 ohm. Gain is +31 dB, input level is 0.564 Vrms and the balanced input impedance is 20 kohm. Noise measures below -78 dBV unweighted across 20 Hz to 20 kHz and below -81 dBV A-weighted. Consumption peaks at 1,350 W, idles at 350 W on the high bias setting and falls under 0.5 W in standby. The case is 47 x 24 x 46 cm and weighs 45 kg net.

Engineering and use context

Gryphon uses a pure dual mono layout, avoids any global negative feedback and applies DC servo coupling. A single custom 1,350 VA toroidal transformer feeds a 440,000 uF capacitor bank, and the output stage carries 20 Sanken bipolar transistors, 10 for each channel. The input and voltage amplifier stage are fully balanced. The output, driver and control stages each get their own supply, and digital and analog sections are powered apart as well. Four-layer circuit boards carry copper up to 70 um, and signal and power wiring inside is Gryphon silver. The damping factor is frequency independent, and a soft start avoids tripping household fuses or breakers. An RGB LED bar shows whether high or low bias is active, and a microprocessor controls the non-invasive protection system. Mains power enters through one C19 inlet.

Pairing

Signals come in through gold-plated Neutrik XLR sockets, and the speaker terminals are Gryphon's own gold-plated binding posts. Bias can follow a Gryphon preamplifier automatically through the Green Bias control link or be set by hand to Low, Mid or High, and a 12 V link turns the amplifier on and off remotely. The monoblock version is rated at 55 W into 8 ohm with an output impedance of 0.0075 ohm, and each monoblock doubles the capacitor bank to 880,000 uF with 20 output transistors. The stereo unit ships in a 59 x 57 x 38 cm carton weighing 57 kg.

Alternatives

A bigger stereo choice from Gryphon is the Hyperion, a dual mono Class A design with far more output.