Power amplifiers stereo — Gryphon Audio ANTILEON EVO

The Antileon EVO is a two-channel amplifier from the Danish company Gryphon Audio, which also builds it as a single-channel monoblock. Exterior design is credited to Flemming E. Rasmussen and electronics design to Tom Møller, and Gryphon builds it at home in Denmark. Its predecessors were the Antileon Signature and, before that, the original Antileon.

Key specs that matter

Rated output is 2 x 160 W into 8 ohm, 2 x 320 W into 4 ohm and 2 x 620 W into 2 ohm at 115 V or 230 V mains. THD+N stays below 1 percent at 150 W into 8 ohm, and IMD (DFD) is below 0.06 percent at 50 W into 8 ohm. Output impedance is 0.04 ohm, and the -3 dB bandwidth runs from 0.3 Hz to 350 kHz. Gain is +31 dB with an input level of 0.975 Vrms, and a 20 kohm balanced input impedance. Unweighted noise from 20 Hz to 20 kHz is below -78 dBV, or below -81 dBV A-weighted. Maximum consumption reaches 2,500 W, idle draw with the high bias setting is 500 W and standby is under 0.5 W. The chassis measures 57 x 26 x 60 cm and weighs 90 kg net.

Engineering and use context

The circuit operates in pure Class A with zero global negative feedback in a pure dual mono layout. Each stereo channel has a 335,000 uF capacitor bank, and 40 high current bipolar Toshiba output transistors are fitted in total. Both the input and the voltage amplifier stage are balanced throughout, and signals enter solely through Neutrik XLR connectors with gold plating. Transformer casings are shielded, epoxy damped and suspended for vibration isolation. Other details include Gryphon silver internal signal and power wiring, polypropylene capacitors for local supply decoupling, double-sided circuit boards with copper up to 105 um and a frequency-independent damping factor. A soft start keeps the mains fuses from tripping at turn-on, a separate supply feeds the display and control circuits, and a microprocessor runs the protection system with upgradeable software. Mains arrive through two C13 inlets, and the amplifier ships with spikes and coasters.

Pairing

The Green Bias control link lets a Gryphon preamplifier set the bias automatically, while Low, Mid and High settings can also be chosen by hand. A 12 V link handles remote power on and off, and custom gold-plated Gryphon binding posts take the speaker cables. Gryphon states that its high current design is meant for reactive loudspeaker loads.

Alternatives

Within the Gryphon range, the stereo Hyperion is a comparable two-channel Class A design with 2 x 180 W into 8 ohm.