Trilogy 994 Mono Power Amplifier

Priced per pair. The 994 is a mono amplifier and is sold as a matched pair of monoblocks.

The 994 is a zero negative feedback hybrid mono power amplifier. Trilogy describes it as embodying much of what the 995R does in a smaller and equally distinct sculpted form. It offers 140 watts into 8 ohms in Class AB and significantly more into lower impedances — 200 watts into 4 ohms. A 6H6П valve in a grounded grid configuration drives Trilogy's compound output stage, and a massive choke input power supply sits behind it.

Like the 995R, the 994 runs in three modes. In Class AB it still uses significant quiescent current, and the high voltage supply enables the greatest output power the mode allows. In Class A the operating voltage is reduced and quiescent current raised so the output stage's current requirement is more or less constant with respect to signal; output falls to 20 watts rated into 8 ohms, the harmonic structure becomes richer and more fluid, and the amplifier runs significantly warmer. ecoA holds pure Class A the whole time music is being amplified, then drops quiescent current dramatically if no signal is detected for a minute, returning to Class A instantaneously.

The 994 is a mono amplifier and is used in pairs. Frequency response runs 2 Hz to 100 kHz within half a decibel, into a recommended load of 2 to 16 ohms. hi-fi+ reviewed the 994 monos with the 914 preamplifier in May 2025.

• Rated power (Class AB): 140 watts into 8 ohms; 200 watts into 4 ohms
• Rated Class A power: 20 watts into 8 ohms; actual usable 30 watts into 8 ohms, 55 watts into 4 ohms
• Modes: Class AB, Class A, ecoA
• Topology: hybrid; 6H6П grounded grid driving compound output stage; zero negative feedback; massive choke input power supply
• Recommended load impedance: 2–16 ohms
• Input: 1 RCA phono socket; 200 kohms; gain 31 dB; 1.1 V RMS for rated output
• Frequency response: 2 Hz – 100 kHz +/- 0.5 dB
• Distortion: less than 1% A weighted at rated output into 8 ohms
• Phase: phase correct (non inverting)
• Power consumption: below 1 W standby / 600 W maximum
• Dimensions / weight: 190 x 365 x 312 mm (190 x 400 x 312 mm including connectors) / 25 kg per unit