Pre/Power Amplifiers

While the H30A is a stereo power amp, and will surely be purchased by audiophiles for use as such, Hegel still limits its specification to the H30A's bridged monoblock performance. These are the numbers you'll see copy 'n pasted into every other review of this amplifier. That's not the HFN way so I thought we should don the welding gloves and check for ourselves...

Bridging the H30A's two channels doubles the available rail voltage and realises 1.24kW/8ohm and 2.115kW/4ohm, figures that are comfortably in excess of Hegel's rating. There's more under dynamic, music-like, conditions [see inset Graph] with 1.31kW, 2.59kW and a thumping 4.99kW (50A) available into 8, 4 and 2ohm, respectively (re. 10msec at <1% THD). Bridging also means the amp 'sees' half the load connected in stereo guise, so Hegel has current-limited the H30A's output to just 655W/1ohm here, protecting the amp against accidental shorts. In practice, the maximum current available is no different in either stereo or bridged mono modes just as the H30A's overall gain is fixed at +32.1dB and the A-wtd S/N remains between 87-88dB (re. 0dBW). The low distortion is also retained in bridged mode, settling between 0.0016-0.002% over the first 200W/8ohm, increasing slightly thereafter up to a mere 0.0024% at the rated 1kW/8ohm (all re. 1kHz). In either mode, the H30A is a super-clean beast! PM