Back in the 1980s and 1990s an electronics engineer called Richard Hay designed a number of amplifiers under the Nytech and Ion Systems brand names that gained an almost cult following.

Unfortunately, despite Hay's enthusiasm, both Nytech and Ion failed, and with them, the popular Obelisk amp design disappeared from the market. Gone, but not forgotten: the Ion Obelisk still has its followers, especially within the Hungarian hi-fi fraternity at Heed Audio, makers of various electronics components including pre/mono amplifiers, headphone and phono amps and even turntable power supplies.

Heed's Zsolt Huszti decided to rebuild the Obelisk, basing its power amplifier on Richard Hay's design, albeit with heavy revision and the addition of his own preamp section.

The Obelisk Si (Super integrated) is the first example of what Heed intends to be a small range of amplifiers that will include an entry-level model and a power supply (X-2) that forms a dual-mono supply for the power amp section of the amp.

To this end, the Obelisk Si comes with a blank connector to bridge the power supply input, the presumption being that the external supply will be added at a later date. This is similar to the upgrade routes offered by Naim and Cyrus.

The Obelisk features one pre-output and five line inputs, one of which can have an internal card added to turn it into either a phono stage, or a digital to analogue converter (DAC). At the time of writing, neither were available.

Power is specified as 40 watts a side. Heed is at pains to point out that the Obelisk is not DC coupled, something which Zsolt has very little time for, although this hardly picks him out from the crowd. He also describes the power amp as a "valve amp built with transistors", the inference being that it clips in the smooth style of a valve amp.

The Obelisk does indeed display some valve-like traits, most notably a good grasp of dynamics that injects music with a liveliness and energy that is easy to enjoy. It doesn't, however, have a smoothed-off top end, but instead, seems to stretch further than one might expect of a compact 40 watt design.