The Obelisk PS is a versatile stereo power amplifier, rated at 50 watts per channel into 8 Ohms, yet performing like a much higher rated amplifier due to its unique circuit topology and outstanding power supply section. It is entirely suitable for bi-amping, tri-amping or multi-room use. It is a perfect match for the Obelisk PRE.
But above all, the PS is every bit an Obelisk. It exemplifies Heed's long-standing tradition of eschewing DC-coupling for a less “processed” sound with more natural decay of tones and uncanny realism has reached new heights with the evolution of the Obelisk PS. With the capacitor-coupled power amp stage of the Obelisk Si integrated (even more effective when quasi-pre/power configured with the addition of the X-2 PSU), Heed have created a distinctively different sound signature much closer to the best of valve amplification than to conventional solid state presentation, as noted by many prominent hi-fi journalists:
"It is much closer to the ‘live’ magic of a reference-quality 300B than it really has any right to.” (Thierry Soveaux, Diapason).
"It really does make that solid-state valve-sound a little closer to reality.” (Jason Kennedy, Hi-Fi Choice).
"With its liveliness and ease it’s geared toward the intrinsic virtues of good valve amplifiers.” (Markus Sauer, Hi-Fi Statement).
When you own a Heed amplifier you meet technology that you most probably have never seen in action before. Like the almost forgotten (and then reincarnated) valve technology, the output capacitor transistor amplifiers can normally only be found in the deepest recesses of engineers drawers. The technical difficulties of RC-Coupling means almost 100% of todays manufacturers opt for the easier direct-coupled solutions instead. With great effort and countless development hours there is a way to employ an up to date and sonically better sounding RC-Coupled amplifier. Heed have chosen this way.
Like the belt of a great turntable or the output transformer of a valve amplifier, the output capacitor makes for a great decoupling between the amp and the speaker. But the main advantage is the fact that a capacitor is an energy storage device. By design, this capacitor connects directly onto the speaker, with no in-between elements. Power delivery becomes rapid and precise. To charge this power element, Heed use a push-pull complementary Darlington transistor drive stage.
This power transforming system needs to be perfectly balanced. The heart of Heed's Transcap technology lies in the precise adjustment of all the charge transmitting and current delivery channels. This propels all the common amplifier components; mains transformer, power supply, voltage and power amplifier stages, into something radically different. You may see now, this is no ordinary amp and it cannot be measured by common standards. Heed by using these methods, enable the amplifier sound to become thick, warm, yet clear and life-like, as it properly translates the electronic signal into the acoustic world.
The PS proves that it is possible to push the envelope of the Obelisk topology. In doing so, Heed have followed a simple path: They kept the proven dual-mono power amp circuit of the Si, improved its PCB layout, optimized all signal paths, opted for higher grade components, and upgraded the entire power supply. The result speaks for itself. The Obelisk PS, along with the PRE/Dactil and DT digital transport won Diapason D’Or 2009 and 6 moons’ Best of The Year — Writers Favorite 2010.