BLOG - CLASS D - TOP OF THE CLASS IN AFFORDABLE, HIGH OUTPUT HIFI AMPLIFICATION
Updated: Aug 7
For 27 years, Class D amplification has quietly evolved in the background — likely far longer than many enthusiasts realise.
When Danish company ICEpower first emerged under the umbrella of Bang & Olufsen, it seems there was a perception that Class D was destined primarily for stylish lifestyle products rather than serious high-end audio. And, to be fair, in 1999 that perception may not have been entirely unfounded. Now independent from Bang and Olufsen since 2016, it seems the push into high end by ICEPower is the future of amplification.
Since then, however, manufacturers around the world have relentlessly pushed the boundaries of what these compact, cool-running amplifiers can achieve. Delivering output levels well beyond their size, Class D amplification has unquestionably matured.
In fact, during a recent podcast discussion featuring Srajan Ebaen of 6moons and Darko Podcast, Edgar Kramer from SoundStage! Australia, and myself, Srajan openly declared himself a strong supporter of Class D. His view was clear: not only is Class D likely the future of amplification, but right now it arguably represents the best value-for-money proposition in high-end audio.
With the new design from ICEpower now pushing further into the serious high-end space, that argument only becomes stronger.
The company’s latest module, the SC400A2, offers impressive power output, but raw power it not what it's really about. ICEpower’s focus is more related to complex feedback circuit design and "Super Conductor Topology" providing refinement, purity, and transparency above anything previously delivered.
The specifications are certainly worth noting - 400 watts RMS into 4 ohms x 2 from an exceptionally compact module. We can only assume this is a value for money product with no pricing available at this stage.
ICEpower explains:
"While recent industry trends have highlighted ‘fully digital’ Class D concepts, ICEpower's engineering approach is rooted in the reality that loudspeakers fundamentally require analog voltage and current. Recognizing that the switching cycle of any Class D amplifier is inherently analog, the Super Conductor topology therefore corrects signal errors directly in the analog domain. By maintaining a completely analog signal chain, modulator, and feedback path utilizing the highest-performance operational amplifiers available, the platform delivers a newfound level of signal purity."
ICEpower CTO Patrik Bostrøm elaborates further:
“It is an analog Class D amplifier with a Globally Controlled Oscillation Modulator (GCOM) as a core, and two nested second-order negative feedback loops around it.” “Nested negative feedback loops aren't new in themselves, but having a fourth-order slope which also joins the slope of the output filter presents challenges. It has required a lot of work.”
And perhaps most revealingly:
“The unyielding nature of this design required carefully curated components and a surgical approach to layout precision. We have gone all in using the best capacitors, MOSFETs, resistors and OPAMPs. Everything has been scrutinized, measured, and tested. The SC400A2 truly has a state-of-the-art performance, and that is why we call it "The Super Conductor.”
To me this sounds incredibly complex. The thing is that they have already done the hard work, leaving the manufacturer to concentrate on other aspects of the design. That means more time and resources can be devoted to other critical areas of amplifier design such as input stages, volume control, switching implementation, chassis layout, isolation, industrial design, and overall voicing. It can also shorten development cycles and potentially reduce costs by dramatically lowering the R&D burden associated with designing a high-performance output stage from scratch.
That, in turn, could make genuinely high-end performance more accessible.
We’ll be getting a closer look at this new technology at High End Vienna 2026, where ICEpower will be demonstrating both the SC400A2 module and its matching 750S switch-mode power supply.
PS The "IceBreaker" Class D Amp design, build, blind test project is underway with Episode 059 including an interview with the ICEPower designer.
