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Add some green to your sound. It used to be that when you wanted to sell a product, you added sex. You sold cars when a scarcely clad well-curved lady was strategically draped across the bonnet. You sold loudspeakers when a scarcely clad well-curved lady touched the enclosure while licking her lips. You sold just about anything when a scarcely clad well-curved lady was somehow connected.


Those days are over. Strangely enough the vanishing act of the scarcely clad well-curved ladies is not caused by the global embrace of moral (neo) conservatism or an overall jolt to the right. No, the vanishing of the scarcely clad well-curved ladies comes from an unexpected angle: the environmental movement. Being associated first with long hair, peaceful protests and above all left-wing politics, these ideas and its movement have become fashionable and were adopted—some say hijacked—by the mainstream. This even includes big corporate so dreaded by the hard-core activists. They all embrace the environment now and have turned green (or at least pretend to - money is green after all).


The scarcely clad well-curved ladies have been replaced by a color. Sex has been replaced by a color and that color is hot. Governments are green and offer tax cuts for green products. Buy a car labeled green in Holland and it’s exempt from additional luxury tax and even road tax. The car gets the green label because its carbon dioxide emissions are low. Those emissions are low while driving around it mind you. What the numbers were for producing the car remains out of the equation but hey, what else is new in Brussels?
Some products even find themselves banned from the market for not being green enough. Incandescent light bulbs had to go. They were replaced by CFL. A CFL is indeed more efficient in use but what about the environmentally unfriendly mercury inside? The industry claims the amount per bulb is small. With millions of CFLs worldwide in landfills, the amount becomes substantial. One clever company markets vintage incandescent light bulbs as heaters. Radiating photons aka light emissions and fitting into standard light sockets are a mere side effect. Check out heatball.de. Beating the system is such fun.

Of course our audio industry has been affected as well and some companies already took the measure. Sex and audio really never were a very good match. The scarcely clad well-curved ladies did little good promoting high-end gear. Only a few brands used their services. Good riddance.


Now, audio is fun. And a sad if basic fact of life is that fun things get taxed and regulated to the hilt. When the audio industry remains one step ahead of busy regulators, we have perhaps a chance to set the rules for once and avoid being exposed to silly taxes. One thing is energy consumption. Except for class D, our hifi amplifiers are far from energy efficient. Class A amplifiers are downright space heaters. So are most tube-based designs whose exposed glass sheds heat on a constant basis. It won’t be long before a ban on such designs outlaws them and only amps with an Energy Star label will remain available. Possession and sales of tubes could well become illegal. We must act quickly.

We found some early examples of anticipatory greenified audio to use newspeak. First is KR Audio’s Kronzilla SX. This Czech amplifier uses the largest triode still in production, the T1610. This tube is able to put out around 40 watts but dissipates 150 watts. This can never be called energy efficient no matter the marketing slant. In the Kronzilla series of amplifiers at least two of these monster tubes are employed. The mono amps use four. Their heat dissipation is waste and as such much in conflict with our Dutch frugality, the alleged national character sometimes mistaken for plain cheapness. Cor Dekker, KR’s distributor in the Netherlands, applied frugality plus brainwaves to come up with a new concept. The Kronzilla's basic design is a hybrid of Mosfets assisted by the giant power triode. Cor reasoned why not split the hybrid into two parts connected by a switch? For non-critical listening the Kronzilla then only runs its output transistors. When the real deal is needed, the T-1610s switch in. When he presented his idea to KR’s technical designer Marek Gencev, it was greeted as not only good but very feasible. When co-owner Eunice Kron gave here blessing, the Kronzilla SX- Eco became fact - green in efficiency, frugal with regards to tube life.

A completely different approach is used by Franck Tchang’s ASI Grand Stereo and ASI Grand Mono transistor amplifiers. These giant machines are rated at 650wpc into 8Ω in stereo or 2.4kw in mono. When load impedance drops, they can deliver 1.800wpc/4.500w into 2Ω respectively. That is a ton of power particularly in class A. One would expect the heat sinks to get scorchingly ferocious at typical class A idle bias but in practice these amps don't approach lukewarm even at high levels. This hides the ingenuity of Milan Karan who made the amplifiers so fast that sliding bias became an option. With this technology the input signal is constantly monitored for dynamic content. Higher input levels necessitate an instantly higher draw on the power supply to become available at the output stage. By using very fast components and a clever circuit Milan manages to deliver power to his Sanken ring emitter transistors on time and only in the quantities needed. As a result there is hardly any energy wasted as heat even though these huge amplifiers are specified to be true class A designs.
Naturally green are class D amplifiers whose efficiency is 90% or higher. One of the leading companies developing high-end class D modules is Hypex where the well-known Bruno Putzeys oversees R&D. His highly successful UcD product line was recently complemented by the Ncore line.


With Ncore modules distortion factors and output impedance are even lower than before and load impedance has been improved as well. These new modules are alleged to outclass non-switching amplifiers at the very highest level whilst still adhering to all the classic benefits of class D. Soon we shall test this claim in a formal review.

Reviewing is always a lot of fun. We receive many boxes and ship many back. Manufacturers don’t always go the extra mile of custom-cut packaging materials where the exact shape of the device to be protected is cradled to a T. Often a load of loose Styrofoam or other messy filler gets dumped into the box. Retrieving something from such a container floods the floor in Nibbits-type junk. It gets even worse with brittle Styrofoam. The slightest damage to that causes a hailstorm of ultra-light Styrofoam pebbles. Vacuuming them away is not easy. Static charge sticks the darn pellets to almost anything. But there's a more profound pain. These plastics are all made from a styrene compound which is toxic. Once in the environment it lasts for almost eternity though polystyrene (Styrofoam is a brand name) is otherwise 95% air.


There’s hope though. We encourage audio manufacturers to follow new developments. We recently received a shipment in a box filled with green (!) loose-fill material. On top of the filling was a note stating that the stuff was bio-degradable. Big deal we thought, it would probably take a year to degrade to half its volume. But no as we read on, we could put all the green cushions in the bathtub and rinse them down. The stuff would dissolve and disappear down the drain without any environmental harm. It’s made of a natural starchy base (perhaps corn?). It was fun to play in the bathtub and the stuff did dissolve quickly and completely as promised. Manufacturers, please think of the environment before you are forced to by changed legislature - and look into environmentally friendly packing materials while you're at it...