Why has JRDG adopted high speed and highly regulated switch mode power supplies, and has abandoned classic toroidal and linear power supplies instead?

Jeff Rowland is proudly committed to creating green products. Employing cool running, super efficient, and incredibly quiet switch mode power supplies is part of Roland’s innovative green product strategy. Jeff Rowland is one of the very 1st designers in the high end audio industry to feature extremely high speed, and very highly regulated switch mode power supplies in reference level products, like the Model 625 class A/B stereo power amplifier, the Criterion and Corus linestage preamplifiers, the Model 301 monoblock power amplifier, and the Continuum 500 integrated amplifier.

For several years already, advanced switch mode power supply technology has shown enormous potential for ‘mission critical’ applications, where exceptionally high reliability, very low mass and correspondingly high power density, ultra-fast response, very low conducted and radiated noise, and cool operation are required. This is the reason why high speed and highly regulated switch mode power supplies have been developed for the aerospace, defense electronics, medical, communications and industrial controls industries, where they enjoy an existing install base of millions of units worldwide.

The AC switch mode power supply in the Criterion reference linestage for example, utilizes a small regulator module within the control chassis that is unique to the audio industry. This module, created for military and aerospace applications by a renouned British company,  is so compact that it easily fits on the palm of an average hand, yet it is capable of delivering a full 100W of power. This power supply modules results in the most musical AC based pre-amplification currently available, surpassed in performance only by the Criterion’s very own DC rechargeable batteries power supply.

In comparison to traditional linear or toroidal power supplies used in most high end audio amplifiers and preamplifiers, JRDG’s highly regulated switch mode power supplies feature:

Compact size: There is no need for comparatively bulky, heavy, inefficient power supplies. In comparison to other power supplies that occupy a large portion of an amplifier or pre-amplifier, the Model 625 integrated switching power supply modules occupy a very modest space. This results in much lower heat generation and shorter electrical paths, and also avoids the need for sonically obtrusive devices such as cooling fans that would inject unwanted RF/EMI noise into the system through their electromagnetic motors. 

Highly efficient: The highly regulated switch mode power supplies inside JRDG products are incredibly efficient. The model 301 monoblock amplifier for example, converts up to 98% of the AC power drawn from the electric mains into music. This yields much cooler operation temperature, very little wasted electricity, lower energy bills, and a much better ratio of power delivered to the system's loudspeakers.

Very Fast switching operation: Switch mode power supplies used in many audio products operate at speeds of only up to 50 kHz. JRDG switch mode power supplies are able to operate at blazing speeds in excess of 1 MHz, enabling amplifiers and preamplifiers to greatly enhance control of musical signals, because of their high degree of power regulation, while making other supplies seem slow and ponderous by comparison.

Reduced RF and EMI radiation: Keeping RF noise and EMI interference low in a power supply is a fundamental step for obtaining cleaner, more transparent reproduction and superior dynamic response from an amplifier or preamplifier. Because of their small size, the modules utilized in JRDG products generate far less RF and EMI than other switch-mode supplies, offering greater clarity, better dynamic range, and greatly enhanced dynamic transient response.

Fully regulated switch-mode supply: The pure DC provided downstream to the amplifier or preamplifier is fully regulated, providing a steady and constant source of power, regardless of AC line and loudspeaker load conditions. In addition, the full regulation of the switch-mode power supply in JRDG products is exceptionally efficient, generating very little heat in comparison to the inefficient traditional linear and toroidal power supplies that radiate large amounts of heat.

Ultra quiet operation: JRDG amplifiers and preamplifiers perform optimally with no change in output power, operating temperature, or sonic performance regardless of fluctuations in the supported AC input voltage. Since there are no large and bulky power transformers to saturate and consequently hum, vibrate, or buzz within the chassis, the performance of JRDG components is absolutely quiet under all AC line conditions at any supported voltage or frequency.  The end result is cleaner, clearer, faster, more musical and sensuously refined sound reproduction from a cool running, energy efficient, and truly green component.     

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Last Updated
24th of October, 2010

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