Jeff Rowland Design Group is not so much a business as a dedication--a dedication to a single, heartfelt idea, the production of electronic components capable of unveiling the rich, emotional tapestry of music in a personally involving way.
Such dedication carries with it the implicit responsibility of a wholly uncompromising approach to audio design. At Jeff Rowland Design Group, pride of craftsmanship shares equal footing with sonic innovation. The result is a product line that offers unrivaled musical revelation packaged in chassis designs of unparalleled beauty.
We trust that the end result of our nearly three-decade quest for musical truth is the creation of audio equipment of enduring value. More importantly, we hope our efforts can, in some small way, offer a key that assists listeners in unlocking the vast structure of emotion that is...music.
Power Supply Switch Mode Technology
Current Jeff Rowland Design Group products feature an innovative separate, high-speed “switch-mode” power supply, one of the first of its kind within the audio industry. This technology has previously been used within the communications, medical, defense electronics, and industrial control fields with an existing base of millions of units worldwide. The Model 10 and Model 12 power supplies utilize a pair of small regulator modules within each power supply chassis that are unique to the audio industry and are able to deliver a whopping 120 watts of power density per cubic inch.
These power supply modules are based on efficient zero-voltage, zero-current switching technologies, resulting in exceptionally high reliability, ultra-fast response, very low conducted and radiated noise, and cool operation to ensure the most musical amplification currently available. In comparison to the switch-mode power supplies used in other audio amplifiers, the Jeff Rowland Design Group Model 10 and Model 12 power supplies incorporate:
Smaller physical size. There is no need for comparatively bulky, heavy, inefficient power supplies. In comparison to other switching power supplies that occupy a large portion of the amplifier, the Model 10 and Model 12 modules occupy a space of 4.6 x 2.2 x 0.5 inches. This results in much lower heat generation and shorter electrical paths, and also negates the need for sonically obtrusive devices such as cooling fans or heatsinks that may ring.
Higher efficiency. The amplifiers utilize up to 40% more of the AC power drawn from your wall, meaning cooler operation, less wasted electricity, and a better ratio of power delivered to your loudspeakers.
Faster switching operation. Other amplifiers use switching supplies operating at speeds up to 50 kHz. The Model 10 and Model 12 Amplifier power supplies are able to operate at speeds in excess of 1 MHz, enabling the amplifier to offer greater control of musical signals and much better regulation while making other supplies seem slow and ponderous by comparison.
Lower RF and EMI radiation. Keeping RF noise and EMI interference low in a power supply is a fundamental step in obtaining cleaner, more transparent reproduction and better dynamic response from an amplifier. Because of their small size, the modules utilized in the Model 10 and Model 12 generate far less RF and EMI than other switch-mode supplies, offering greater clarity, better dynamic range, and dynamic transient response.
Fully regulated switch-mode supply. The pure DC provided to the rest of the amplifier 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 is exceptionally efficient, generating very little heat in comparison to traditional inefficient regulated power supplies that produce large amounts of heat.
Zero-voltage, zero-current switching. In other switching power supplies, the power transistor turns on and off with a lot of voltage present. This stresses the power supply and creates the need for greater filtering, shielding, and heat-sinking. In the Model 10 and Model 12, the transistors turn on and off at zero-voltage and zero-current, eliminating power supply stress, lower the amount of filtering and shielding required, reducing heat, and lowering RF interference.
The end result is cleaner, clearer, faster, more musical and realistic sound reproduction from a smaller, cooler, more energy efficient component.
Jeff Rowland Design Group Contact Information
Jeff Rowland Design Group