OW N E R ’ S M A N UA L M O D E L 3 1 2 S T E R EO A M P L I F I E R
TA B L E O F C O N T E N T S OW N E R ’ S M A N UA L M O D E L 3 1 2 S T E R EO A M P L I F I E R Introduction 2 Installation, Use & Care Product Features 3 Signal & Power Connections Package Contents 4 Specifications 14 Initial Inspection 5 Dimensions 15 Optional Adjustments 16 Maintenance & Cleaning Protection Systems © J e f f R o w l a n d D e s i g n Gr o u p 2 0 07. A l l R i g h t s R e s e r v e d .
INTRODUCTION OW N E R ’ S M A N UA L M O D E L 3 1 2 S T E R EO A M P L I F I E R Welcome to the Jeff Rowland Design Group “family” and congratulations on your purchase of what is unquestionably one of the world’s finest amplifiers. With its combination of features such as precision electronic circuitry, exceptional efficiency, and accurately machined chassis components throughout, your Model 312 Stereo Amplifier will offer you many years of musically satisfying enjoyment.
P R O D U C T F E AT U R E S OW N E R ’ S M A N UA L M O D E L 3 1 2 S T E R EO A M P L I F I E R • XLR input connectors for balanced system configuration. • Fully-balanced topology implemented in both input and output circuitry. • RCA input connectors for unbalanced system configurations. • Power Factor Correction (PFC) in power supply reduces AC line harmonic noise pollution and increases AC line power utilization to 99%. • Dual Speaker Output Terminals on each channel for bi-wiring applications.
PAC K AG E C O N T E N T S OW N E R ’ S M A N UA L M O D E L 3 1 2 S T E R EO A M P L I F I E R Ensure that all of the auxiliary components listed below are enclosed within the shipping carton and accessory box. Refer to the illustrations and verify that the proper components are included.
INITIAL INSPECTION OW N E R ’ S M A N UA L M O D E L 3 1 2 S T E R EO A M P L I F I E R Inspect the shipping container for damage. If any portion of the shipping container, packing material, amplifier, or accessories are damaged or missing, notify your dealer and the shipper (if a claim is to be made) immediately. unpac k in g Please Note: Many shippers require notification and inspection within 24 hours of delivery to determine the nature of damages incurred.
Maintenance & Cleaning OW N E R ’ S M A N UA L M O D E L 3 1 2 S T E R EO A M P L I F I E R All JRDG products are designed to provide a lifetime of enjoyment and listening pleasure. The Model 312 Stereo Amplifier is uniquely constructed from precision-machined 6061-T6 aluminum sub-assemblies, configured and dimensioned to maximize chassis strength and reduce vibration. Constrained mode damping materials have also been applied in several areas to further reduce chassis resonance.
If you have any questions about the care or cleaning of your Model 312 Stereo Amplifier, please contact your dealer or the JRDG factory before attempting to clean the chassis. The use of a cleanser or abrasive to clean the chassis that has not been approved by the factory will almost certainly damage the finish and will not be covered under warranty. NOTE: Cleaner/polish should be applied directly to the cloth and not the chassis. © J e f f R o w l a n d D e s i g n Gr o u p 2 0 07.
I n s ta l l at i o n , U s e & c a r e OW N E R ’ S M A N UA L M O D E L 3 1 2 S T E R EO A M P L I F I E R Locate the amplifier as close as possible to its final installation point. Allow access to the rear panel for making connections. The Model 312 Stereo Power Amplifier is extremely efficient and convection cooled, eliminating the need for fans or forced-air cooling. Multiple chassis can be stacked vertically, facilitating an upward flow of warm air currents throughout the vertical heatsink areas.
The JRDG Model 312 Stereo Amplifier has been designed to operate at the highest level of efficiency and performance in any normal operating situation; however, there are a few important use and care principles that must be kept in mind when operating the amplifier. • Do not expose the amplifier to rain, moisture, or excessively damp conditions. • The Model 312 Stereo Amplifier must not be modified in any way, other than according to official service bulletins from JRDG.
signal & power connections OW N E R ’ S M A N UA L M O D E L 3 1 2 S T E R EO A M P L I F I E R 1 A B C 2 10 P O B OX 7 2 3 1 , C O LO R A D O S P R I N G S , C O LO R A D O 8 0 9 3 3 U S A A D E - m ail : j rdg @ j e f f ro w land . co m F B D WWW. J E FF R O W L A N D .
Before attempting any system interconnection, please familiarize yourself with the front panel control of the Model 312 Stereo Power Amplifier. (1) FRONT PANEL STANDBY/POWER BUTTON: Press this button to operate the amplifier. Press again to place the amplifier in Standby mode. (2) FRONT PANEL STANDBY/POWER INDICATOR: This small, blue light will illuminate when the amplifier is operational.
signal & power Connections OW N E R ’ S M A N UA L M O D E L 3 1 2 S T E R EO A M P L I F I E R (D & E) LOUDSPEAKER OUTPUT: Unscrew the knob that secures the speaker output connectors on both the LEFT SPEAKER OUTPUT (E) and the RIGHT SPEAKER OUTPUT (D) and pull the securing block out far enough to allow access to the binding posts.
(F) 12V REMOTE TRIGGER: A 1/8” (3.5 mm) mini-plug connector is provided on the rear panel of the Model 312 for remotely switching the amplifier between Operational and Standby modes. When connected to another component with the proper circuitry, the amplifier standby function can be turned ON and OFF remotely in a custom installation, theater, or automated system setup.
S P E C I F I C AT I O N S OW N E R ’ S M A N UA L M O D E L 3 1 2 S T E R EO A M P L I F I E R Output Power, Continuous RMS watts, both channels driven 500 watts @ 8 ohms, 1000 watts @ 4 ohms per channel Frequency Response 5 Hz – 45 kHz, -3 dB @ 8 ohms Peak Output Current 40 amps Dynamic Range 120 dBa Load Impedance Range 2 ohms – 16 ohms Input Impedance 40k ohms THD + Noise, 0.1 watts – 500 watts, 4 ohms < 0.1%, Typically .01% @ 1 kHz CCIF Intermodulation Distortion, 19/20 kHz < .
DIMENSIONS OW N E R ’ S M A N UA L M O D E L 3 1 2 S T E R EO A M P L I F I E R 15.5 in. (394 mm) 16.7 in. (424 mm) 10 in. (254 mm) 18.3 in. (465 mm) 10.5 in. (267 mm) © J e f f R o w l a n d D e s i g n Gr o u p 2 0 07. A l l R i g h t s R e s e r v e d .
optional adjustments OW N E R ’ S M A N UA L M O D E L 3 1 2 S T E R EO A M P L I F I E R RISK OF ELECTRICAL SHOCK! WARNING: The instructions in this section are meant for qualified JRDG service personnel only; however, if you as an end user choose to attempt these adjustments yourself, JRDG cannot be held liable for any damage that may occur to your Model 312 Stereo Amplifier because of your actions.
P O B OX 7 2 3 1 , C O LO R A D O S P R I N G S , C O LO R A D O 8 0 9 3 3 U S A E - m ail : j rdg @ j e f f ro w land . co m WWW. J E FF R O W L A N D .
