Operating Manual Mark Levinson® Nº26 Dual Monaural Preamplifier Madrigal Audio Laboratories, Inc.
WARNING: TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK, DO NOT EXPOSE THIS APPLIANCE TO RAIN OR MOISTURE. CAUTION RISK OF ELECTRIC SHOCK DO NOT OPEN CAUTION: TO REDUCE THE RISK OF ELECTRICAL SHOCK, DO NOT REMOVE COVER. NO USER-SERVICEABLE PARTS INSIDE. REFER SERVICING TO QUALIFIED PERSONNEL.
Important safety instructions Please read all instructions and precautions carefully and completely before operating your Nº26 Dual Monaural Preamplifier. 1. ALWAYS disconnect your entire system from the AC mains before connecting or disconnecting any cables, or when cleaning any component. 2. This product is equipped with a three-conductor AC mains power cord which includes an earth ground connection. To prevent shock hazard, all three connections must ALWAYS be used.
From all of us at Madrigal Audio Laboratories, thank you for choosing the Mark Levinson® Nº 26 Dual Monaural Preamplifier. A great deal of effort went into the design and construction of this precision device. Used properly, it will give you many years of enjoyment.
Table of contents Front panel ................................................................................................... 1 Rear panel ................................................................................................... 3 Unpacking and placement ....................................................................... 5 Unpacking .............................................................................................. 5 Placement ....................................................
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0° 180° STEREO AUX 1 TUNER INPUT DEFEAT MADRIGAL AUDIO LABORATORIES 4 6 TAPE 1 TAPE 2 MONITOR 3 TAPE 1 CD TAPE 2 DUAL MONAURAL PREAMPLIFIER Nº 26 INPUT SELECTOR MONITOR SELECTOR 0dB 7 8 2 9 1 10 OFF RECORD SELECTOR OUTPUT LEVEL -1 0dB +1 -1 +2 -2 +3 -4 +5 -5 +2 -3 +4 -4 +1 -2 +3 -3 +4 -5 BALANCE 1 2 1 MONO 5 PHONO/ AUX 2 +5 BALANCE 2 7 3 4 5 6 6 Front panel 1 RECORD SELECTOR Selects between the program source (selected via the INPUT SELECTOR), and either
5 OUTPUT LEVEL Adjusts volume at the main outputs. The OUTPUT LEVEL control doesn't affect the tape outputs. Note: In some systems, particularly those with high-efficiency loudspeakers, high-gain amplifiers, and balanced interconnections, it's possible that you may hear some lowlevel sound through your loudspeakers even with the Nº26's OUTPUT LEVEL control set to OFF. If this occurs with all inputs, reduce the line gain (via the internal switches).
BALANCED OUTPUT R L 2 4 4 MAIN OUT TAPE 2 OUT TAPE 1 OUT 10 POWER SUPPLY INPUT OPTIONAL BALANCED INPUT DUAL MONAURAL PREAMPLIFIER Nº 26 DESIGNED AND MANUFACTURED IN U.S.A. BY MADRIGAL AUDIO LABORATORIES INC.
4 TAPE 1 OUT, TAPE 2 OUT Connect these outputs to the right-channel and left-channel tape inputs of your tape machine. 5 TAPE 1 IN, TAPE 2 IN Accept right-channel and left-channel signal leads from the tapeoutput connectors of a tape machine. These inputs can also be used with other line-level source equipment. These outputs are unaffected by the OUTPUT LEVEL control on the front panel of the Nº26. 6 POWER SUPPLY INPUT Accepts one end of the DC cable that connects the Nº26 to the PLS-226.
Unpacking and placement Unpacking Unpack your Nº26 Preamplifier and PLS-226 Power Supply, and keep all packing materials for future transport. Remove all accessories from the cartons. Carefully inspect the product for damage and flaws. If you find any, see your Mark Levinson dealer immediately. Placement Place the Nº26 as close as possible to the source equipment, thus keeping interconnect cabling as short as possible. It may be placed on a shelf or in a cabinet where it's convenient to operate.
Voltage selection The PLS-226 is factory-set (internally) for 100V, 120V, 200V, 220V, or 240V AC mains operation @ 50 or 60Hz. Make sure that the label on the bottom of the PLS-226 indicates the correct AC operating voltage for your location. PLS-226 bottom-panel label PLS-226 POWER SUPPLY DC OUTPUTS AC INPUT WARNING: BEFORE ATTEMPTING TO Voltage indication OPERATE THIS DEVICE, REFER TO OWNER'S MANUAL FOR PROPER OPERATING INSTRUCTIONS AND SAFETY PRECAUTIONS.
Set-up and installation Connectors and cables The Nº26 incorporates RCA-type and XLR-type connectors for audio signal input and output. The Madrigal-designed RCA-type connectors used for single-ended audio interconnection are a great improvement over ordinary RCAtype connectors. The gold-plated XLR-type connectors employed are of European design, and are made to professional standards.
Internal adjustments: cartridge loading The high-gain and low-gain phono options offer internally selectable cartridge loading via two four-pole miniature rocker switches, one for each channel. The high-gain and low-gain options have been factoryadjusted at 825Ω and 47KΩ, respectively. If you wish to change the factory-adjusted cartridge loading, see "Making the internal adjustments;" refer to the table below for the proper switch positions for each load setting.
Internal adjustments: varying the input capacitance If you wish to vary the input capacitance of the phono option to obtain the optimal value for a particular cartridge, a capacitor may also be inserted into the optional load terminals (see "Terminating the optional load" and "Making the internal adjustments"). Because the inherent input capacitance (all switches off) is in parallel with the optional load terminals, use the following formula to calculate the actual capacitor needed.
2. Using a 3/32" Allen key, remove the four 4-40 socket-head cap screws securing the end caps on the read of the Nº26's chassis. 3. Using a Phillips screwdriver, remove the four 4-40 screws securing the Nº26's top plate. Carefully slide the top plate to the rear and remove it. 4. Adjust the gain switches (using a ballpoint pen or similar instrument) and install optional loads as desired. 5. Reassemble the Nº26.
Care and maintenance To remove dust from the cabinet of the Nº26, use a feather duster. To remove dirt and fingerprints, we recommend isopropyl alcohol and a soft cloth.
Specifications The correlation between published specifications and sonic quality is unreliable. A list of numbers reveals virtually nothing. All technical measurements must be subject to qualitative as well as quantitative interpretation. Measurements of the Nº26 yield excellent results by any standards. However, only those specifications that apply to its actual operation are included here.
Dimensions 3/8" (9.5) 7/64" (2.5) Dimensions, Nº26, top view 1-1/8" (28.7) 3/4" dia. (19.1) 17-19/64" (439.4) 15-3/64" (382.0) 17-1/2" (444.5) 1-1/4" (31.8) 10-1/2" (266.7) 13-1/8" (333.4) Dimensions, Nº26, side view 2-35/64" (64.8) 2-3/4" (69.9) 7/16" (11.1) 7/64" (2.
3/8" (9.5) 7/64" (2.5) Dimensions, PLS-226, top view 1-1/8" (26.7) 3/4" dia. (19.1) 7-13/32" (187.9) 7-39/64" (193.0) 5-9/64" (130.6) 1-1/4" (31.8) 10-1/2" (266.7) 13-1/8" (333.4) Dimensions, PLS-226, side view 2-35/64" (64.8) 2-3/4" (69.9) 7/16" (11.1) 14 7/64" (2.
MADRIGAL AUDIO LABORATORIES 2081 South Main Street, P.O. Box 781 Middletown, Connecticut 06457 USA Telephone: (203) 346-0896 Fax: (203) 346-1540 ® is a registered trademark of Madrigal Audio Laboratories, Inc. 16 630031-1 ©1993 Madrigal Audio Laboratories, Inc. All rights reserved. Printed in U.S.A.
