THE MclNTOSH C 33 SOLID STATE STEREO PREAMPLIFIER Reading Time: 43 Minutes Price $2.
VARIOUS REGULATORY AGENCIES REQUIRE THAT WE BRING THE FOLLOWING INFORMATION TO YOUR ATTENTION. PLEASE READ IT CAREFULLY. WARNING: TO PREVENT FIRE OR SHOCK HAZARD, DO NOT EXPOSE THIS UNIT TO RAIN OR MOISTURE. The Mclntosh you have purchased is a Model C 33. It has a serial number located on the rear panel of the chassis. Record that serial number here: Serial Number The model, serial number and purchase date are important to you for any future service.
Your C 33 Stereo Preamplifier is designed to perform to its specifications for many years. If you have any questions, please contact: Contents CUSTOMER SERVICE Mclntosh Laboratory Inc.
Introduction The Mclntosh C 33 is a super quality, high performance Stereo Preamplifier. Its design has been governed by insistence on great flexibility, versatility, low distortion and high performance with long life. The C 33 provides many features for your listening enjoyment. They include: 1. 2. a dual preamplifier system with separate listen and record program lines, which allows listening to one program source while recording from a different independent program source.
-3- MclNTOSH C 33 STEREO PREAMPLIFIER One Channel Shown, Other Channel Identical Simplified Block Diagram
from the top. With adequate ventilation the instrument can be mounted in any position. The recommended minimum space for installation is 15 inches (38.1 cm) deep, 17 inches (43.2 cm) wide, and 6 inches (15.2 cm) high. To install the instrument in a Mclntosh cabinet, follow the instructions that are enclosed with the cabinet. For any other type of installation, follow these instructions: 1. Unpack from Carton Open the carton and remove the PANLOC brackets, hardware package, and mounting template.
net panel; the short flange is mounted against the front (face) of the cabinet panel. The screws pass through the PANLOC bracket flange, the cabinet panel, and then through the mounting strips previously mounted. use a file to square the corners and smooth any irregularities in the cut edges, 5. Install the Mounting Strips In the hardware package you will find two mounting strips and two sets of machine screws. For panels that are less than ½ inch (12.7 mm) thick, use the ¾ inch (19.
-6- Simplified ConnectingDiagram
How to Connect Rear panel input jacks are provided for 2 stereo turntables, PHONO 1 and PHONO 2; a stereo tuner, TUNER; 3 stereo tape recorders, TAPE 1, TAPE 2, and TAPE 3; and an auxiliary high level source, AUX. the Right TAPE 1 INPUT jack. Connect a second and third recorder in the same manner to the TAPE 2 INPUT and TAPE 3 INPUT jacks. Front Panel Tape Recorder Jacks: TAPE 3 recorder input and output connections are also available at the TAPE 3 IN-OUT jacks on the front panel.
Two stereo power amplifiers or two delay units may be connected in the same fashion to the OUTPUT 1 and OUTPUT 2 jacks. Audio output signal is supplied to these jacks only when the front panel pushbutton SPEAKER/OUTPUT 1 and/or 2 pushbuttons are pushed. This arrangement is useful for large systems where separate amplifiers and loudspeakers are used at distant locations. minal closest to the C 33 ground terminal. Connect the right plus lead to the red OUTPUT R terminal.
TAPE RECORDER 2 FM ANTENNA TUNER TAPE RECORDER I APE T RECORDER 3 AC POWER TO TAPE RECORDERS, TUNERS, POWER AMPLIFIERS. TOTAL OF 1200 WATTS.
MAIN SPEAKERS CUSTOM ENVIRONMENTAL EQUALIZER (FOR M A I N SPEAKERS) NOISE REDUCTION PROCESSOR PLAYBACK RECORD CONNECTIONS FOR POWER AMPLIFIERS AND LOUDSPEAKERS USING MAIN SPEAKERS AND ENVIRONMENTAL EQUALIZER. ALSO SHOWN FOR REMOTE SPEAKERS USING SEPARATE POWER A M P L I F I ERS AND CONNECTIONS FOR AN EXTERNAL NOISE REDUCTION SIGNAL PROCESSOR.
TO AC LINE REMOTE SPEAKERS (CONTROLLED BY SPEAKER 2 PUSHBUTTON) MAIN SPEAKERS (CONTROLLED BY SPEAKER 1 PUSHBUTTON) TIME DELAY UNIT CONNECTIONS FOR POWER AMPLIFIERS AND LOUDSPEAKERS USING OPTIONAL SCR-2 SPEAKER CONTROL RELAY. CONNECTIONS ALSO SHOWN FOR TIME DELAY UNIT AND MONITOR AMPLIFIER LOUDSPEAKERS. THE SPEAKER/OUTPUT 1 PUSHBUTTON WILL TURN ON AND OFF THE MAIN SPEAKERS AND THE TIME DELAYED PROGRAM. IF THE SCR 2 IS NOT USED THE PUSHBUTTON WILL TURN ON AND OFF ONLY THE TIME DELAYED PROGRAM.
Using the Front Panel Controls right output circuits. LISTEN AND RECORD SELECTOR SWITCHES R TO L&R: Connects the right input to both left and right output circuits. The LISTEN input selector switch is located at the upper left on the front panel. This is used to select the input for the LISTEN program line. The LISTEN program line feeds the main output for the system power amplifier and loudspeakers. The RECORD input selector switch is located at the lower left on the front panel.
Problem Deep bass to weak All bass weak Voice reinforcement Hum on program Violins, trumpets dull Cymballs not audible Equalizer Correction Raise 30 Raise 30 and 150 Lower 150 and raise 500 Reduce 30 and 150 Raise 1500 Raise 10 K range. It can be used for making tape recordings or for listening to background music. The Compandor can be switched to either the record or listen lines. In this way you can make your own recordings using compression and then play them back using expansion.
(usually between 1.2 and 1.5). Now switch the expander on and off. A change in the average listening level will usually be heard at this time. Adjust the LEVEL MATCH control until the average listening level matches as closely as possible when the expander is on and off. After this adjustment you will notice that with the expander on, loud passages will be louder and soft passages including noise will be softer. a. Select the LISTEN input. b. Increase the VOLUME to a satisfactory level. c.
Using the Pushbuttons light will be off. When the pushbutton is in, the LF FILTER is in the circuit and the red light will be on. The filter is effective for all frequencies below 50 Hz and attenuates at the rate of 12 dB per octave. Use it to reduce undesirable low frequency noise such as rumble or mechanical feedback. COMPANDOR The COMPANDOR pushbutton connects the compandor to either the listen or the record program line.
ed such as rear channel reverberation units, color displays, etc. For example Output 1 or 2 can be connected to a reverberation device and then to the C 33 monitor amplifier and a set of rear loudspeakers. (The monitor amplifier switch must be in the EXTERNAL position.) Rear channel reverberation can then be switched in and out without the need for an extra amplifier.
Top Panel Information and Secondary Controls COMPANDOR Operation of the LEVEL MATCH and SPEED controls is explained on page 13 under the Compandor System description. MANUAL switch must be set in the MANUAL position. The red POWER pushbutton must be used instead. In the event you are using two record players, adjust the SENSITIVITY control as described above with both turntables connected to the C 33 green outlets. Start with both turntables switched off, and then one at a time switched on.
Performance Limits and Ratings PERFORMANCE LIMITS Performance limits are the maximum deviation from perfection permitted for a Mclntosh instrument. We promise you that when you purchase a new C 33 from a Mclntosh franchised dealer, it will be capable of or can be made capable of performance at or exceeding these limits or you can return the unit and get your money back. Mclntosh is the only manufacturer that makes this statement.
Performance Charts RESPONSE IN: AUX; OUT: MAIN LF AND HF FILTERS RESPONSE IN dB FREQUENCY 0 -4 -8 -12 MONITOR AMPLIFIER -16 -20 10 100 1K FREQUENCY IN HERTZ 10K 100K RESPONSE IN dB 20 15 LOUDNESS CONTROL RESPONSE FOR VARIOUS CONTROL POSITIONS 10 5 0 20 100 1K FREQUENCY IN HERTZ 10K 20K EQUALIZER FREQUENCY RESPONSE CONTROLS SET AT MAXIMUM AND MINIMUM RESPONSE IN dB 20 10 0 -10 -20 20 100 1K FREQUENCY IN HERTZ RESPONSE IN dB 20 10 0 RIAA EQUALIZATION CURVE -10 -20 2
HARMONIC DISTORTION IN PERCENT PHONO HARMONIC DISTORTION AT 2.5 VOLTS OUTPUT ,05 .04 .03 02 .01 0 20 100 1K FREQUENCY IN HERTZ 10K 20K 11 12 HARMONIC DISTORTION IN PERCENT -04 .03 .02 HARMONIC DISTORTION IN: AUX; OUT: MAIN .01 0 2 3 4 5 6 7 8 10 9 11 12 INTERMODULATION DISTORTION IN: AUX; OUT: MAIN INPUT FREQUENCY: 60Hz & 7kHz RATIO: 4:1 INTERMODULATION DISTORTION IN PERCENT RMS OUTPUT VOLTS .04 .03 .02 .
HIGH LEVEL INPUT VOLTAGE NEEDED FOR LEVEL MATCH 2.0 1.8 1.6 1.4 1.2 1.0 COMPANDOR LEVEL MATCH RANGE .8 .6 .4 .2 0 MID ROTATION CCW CW LEVEL MATCH CONTROL POSITION 60 50 OUTPUT (dB) 40 COMPANDOR EXPANSION AND COMPRESSION CHARACTERISTICS 30 20 10 MAXIMUM HIGH LEVEL INPUT IN VOLTS 12 96 11 88 10 80 9 72 8 64 7 56 6 48 5 40 4 32 3 24 2 16 1 8 0 0 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 RATIO CONTROL POSITION -21- 1.9 2.
Technical Description vent cross talk between inputs. The FET "on" resistance is very low which prevents distortion. The switching transistors are located right at the input jacks, so that signal wiring is kept to a minimum. This eliminates cross talk and noise problems. The simplified block diagram on page 3 and the detailed block diagram on page 24 show how the C 33 internal circuits are arranged.
tional amplifiers are arranged in circuit configurations that are equivalent to five series tuned circuits, each at one of the equalizer frequencies. These series tuned circuits are inserted via control potentiometers into either the input circuit or feedback circuit of the equalizer amplifier. This provides a boost or cut capability of 12 dB for each equalizer band of frequencies. A pushbutton switch allows the equalizer circuit to be switched from the Listen program line to the Record program line.
Block Diagram MclNTOSH C 3 3 STE -24-
REO PREAMPLIFIER -25-
MclNTOSH LABORATORY INC. 2 CHAMBERS ST., BINGHAMTON, N.Y. 13903-9990 607-723-3512 The continuous improvement of its products is the policy of Mclntosh Laboratory Incorporated, who reserves the right to improve design without notice. Printed in U.S.A.
