Carver C 2 Owners Manual

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Model C-2

Stereo Preamplifier

OWNERS MANUAL

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TABLE OF CONTENTS

INTRODUCTION . PAGE
Notice ........................... ' ................. 3
Unpacking ......................................... 3
Caution ........................................... 3

INSTALLATION ...................................... 3
Rear Panel Connections .............................. 4
Phone Moving Magnet Inputs .......................... 4
PhonoMoving Coil Inputs ............................. 4
Ground ........................................... 6 -
Tunerlnputs ...... 6
Aux Inputs ......................................... 6
Tape Inputs ........................................ 6
External Processor Inputs ............................. 6
External Processor Outputs ........................... 7
Tape1andTap920utputs ............................ 7
PrearrplrfierGain Change ............................. 7
MainOutput ....................................... 7
Fuse . . . ..' ........................................ 7
AC Sockets ........................................ 7
AC Una Cord ....................................... 7

' THE FRONT PANEL:

PREAMPUFIER CONTROLS ........................... 7
Power ............................................ 7
Headphones ....................................... 8
VolumeandBalanoe ................................. 8
Input Selector ...................................... 8
lntrasonic Filter ..................................... 9
Tape Monitor: Tt.T2 ................................. 9
External Processor ................................. '. 9
StereoIMono (Mode) ................................. _ 10
Tone Controls ...................................... 10
Mute ............................................. 10

IN CASE OF DIFFICULTY .............................. 10
Hum ............................................. 10
Radio-Frequency Interference ......................... 11
Problem Solving With Hints ............................ 11

SPECIFICATIONS .................................... 12

Warranty .......................................... 12

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INTRODUCTION

Congratulations on your purchase of the Carver 0-2. We believe its
sophisticated engineering and meticulous craftsmanship will provide you
with many years of listening enjoyment.

The 0-2 is a high-performance console preamplifier with precise RlAA
phono equalization. low distortion. high slew rate. wide dynamic range. and
a high degree of control flexibility.

NOTICE TO PURCHASER

IT IS OKTO BEGIN USING YOUR NEW 02 WITHOUT FIRST
READING THIS OWNERS MANUAL YOU CANNOT HURT IT. AND IT
CANNOT HURT YOU. if you have previous experience with stereo
components. you probably can complete the input/output connections and
make normal use of the basic preamplifier functions without special
instructions.

This manual was prepared with unusual thoroughness and care, and we-

recommend that you read itin its entirety at your earliest convenience. You
will find that even some of the 'conventional' parts of the 0-2 are in fact not
conventional at all.

We also recommend that you record the following iniomtation here, for
possible future reference:

02 Serial No.:

Purchase Date:

Store Name and Address:
UNPACKING

The 0-2 is not fragile. but it is a precision instrument and deserves to be
handled with care. As you unwrap it. we recommend that you return all
packing materials to the carton and then store the carton in a convenient
place. it has been designed to provide the safest protection for the 0-2 and
should be used whenever you ship the unit. 9.9. when moving to a new
address or returning the unit for servicing.

CAUTION NOTICE

To prevent a fire or shock hazard. do not expose this unit to moisture or
rain. it it accidentally becomes wet. disconnect its AC power cord until the
unit is thoroughly dry, inside and out.

Before connecting or disconnecting cables. unplug the C-2's AC power
cord or switch off the power to each component in the stereo system -
especially the power amplifier. If the power amplifier lacks an on-olf switch.
unplug its own power cord.

Do not remove the top or bottom cover of the 0-2. There are no user-

serviceable parts inside. Refer all servicing to qualified personnel;
unauthorized servicing may void the warranty.

INSTALLATION

The C-2 is an all-solid-state design and may be operated horizontally.
vertically. or at any angle. It has no special ventilation requirements. but it
should not be operated in a totally enclosed cabinet

Its location relative to other stereo components is generally not critical. with
one exception: the power transformers of some power amplifiers radiate a
severe external hum field. so it may not be practical to place the preamp
adjacent to or stacked with the power amp. (Such power amplifiers should
also be kept away from turntables. phono signal cables. and the playback
heads of tape recorders.)

Typically the preamp must be located close to the tumtabie in orderto keep
phono signal cables short; begin by locating the tumtabie on a stable.
vibration-free surface and then arrange the preamp and other system
components in convenient locations nearby.

On the other hand. in many systems it would be a worthwhile convenience

if the preamp could be located within arms length of the prime listening

seat. while keeping the turntable on a stable vibration-free shelf. Often this

can be done simply by using extra-long connecting cables. Such cables

increase the risk of hum and rarfio interference; if neither problem arises.

then the remaining concern is the capacitance of the cable as it relates to

the 'load' requirements of your phono cartridge. if its manufacturer
specifies that the cartridge should be used with a relatively low value of

load capacitance (9.9. 250 pF or less). then you can't use a long cable

unless it is of special low-capacitance design. With cartridges designed for.
a load capacitance of 400-500 pF. orwith low-inductance cartridges. which
are insensitive to cable capacitance, you may find that you can use long

connecting cables with no adverse effect on the sound. For reference. the
lowest-capacitance audio cables typically add about15 prer foot of cable
length; garden-variety audio signal cables may add as high as 50 or 100 pF
per foot of length.

USING YOUR C-2:
A QUICK OVERVIEW

Doubtless you are eager to begin using the 0-2. Therefore this chapter
provides a very condensed summary of the essential information that you
need to hook up and use the preamp. without waiting to read the entire
owners manual.

NOTE: The 0-2 is different from most preamplifiers in many not-so-
obvicus ways. In order to getfull benefit from the original design of the 02.
you owe it to yourself to read the rest of this manual at your earliest
convenience.

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This can be eliminated. it desired. by installing 'shorting plugs' in the
unused jacks on the rear panel. (00 NOT install shorting plugs in unused
OUTPUT jacks. This would short-circuit the output of the preamplifier.)

INFRASONIC FILTER

The selected input signal passes through an inlrasonic filter which has no
effect on the audible tonal balance oi most recordings (even those with
prominent deep bass) but rolls oil rapidly at frequencies below 20 Hz.
When the INFRASONIC FILTER switch is out. this filter is bypassed; when
the button is depressed the filter is engaged. It is a good practice to leave
the filter switched on permanently.

The filter's group delay. an unavoidable consequence of its rapid
inlrasonic attenuation, may produce a just-perceptible alteration of low-
frequency transient response. Butin general any audible effect ol the filter
will be beneficial. since reproduction ofinfrasonic signals yieldsnobenefit.
These unwanted signals include switching thumps. tum-on transients of
associated components. the thump produced in some FM tuners when
tuned pasta station. and the transient produced when the phono stylus
sets down in the groove. It reproduced at high gain through a powerful
amplifier. such signals can damage loudspeakers.

Phonograph output signals are also contaminated with strong inlrasonic
waveform components due to small and large disc warps. motor rumble
(especially in direct-drive units). acoustic feedback and other externally
induced vibrations sensed by the phono stylus. alloltheseamplilied by the
tone arm resonance (due to the stylus compliance interacting with the
effective arm mass). These signal components occur primarily in the
frequency range from2l-lzto ISszitnotstripped oflthe audio signal byan
effective infrasonic filter they will tend to waste amplifier power and cause
excess woofer cone motion, resulting in audible intermodulation distortion
(muddy basst .

Since the INFRASONIC FILTER is located in the preamp circuit ahead of
the tape outputs. it will also prevent low-frequency overload of recorrfings
by infrasonic contamination. However. it cannot remove anylowtrequency
switching thumps produced by the tape recorder itself: so if you have a
recorder which produces such thumps when going in orout of the playback
mode. reduce the setting of the VOLUMEcontrol until the recorders output
has stabilized.

MONITOR

TAPE 1 (T I). TAPE 2 (1'2) - There are two ways to listen to the playback
output from a tape recorder. One way is to use the MONITOR switch and
select either T1 or T2. This MONITOR switch permits the output from the
tape machine to be heard regardless ol the setting of the INPUT
SELECTOR. (It notape machineisconnected tothe inputjacks. or it one is
connected but not operating, then rotating the MONITOR switch away from
OFF will produce silence.)

The tape MONITOR switch controls only the selection of what signal is
heard. lthas no effectonwhichsignal is ledtothe preampsTAPE OUT
jacks for recording; that selection is controlled exclusively by the lNPUT
selector. '

The principal purpose of the tape MONITOR switch is to allowyou to listen
to tape playbacks and to monitor' the quality of new recordings while they
are being made.

The identity of that output signal depends on the recorders own controls. In
the playback mode. ofcourse. thesignal isreproduced from the tape. with
atwo-head recorder. when you putitinto the recording mode. normally the
recorders input signal will also bepresentatthe output tacks after passing
through the recorders Recording Level control and input circuitry. In the
case of a three-head recorder, when it is in the recording mode its output
signal will eitherbetheinputsignal orthe freshly recorded playback signal
from the tape. depending on the setting of the recorders own monitor
(T ape/Source) switch. So. with a three-head recorder you can instantly
compare the recorded signal with the incoming signal and detect any
recording faults.

Two special situations deserve mention (1) If you are using an external
'singie-pass' noise~reduction system with the recorder (9.9.. a Dolby or
DBX unit of the type which must be switched between recording and
playback modes). then the monitor output of the system during recording
maybean 'encoded' version ofthe input signal with asubstantially altered

. tonal balance. (2) If aDoIby-encoded FM broadcast is fed through a

recorder having a bunt-in FM Copy mode. then the recorders output may
be a decoded version of the broadcast In this case the TAPE MONITOR
switch will enable you to hear the decoded sound. Thus the uses ol the
MONITOR function are varied. but the operating rules are simple: To listen
to phonograph records. radio broadcasts. or program sources connected
to the preamp's AUXiliary inputs. leave the TAPE MONITOR switch
disengaged (OFF). You will hear the program source chosen by the input
Selector. To hearthe output from tape recorder #1. switch the MONITOR
to T1. To hear the output lrom tape recorder #2. switch the MONTIOR to
T2. As described earlier. the TAPE MONITOR switch (In conjunction with
the SELECTOR switch). chooses what signal you will listen to. The
selector switch chooses the signal which will appear at the preamp's Tape
Output iackslor recording. Again. the operation rules are simple. To copy a
tape from recorder #t to recorder #2. put the Input selectorto TAPE 1 and
set recorder #2 in the record mode. To copy a tape from recorder #2 to
recorder #1. put the Input selector to TAPE 2 and set recorder #1 in the
record mode.

EXTERNAL PROCESSOR

Any external signal-processing accessory. such as a graphic equalizer or
DBX disc decoder (tor processing playback signals onlll). can be
connected tothe EXTERNAL PROCESSOR input/outputiackson the rear
panel. and can be engaged or bypassed at will by means of the
EXTERNAL PROCESSOR switch.

Thus it you have a special loudspeaker equalizer connected tothesejacks,
you should depress the EXTERNAL PROCESSOR button to engage the
equalizer when listening to the speakers which require the equalization.
When listening to headphonesorto otherspeakers which don't require the
equalization. switch out the EXTERNAL PROCESSOR.

Ityou have no equipment connected to the External Processoriacks. or
have equipment connected but not operating. then depressing the
EXTERNAL PROCESSOR switchwill produce silence.