Conrad-Johnson CA150 User manual

Conrad-Johnson Owner’s Manual:
CA150 Control Amplifier
conrad-johnson It just sounds right.

CA150 Owner’s Manual
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Thank you for selecting the CA150 control amplifier as the control
center and power amplifier for your audio system. The CA150
draws on three decades of research at conrad-johnson into the
reproduction of recorded music. The result is a control amplifier
with a remarkable ability to recreate the dynamics, textures,
tonalities, and ambience of live musical performances. With the
CA150, we believe that you will experience the excitement of
discovery in hearing more from your favorite recordings than ever
before.
At conrad-johnson, we expect our products to be a source of
satisfaction and of pride to their owners for many years to come.
Accordingly, circuit designs, parts and materials for all conrad-
johnson products are selected with a view to maintaining optimal
performance over the years. Our reputation for producing among
the industry's most reliable components is a natural consequence
of this engineering approach.
Although operation of the CA150 amplifier is quite straightforward,
please take a few minutes to read this manual for useful
information on its installation and operation.
In closing, we’d like to welcome you to the family of conrad-
johnson owners. We want you to enjoy your conrad-johnson
product to the fullest. To this end, our staff stands ready to answer
any questions you may have about the function and application of
your CA150, and to provide any needed service both during, and
after the warranty period. Our goal is to heighten your enjoyment of
recorded music.

CA150 Owner’s Manual
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imited Warranty For Conrad-Johnson Components
Conrad-Johnson Design, Inc. will provide service under warranty to
the original owner on products sold new in the United States for the
lesser period of three years from the date of purchase by the
original purchaser, or five years from the date of shipment to the
authorized conrad-johnson dealer. During the warranty period,
conrad-johnson will repair defective units without charge for labor
or parts (with the exception of vacuum tubes and batteries).
Exclusions. The following are not covered under this warranty:
a) Units that have been damaged by misuse, abuse, or
accident.
b) Units that have been modified, altered, or improperly
repaired by anyone not specifically authorized by conrad-
johnson design, inc.
c) Units not purchased from an authorized conrad-johnson
dealer in the United States for use in the United States.
d) Normal wear
e) Incidental or consequential damages are not covered under
this warranty. Some states do not allow the exclusion of
incidental or consequential damages, so this exclusion may not
apply to you.
Obtaining Warranty Service: To obtain warranty service, the unit
must be shipped, along with evidence of purchase, in factory
packing to conrad-johnson design (or designated service center)
with freight and insurance prepaid by the owner. After repair, the
unit will be returned with freight and insurance prepaid by conrad-
johnson design to any destination in the United States.
All implied warranties, including merchantability and fitness for a
particular purpose are limited in duration to the duration of this
express warranty. Some states do not allow limitations on the
duration of implied warranties so the above limitations may not
apply to you.
This warranty gives you specific legal rights and you may also
have other rights that vary from state to state.
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Conrad-Johnson products purchased outside the United States are
covered by warranty terms of the importing distributor in the
country in which the product was originally purchased, which may
differ from the terms set out herein. Importing distributors are not
obligated to provide warranty service for products originally
purchased outside their country. Conrad-Johnson will provide
warranty service for products outside the United States, but in
these cases, the customer must pay all shipping, handling and
customs costs both to and from our Service Department.
Questions about this warranty should be addressed to:
Service Department
conrad-johnson design, inc.
2800K Dorr Avenue
Fairfax, VA 22031
The conrad-johnson service department can also be reached by e-
mail at [email protected], by phone at 703-698-8581,
or by fax at 703-560-5360.
Service
If your conrad-johnson audio component requires service, repack it
using the original box and packing material and ship to the Service
Department address above. Boxes and packing materials can be
purchased through our service department if you no longer have
yours. Include with the unit a note describing the problem you are
having in as much detail as possible. It is especially important for
our technician to know if the problem is intermittent. If you want an
estimate of cost for out of warranty service, be sure to request it in
this note. Be aware that requesting an estimate will delay service
to your unit, as we will have to contact you for approval before
commencing service.
Registering The Warranty
Please return the enclosed card to the factory within 30 days of
purchase to register the warranty

CA150 Owner’s Manual
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nstallation
As is the case with any power amplifier, the CA150 dissipates a
significant amount of heat. To maintain proper ventilation, mount
the unit on a flat, hard surface, taking care that the ventilation holes
in the bottom are unobstructed. Maintain at least three inches of
clearance above the unit, and at least three inches on the sides.
The cabinet or shelf should be open at both front and back. For
more restricted installations, cooling fans are recommended.
The CA150 is protected by a thermal sensor that will shut the
amplifier circuit down in the event of overheating. If this happens,
the front panel display will read “-- --“ and the mute led will turn on.
When the amp has cooled sufficiently it will automatically power on
in the default mode (level set at 30, CD input selected).
All CA150s sold in the United States are configured for operation
on a 60Hz ac power line producing between 108 and 126 volts.
Export versions of the CA150 will have the correct operating
voltage and frequency clearly marked on the back panel of the unit,
near the ac power cord. In all cases, the actual line voltage should
be within + 5/- 10% of the nominal rated voltage.
Electromagnetic Interference (EMI)
Considerable care has been taken in the design of the CA150 to
minimize its susceptibility to radio frequency interference and other
forms of EMI. Choice of materials, physical layout, grounding
practice, and power supply design have all been specified with a
view to reducing the impact of electromagnetic fields on the
performance of this unit. Our primary goal, however, is the
accurate reproduction of recorded music in a normal home
environment. We have elected not to compromise this objective by
the application of heavy-handed RFI filters, or by using grounding
practices that reduce RFI at the expense of degraded audio
performance. We find that our approach works well, resulting in
only rare instances of EMI problems which could be treated locally
as needed, rather than compromising the performance of our
product in the 99.9% of installations where EMI is not a problem.
Care in installation can often avoid EMI induced problems.
Interconnect cables should be kept as short as possible (3 meters
or less), and shielded cable should be used (cable which has two
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CA150 Owner’s Manual
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center conductors, and a separate external shield connected at
only one end).
Physical location and cable “dress” can be an important factor in
minimizing hum pickup. Power (ac mains) cords should be dressed
to remain at least 4" (100mm) away from input/output cables.
onnection
SOURCES (PH/AUX1, TUNER, CD, VIDEO, AUX2): These high
level inputs are electronically equivalent. Connect the
corresponding source components to these inputs.
EPL1: A set of line-level inputs and outputs provided for
connection of external signal processors (e.g. parametric equalizer,
tone controls). These can also be used for the connection of a tape
recorder. In this case, connect the EPL OUT to the recording input
of your tape recorder, and the EPL IN to the output of your tape
recorder. The EPL IN connection can also be used as an additional
line level input.
THEATER: This is an external processor loop designed to
conveniently accommodate the addition of a surround-sound
processor (SSP) to a high-quality two-channel system without
compromising two-channel performance. Connect the front left and
front right channel outputs from your SSP to the THEATER input.
You can also connect the THEATER OUT to an input on your SSP,
allowing you to do matrix processing on selected two channel
sources. When THEATER is selected, the level controls are locked
to provide full power output with a 1.0 Volt input signal, and the
display reads “-- --“. Level and balance control is then
accomplished via your surround sound processor.
SUB OUT: This is a buffered line-level output intended for
connecting a subwoofer.
RIGHT OUTPUT, LEFT OUTUT: Five-way binding posts are
provided for connection of your loudspeakers, with correct spacing
to accept a standard "double banana" plug. They will also accept
spade lugs, bare wire, or pin connectors.
The two channels should be connected in correct "relative phase".
This means that when the same signal is applied to both channels,
the right and left channels speaker diaphragms will move
synchronously - in and out together. Terminals on speakers are
usually coded - one designated "C", "ground", "-" or black, the
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CA150 Owner’s Manual
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other designated "+" or red. "In phase" connection of the speakers
can normally be achieved by taking care to connect the wire from
the "+" amplifier terminal to the red or "+" coded terminal on each
speaker, and connecting the "-" terminal to the black or "-" coded
terminal on each speaker. In phase connection of the speakers can
be readily ascertained by ear. Listen to a recording of a solo
vocalist (use a mono recording if available). With the speakers in
phase the voice should be clearly focused between the two
speakers. With the speakers connected out of phase, the voice will
be diffused, with no identifiable source. Relative phase may be
reversed by switching the "+" and "-" leads at one speaker only.
ontrols
<power>: Press the switch labeled power to switch the CA150 on.
When first connected to ac mains, or after an interruption of power,
the CA150 will turn on in a default mode, with the level set at 30,
and the CD input selected. In subsequent sessions, as long as the
ac mains supply has not suffered a power outage, the unit will turn
on at the last used volume setting and input.
<mute>: Pressing the mute button will silence the CA150s speaker
and SUB WOOFER outputs, and set the level display to zero on
both channels. Pressing the mute button again will restore the
previously selected level setting.
<vol up>, <vol dn>: Level setting on the CA150 can be adjusted
in 1.0 dB increments. The level setting can be changed by pressing
the vol up and vol dn buttons on the front panel. Each time a button
is pressed, the level will move up or down one step in 1.0 dB
increments. If a button is pressed and held, the level control will
cycle through the steps at an accelerating rate. Balance can only
be set using the remote control and is also adjusted in 1.0 dB
increments.
<source>: Pressing the button labeled source will cause the unit
to step through the five source inputs (ph/aux1, tuner, cd, video,
aux2). The selected input will be indicated by an illuminated led.
<epl/thtr>: Pressing the epl/thtr button will cause the unit to step
from source through epl1 and theater. When source is selected,
the input selected by the source selector will be passed directly to
the volume control. When the EPL1 or THEATER inputs are
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CA150 Owner’s Manual
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selected, the selected source will first pass through the external
processor loop before being routed to the volume control. When
THEATER is selected, the level will be locked at a fixed gain so
that overall level and balance can be set by the surround sound
processor.
Remote Control
All operations of the CA150 can be controlled by the wireless
remote unit.
MUTE: Pressing the mute button will cause the main outputs to
mute and the level display to be zero. Pressing it again will restore
the last level setting. Pressing and holding the mute button for
more than three seconds will switch the CA150 into standby mode
(amplifier circuitry switched off). Pressing and holding the mute
button when the unit is in standby mode will switch it back on.
SELECTORS (PH/AUX1, TUNER, CD, VIDEO, AUX2): You can
directly access any of these inputs by pressing the associated
button on the remote.
EPLS (EPL1, EPL2): Pressing the EPL buttons inserts the
associated processor in the signal path. Pressing the button again
will re-establish a direct connection to the selected source.
Pressing the EPL2 button selects the THEATER input which locks
the level control to a fixed gain..
LEVEL (+, -): Duplicates the function of the front panel <vol up>,
<vol dn> controls.
BALANCE: Allows attenuation of either channel independently of
the other. Pressing the right balance button will reduce the left
channel level setting by one step. Pressing and holding the right
balance button will cause the left channel to cycle down through its
level settings at an accelerating rate. Pressing the left balance
button will attenuate the right channel in the same manner.

CA150 Owner’s Manual
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etting The Most From Your CA150 Control Amplifier
In a system of commensurate high quality components, the
conrad-johnson CA150 offers an unparalleled level of
sophistication and refinement in music reproduction. To get the
best performance out of any audio system, there are a number of
important details that must be attended to.
Absolute Phase
Musical notes are heard through the ear’s response to waves of
alternating rise and fall of air pressure. Musical transients are
almost exclusively positive: that is, the initial effect is a rise in
pressure. The ear is capable of distinguishing these positive
transients from the musically unnatural alternative of a negative
transient (an initial fall in air pressure). In terms of your stereo
system, these transients are created by your loudspeakers. If the
speakers respond to musical transients by first moving out, they
are creating a rise in pressure, and the system is said to be phase
correct. If they respond by moving in, they create a fall in pressure
and the system is said to be phase inverting. Each component in
the stereo system either preserves the phase of the incoming
signal, and is said to be phase correct, or inverts the phase and is
said to be phase inverting. It is unimportant whether an individual
component is phase correct or phase inverting, as long as the
system as a whole is phase correct. This will be the case if the
number of phase inversions is even (or zero).
The CA150 is phase correct (non-inverting). If your system has an
odd number of inversions, (for example, if you have a phase
inverting preamplifier) then you must add one phase inversion.
This is conveniently done by reversing the positive and negative
connections to your speakers (be sure to reverse both channels). If
you are not sure about the phase of every piece in your system,
you can establish correct absolute phase by careful listening.
When the system is in correct phase, transients will be noticeably
cleaner and more sharply defined. The effect is especially apparent
on plucked string sounds. A final warning - not all recordings are
phase correct (including some “audiophile” recordings), so listen to
several before concluding your investigation of absolute phase.
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CA150 Owner’s Manual
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The Importance Of Wires
Interconnect and speaker wires are an important element in your
stereo system. Interconnects are available which will permit a
reference quality system to blossom and fulfill its promise of
musical reality. Others will strangle the system to the point where it
becomes little better than average. To complicate matters, our
experience suggests that the choice of interconnects will be
system dependent - those that are top ranked on one system may
be a poor choice for a different system. Consult your conrad-
johnson dealer for recommendations for your specific system.
Performance Tip
Warm up the CA150 before listening: The sonic performance of the
CA150 improves noticeably as the unit warms up. The midrange
becomes more lucid, the highs smoother, and the soundstage
expands. The warm up period can be expected to last about fifteen
minutes.
Questions: If you have questions about the installation or function
of your CA150 do not hesitate to call Customer Service at (703)
698-8581.

CA150 Owner’s Manual
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pecifications
Power: 135 watts per channel RMS both channels driven into 8
ohms from 20Hz to 20KHz at no more than 1.0% total harmonic
distortion or intermodulation distortion.
Frequency Response: 20Hz to 20 kHz +0/-.3 dB
Hum and Noise: 100 dB below rated power output
Phase: phase correct
Input Impedance: 10 kOhms
Mechanical
Dimensions: 14.625"D x 19”W x 4.5”H
Net Weight: 33 lb net
Fuses
The CA150 power transformer is protected by a fuse on the ac
power line (F8, located in a compartment in the ac line-cord
receptacle mounted on the back of the amplifier), and by seven
separate internal fuses on the secondary circuits of the transformer
(F2, F4, F6) and on the positive and negative power supplies for
the output stages (F1, F3, F5, and F7). These fuses (F1-F7) are
located on the top of the pc board. A failure of any of these fuses is
a symptom of a more serious problem, and a competent service
technician should be consulted. In no event should fuses be
replaced with a value or type different than that originally supplied.
The correct fuse values and types are:
F1, F3, F5, F7 (B+/B- fuses): 3AG 4 Amp Fast-Blow
F2: (low voltage power supply): 3AG ¼ Amp Slow-Blow
F4, F6 (high voltage power supply): 3AG 3/8 Amp Slow-Blow
F8: 5x20mm 6.3 Amp T-type if configured for 100 or 120V:
5x20mm 3.15 Amp T-type if configured for 220 or 240V.
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