Conrad-Johnson MET1 User manual

Conrad-Johnson Owner’s Manual:
MET1 Multi-channel Enhanced-Triode Preamplifier
conrad-johnson It just sounds right.

MET1 Owner’s Manual 1
Thank you for selecting the conrad-johnson MET1 multi-channel
enhanced-triode preamplifier as the control center for your audio
system. The MET1 is designed to allow you to enjoy movie
surround sound and multi-channel music in a simple and direct
way, without compromising the two-channel performance of your
system. The MET1 is capable of remarkably faithful recreation of
the dynamics, textures, tonalities, and ambience of live musical
performances. 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 the MET1 has been designed to operate in an intuitively
apparent way, you will find useful information on its installation and
operation in this manual. Please take a few minutes to read the
manual to better understand the features and capabilities of your
MET1. Note that this unit is phase inverting. See the section
entitled “Getting The Most From Your MET1" for details on correct
hookup in your system.
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 MET1, and to provide any needed service both during, and
after the warranty period. Our goal is to heighten your enjoyment of
recorded music.

MET1 Owner’s Manual 2
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 which have been damaged by misuse, abuse, or
accident.
b) Units which 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 which vary from state to state.
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MET1 Owner’s Manual 3
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.
2733 Merrilee Drive
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

MET1 Owner’s Manual 4
nstallation
The first step in preparing your MET1 preamplifier for use is to
install the vacuum-tubes. To do this, remove the top plate of the
tube guard by removing the three socket-head screws using the
supplied hex-head screwdriver. The MET1 uses six type 8080
tubes. After checking the pin orientation, insert one tube in each
tube socket (the tubes are interchangeable). Next, fit two of the
included silicone rubber rings over each tube, spaced at roughly
1/3 and 2/3 distances. These rings will minimize the effects of air-
borne microphonics on the tubes. Finally, reinstall the tube guard.
Set Up
To maintain proper ventilation, mount the MET1 horizontally on a
flat, hard surface, and take care that the ventilation holes in the
bottom are unobstructed. Allow at least two inches of clearance
above the unit and keep the cabinet or shelf open at the back.
All MET1s 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 MET1 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 MET1 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. At the same time, however, our primary
goal is the accurate reproduction of recorded music in the normal
home environment, and 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 the approach we have taken has
worked extremely 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.
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MET1 Owner’s Manual 5
Care in installation can often avoid EMI induced problems. The
following practices should generally be observed in any
application, and will be especially important where EMI may be a
problem.
Interconnect cables should be kept as short as possible (3 meters
or less), and shielded cable should be used (cable which has two
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. The installation should situate the
preamplifier well away from the power amplifier, and power (ac
mains) cords should be dressed to remain at least 4" (100mm)
away from input/output cables.

MET1 Owner’s Manual 6
onnection
STEREO SOURCE CONNECTIONS: There are 3 line-level stereo
inputs labeled PH/AUX2, CD, and AUX1 for your convenience.
Connect your line-level stereo sources (CD, DCC, Mini-Disc, VCR,
tuner, cassette deck, phono preamplifier, etc.) to the input of your
choice on the rear panel.
MULTI-CHANNEL SOURCE CONNECTIONS: Your MET1 has
provision for two sets of multi-channel inputs, labeled DVD/MC1,
and MC2. These allow for the connection of two separate 6-
channel sources (e.g. DVD-A and SACD players). Each multi-
channel source is provided with 6 inputs, arranged in three pairs
labeled <Left Front / Right Front>, <Center / Subwoofer>, and
<Left Rear / Right Rear>. Alternatively, the other input can be used
as an additional stereo input –just make connections to the Left
Front and Right Front inputs.
TAPE RECORDER CONNECTIONS: The MET1 includes a stereo
pair of RECORD OUT connectors to provide for recording from the
stereo inputs. Connect to the inputs of your tape recorder.
AMPLIFIER CONNECTIONS:Be certain your power amplifiers are
all turned OFF, then connect to the MET1's 6-channel outputs.
TRIGGER OUTPUT: When the MET1 is switched on, these
terminals provide a dc voltage that can be sensed by the “trigger”
circuits used to switch on some power amplifiers. If your amplifier
employs such a trigger circuit, and you wish to switch it on and off
from the preamplifier, connect these outputs to the trigger input on
your amplifier. Observe the coded polarities (“+” and “-“).
CONTROL IN: A connection for wired remote control input. This
allows the MET1 to obtain its control instructions from an IR
receiver located on another unit, or directly from a wired system
remote-control panel. This connection accepts a mini-jack plug.
NOTE: while a plug is inserted into this connector, the IR receiver
in the MET1 will be bypassed and control signals only accepted
through the wired input.
CONTROL OUT: A connection for wired remote control output.
This output passes along remote control signals received at its
CONTROL IN connection or at the IR receiver if no plug is
connected to the CONTROL IN.
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MET1 Owner’s Manual 7
ontrols
The MET1 has two basic modes of operation: Listening Mode and
Set-Up Mode. In Listening Mode, you may listen to multi-channel
sources or to stereo sources. When listening to any of the three
stereo sources, an Ambience Retrieval Mode (ARM) is available
which will synthesize six-channel sound from a two-channel
source. When properly adjusted, ARM can create a very
convincing acoustical environment, especially on live recordings.
(We recommend adjusting the ARM settings so that the rear
channels are barely audible, only contributing a sense of space to
the playback, and the level of the center channel is well below the
left and right channels).
The Set-Up Mode is used to adjust the relative levels of the six
channels for multi-channel sources, and for ARM.
Note: All front panel and remote controls are “tactile” switches
which operate by pressing and releasing.
<power> (front panel only):Press the switch labeled power to
switch the preamplifier on. The MET1 uses a time delay auto-
muting circuit to suppress transients at turn-on and turn-off. All
outputs are grounded via relays for approximately 45 seconds after
the unit is turned on. During auto-muting, the selected input
indicator led will flash. Level and balance control functions are
disabled during auto-muting, but input selection can be changed.
The muting relay also grounds the outputs immediately at turn-off
or in the event of any power line interruption. After the completion
of auto-muting, the selected input indicator led will be lit steadily
and the level display will light. When the MET1 is turned off (by
pressing the power switch again), the selected input indicator led
will remain steadily illuminated.
When first connected to ac mains, or after an interruption of power,
the MET1 will turn on with default settings (after auto-muting), with
levels set at 50, and DVD input selected. In subsequent sessions,
as long as the ac mains 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 preamplifier
main outputs on all six channels (but does not affect the TAPE
outputs), and set the level displays to zero. Pressing the mute
button again will restore the previously selected level setting.
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MET1 Owner’s Manual 8
Pressing and holding the mute button on the remote for three
seconds will toggle the MET1 on and off.
<vol up>, <vol dn>: Level setting on the MET1 is achieved by
advanced level control devices adjusting all channel levels in 200
steps of .5 dB per step. The steps are numbered 0 through 99, with
0 being silence, and 99 being maximum volume. The second
decimal point on each display is used to indicate the half dB steps.
For example, after first turning the MET1 on, pressing level up
once will move the display from <50 50> to <50. 50.>, indicating a
.5 dB increase in level.
The level control adjusts all six channels up and down together in
Listening Mode, and with the Left Front channel selected in Set-Up
Mode. For the remaining five channels in Set-Up Mode, the level
control adjusts the level of the selected channel relative to the Left
Front Channel. The left display indicates the channel being
adjusted, and the right display indicates level of that channel in dB
above or below the Left Front Channel (the first decimal point is
illuminated to indicate that the channel being adjusted is set below
the level of the Left Front channel). As in Listening Mode, the
second decimal point is used to indicate .5 dB steps. As an
example, a display reading of <C 1.2.> would indicate that the
Center Channel is adjusted 12 dB below the Left Front Channel.
<balance>: In Listening Mode, these controls shift the balance to
left or right in increments of .5 dB. Both Front and Rear channels
are adjusted by alternately lowering one channel, then raising the
other, leaving the overall level virtually unchanged. Center and
Subwoofer outputs are unchanged. In Set-Up Mode, the BALANCE
controls select the channel that is being adjusted. When setup is
toggled on with one of the multi-channel inputs selected, or one of
the stereo inputs in ARM, LF is the initial setting. Pressing [>>]
steps forward through Center (C), Right Front (rF), Right Rear (rr),
Left Rear (Lr), Subwoofer (S) then back to LF. Pressing [<<] steps
through the sequence in reverse.
Channel offsets are retained in system memory as long as the ac
mains power is maintained. The settings will be lost if the unit is
unplugged or if there is a power outage. There are two separate
memory registers, one for the settings for your multi-channel
inputs, and a separate memory register for the settings for the
ARM setup. Typically, the LF, C, RF, RR, and LR channels are
adjusted for equal levels for the multi-channel sources, whereas
you will most likely want to attenuate the center and rear channels
in ARM mode.

MET1 Owner’s Manual 9
<setup>: This switch toggles the MET1 between Listen and Set-
Up Modes.
<arm>: Pressing the ARM switch with a stereo source selected
toggles between Stereo and Ambience Retrieval Mode. In
Ambience Retrieval Mode the Center, Subwoofer and Left and
Right Rear channels are derived from the Left and Right channels
of a stereo source. Note that ARM is not available on either of the
two multi-channel inputs.

MET1 Owner’s Manual 10
acuum Tube Replacement
The MET1 circuit employs six vacuum tubes, all 6C4/8080s. The
brands of tubes we supply have been chosen by first selecting
those brands which are known to be most reliable, then by
extensive auditioning of these acceptable brands with the final
choices being made solely on the basis of sonic performance. We
know of no vacuum tubes available which will improve the sonic
performance of your MET1. The tubes in your preamplifier have
been tempered by a controlled burn-in procedure that permits them
to perform for a greatly extended period without sonic degradation,
and then selected for minimum residual noise. Replacement tubes
are prepared and selected in the same way. Therefore, we highly
recommend that you purchase replacement tube sets from conrad-
johnson design.
We anticipate tube life to accommodate two to three years of
operation without degradation in normal use -if the preamplifier is
switched off when not in use. If the preamplifier is left on at all
times, tube life can be exhausted in a matter of a few months.
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MET1 Owner’s Manual 11
etting The Most From Your MET1
In a system of commensurate high quality components, the
conrad-johnson MET1 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 audio
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 MET1 is phase inverting. If your system has an odd number of
inversions, (for example, if the MET1 is the only phase inverting
unit in the chain) 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 all 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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MET1 Owner’s Manual 12
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 MET1 before listening: The sonic performance of the
MET1 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 MET1 do not hesitate to call Customer Service at (703)
698-8581.

MET1 Owner’s Manual 13
pecifications
Gain: 25.5 dB
Maximum Output: 6V rms
Bandpass:2Hz to more than 100kHz
Hum and Noise:100 dB below 2.5V output
Distortion at 1.0 V output: less than .1% THD or IMD
Phase:inverts phase of all inputs at main out
Ouput Impedance:200 ohms
Mechanical
Dimensions: 15.5"D x 19"W x 5"H
Net Weight: 27 lb net
Fuses
In addition to an ac mains fuse (F3) located in the IEC inlet socket,
the MET1 has individual fuses located on the main pc board
protecting each of its two power transformers (one for the tube
circuitry, one for the control circuits). 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 these fuses be
replaced with a value or type different than that originally supplied.
The correct fuse values are:
If configured for 100 or 120V:
F1 1/2 amp, slow blow
F2 1/4 amp, slow blow
F3 T800ma
If configured for 220 or 240V:
F1 1/4 amp, slow blow
F2 1/8 amp, slow blow
F3 T400ma
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