Manley Labs 16 X 2 Tube Mixer User Manual

OWNER'S MANUAL

MANLEY

16 x 2

TUBE MIXER

MANLEY

LABORATORIES, INC.

MANLEY LABORATORIES, INC.

13880 MAGNOLIA AVE.

CHINO, CA. 91710
TEL: [phone]
FAX: [phone]

http://www.manleylabs.com

email: emanley @ manleylabs.com

email: service @ manleylabs.com

CONTENTS

SECTION PAGE

INTRODUCTION 3

BACK PANEL & CONNECTING 4,5,6,7

FRONT PANEL 8,9

TECHNICAL DETAILS 10

TUBE BOARDS 11

OPTIONS 12

SPECIFICATIONS 13

ADJUSTMENTS 14

TROUBLESHOOTING 15,16

MAINS CONNECTIONS 17

WARRANTY 18

WARRANTY REGISTRATION 19

TEMPLATES FOR STORING SETTINGS 20,21,22

INTRODUCTION

THANK YOU!...

for choosing the Manley 16 x 2 TUBE MIXER. While there are plenty of choices in low budget mixers
and consoles in the $30K to $200K with a myriad of features, buttons, EQs, etc. there is very little available
that simply feature sonic quality and a minimum of knobs. This mixer is mainly intended for those who
use and love workstations and plug-ins but find the aspect of mixing digitally to be frustrating their efforts
to achieve the finished result they crave. Others, with huge expensive keyboard rigs have found that
inexpensive mixers are not up to the task or are the weak link in the chain. There are also engineers who
need to record live music with a portable system and also need the quality not generally associated with
semi-pro gear. The Mic Version and 8+8 Version are well suited for this.

This manual describes both the Mic Version, Line Version and 8+8 Version and any pictures will show
the 8+8 Version so that all 3 versions are explained. The channel electronics of both versions are almost
identical. The Mic Version adds a number of resistors on an eleven position Grayhill gold contact rotary
switch that set the gain of the first stage while the Line Version does not use these resistors and operates
at unity gain. The Mic Version also has switches for INSERT and Phantom Power not needed on the line
version plus a switch for Phase Reverse mostly useful on Mic inputs. The input stage is a high performance
low noise instrumentation amp that we use in Manley's custom mastering consoles.

The L&R summing amps are 100% tube and transformer circuits very similar to the make-up amps in the
Massive Passive. This provides the desired "warmth factor" and dynamic richness and headroom that
Manley is known for. Additional features include External and Tape Inputs, and a separate monitor path
with provision for two sets of speakers.

GENERAL NOTES

LOCATION & VENTILATION

The Mixer is designed to be mounted either in a rack or a table with a 8.75" x 17.25" rectangular hole. The
Manley 16 x 2 Mixer should be installed in a stable location with ample ventilation. It is recommended,
if this unit is rack mounted, that you allow enough clearance on the top of the unit such that a constant
flow of air can move through the ventilation holes.

You should also not mount the Massive Passive where there is likely to be strong magnetic fields such
as directly over or under power amplifiers or large power consuming devices. The other gear's fuse values
tend to give a hint of whether it draws major power and is likely to create a bigger magnetic field. Magnetic
fields might cause a hum in the mixer due to transformers and occasionally you may need to experiment
with placement in the rack to eliminate the hum. In most situations it should be quiet and trouble free.

WATER & MOISTURE

As with any electrical equipment, this equipment should not be used near water or moisture.

SERVICING

The user should not attempt to service this unit beyond that described in the owner's manual.
Refer all servicing to your dealer or Manley Laboratories. The factory technicians are available for
questions by phone [phone] or by email at <[e-mail]>. Fill in your warranty

card! Check the manual - Your question is probably anticipated and answered within these pages......

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THE BACK PANELS

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1) MAINS ON / OFF SWITCH. "0" indicates OFF, "1" indicates ON. This should be set to OFF or O before plugging in any cables.

2) VOLTAGE LABEL (ON SERIAL STICKER). Just check that it indicates the same voltage as is normal in your country. It should
be. If it says 120V and your country is 220V, then you should look inside the power supply and behind the Mains Switch is a "change-over
switch" which has the numbers 110 and 220. Use an appropriate sized flat blade screwdriver to set it for the correct voltage for your area.

3) IEC MAINS SOCKET. In the box your mixer came in, is the IEC MAINS CABLE that should be wired correctly for your AC power.
Connect the mating side here and the plug to your AC power at the wall. This is all pretty normal with most audio gear.

4) POWER CONNECTOR. The thick captive cable from the back of the mixer gets connected here. Rotate it to align it properly then
the ring screws clockwise about a half turn to lock into place. This cable carries all the various power supply voltages to the mixer. Power
should be OFF while connecting and disconnecting this big cable and should be OFF for about 5 minutes before disconnecting to allow
the the power supply to discharge. It carries 350 volts DC for the tubes which can potentially arc pins and shorten their life or if touched
by fingers give a nasty shock or burn but the current is low and non-lethal. The large pins carry 12 volts DC for tube filaments and for LEDs
and Relays. These are higher current lines. Multiple redundant pins are used for other supplies for reliability and lower resistance.

One pair of pins carry 48 volts DC used for Phantom Power which will be on even if the power switch on the front panel of the mixer is
off. It is also used for that same front panel power switch to turn on relays that turn on the other volts. In other words, there are two power
transformers. There is a little one for the 48 volts which draws almost no power, and a rather big one for most of the mixer. The little one
is used to remote control the big one and turn on the bulk of the power supply. It also means that the bulk of the power supply can't be turned
on unless the mixer is attached via the Power Connector . This certainly makes connecting it safer but always have power switches turned
off before connecting it and, again, let the supplies discharge for at least 5 minutes before disconnecting.

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13 14 15 16 17 18 19 20

5) MIX BALANCED OUTPUT. Left and Right MIX outputs intended to feed a 2 track tape
machine, DAT or A to D converter. These are transformer balanced Pin 2 hot. This is the mix of all
16 channels plus EXT inputs. The MIX control is the final level control for these outputs. All
outputs MUTE during power up/down or if the MIX MUTE button is selected.

6) MIX UNBALANCED OUTPUT. Left and Right MIX outputs intended to feed a 2 track tape
machine, DAT or A to D converter. These are transformerless unbalanced tip hot. In general one can
use these to drive a balanced input or unbalanced input. The ring of the TRS jack is grounded via a
resistor that provides an impedance equal to the tip which ensures good common mode rejection. It
is possible that either the balanced and especially the unbalanced output may be capable of
overdriving the input of the receiving device due to the extreme headroom that a good tube
linedriver can provide (+37 dBu !). Either the balanced or unbalanced outputs can be used to chain
mixers for twice as many channels but the unbalanced TRS allows for simpler wiring into the next
mixers EXT inputs. SOLO chaining is done by connecting a wire from the SOLO terminals.

7) MONITOR XLRs. These XLRs are the MAIN MONITOR sends intended to feed power amps or
powered speakers. Wired unbalanced pin 2 hot but balanced Z to allow connections to balanced or
unbalanced inputs. These MUTE when MINI or MONITOR MUTE is selected and during a power­up and power down delay to prevent thumps into the speakers.

8) MINI MONITOR TRS. These jacks are the MINI MONITOR sends intended to feed power amps
or powered speakers. Essentially they allow one to use two sets of speakers or more convenient
cables. Wired unbalanced TIP hot but balanced Z to allow connections to balanced or unbalanced
inputs. These MUTE when MINI is not selected or MONITOR MUTE is selected and during a
power-up and power down delay.

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9) PHANTOM POWER. This switch is for the 48 volts needed for most solid state condensor mics.
It is not generally needed for tube mics, dynamic mics, ribbon mics and in some cases may be
harmful to some old vintage ribbon mics. Each switch is for a bank of 4 channels (1-4, 5-8, 9-12, 13-

16) and is a LOCKING TOGGLE which needs to be pulled to switch. This is a safety feature to
prevent huge pops from hurting speakers and sensitive ears. Mic signals are usually 1/100th of a
volt and phantom is 48 volts so a sudden change from switching phantom on or off can make a
horrendous thump. This can also happen if one plugs in a mic or mic cable or patch when phantom is
on. Try to get in the habit of turning down the channel and/or muting the Mix and Monitor to prevent
surprises and blown speakers. Also keep in mind, that slightly flaky mic cables or patch points may
seem much worse with phantom on. Phantom power may still be on even if the front panel power
switch is off because it is also used to remote control the main supply relays.

10) MIC CHANNEL INPUTS. These are COMBI jacks that allow either XLR or TRS plugs to be
used. With XLRs the input impedance is 2400 ohms which is suitable for mics but may be low for
some line level gear, especially semi-pro and consumer gear. The symptom would usually be
premature clipping. If one uses a 1/4" TRS plugs, then the input impedance switches to 82K ohms
which is an easy load for almost all gear including guitars and basses but probably too high for many
mics. In other words use XLR plugs with mics and TRS with instruments and either with pro line
level sources and it automatically works. With semi pro -10 dBv gear and synths, you will usually
get best performance with TRS plugs and turning the MIC GAIN up 1 notch to "15 dB" of gain.
PIN 1 = SLEEVE = GROUND = SHIELD
PIN 2 = TIP = HOT = Positive
PIN 3 = RING = LOW = Negative
These inputs allow inputs as hot as +30 dBu balanced or +24 dBu unbalanced before clipping when
the MIC GAIN is set for "0 dB", which is about 6 dB better than most pro gear can send, so clipping
the mic inputs with line signals should be unusual. The LINE INPUT channels use this same 0 dB
configuration. The MIC INPUTS also allow for 60 dB of maximum gain with the MIC GAIN turned
up sufficient for most miking situations with another 10 dB with the MIX levels cranked.

11) INSERT JACKS. These TRS jacks allow the amplified mic signals to be sent and returned from
a compressor, EQ, gate, etc. A front panel switch (INS) is used to turn on a relay to use the return or
to bypass the rack processing and extra components in the signal path. This insert is post mic pre, but
before the MIX gain, MUTE and PAN.
T= TIP = SEND, R= RING = RETURN, S = SLEEVE = Shield = Chassis Ground.
All signals are unbalanced and follow a standard wiring format used in many other mixers. There is
no point in providing and INSERT for the unity gain LINE INPUTS because we can patch an EQ or
other device between the source and mixer and retain balancing and headroom and avoid unneeded
extra components in the path but because Mic Preamps provide needed gain there is a definite need
for INSERTS there.

12) CHANNEL OUTPUTS. Balanced outputs used to feed individual tracks on a multitrack recorder
or A to D converter. These outputs are after the MIX GAIN controls but are not muted by the MUTE
button. So by muting, you can eliminate these channels from the mix buss but still send to a
recorder. This way, you can use the Mic Pre, Phase Switch, Insert and Mix Gain (for fine level
control) on its way to a multi-track. These outputs are capable of +30 dBm drive levels once again
enough to pin the meters of most anything.
T= TIP = HOT = +, R = RING = Low = -, S = SLEEVE = Shield = Chassis Ground.

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13) TAPE PLAYBACK INPUTS. Used for returning a 2 track tape machine or DAT back to the
mixer for monitoring, checking or just listening. Once one records a mix, it is always a good idea to
check playback. The 5 position monitor select switch on the front hast to be in the "TAPE" position
to hear the playback. These are balanced inputs, TIP hot.

14) EXT INPUTS. Used for chaining mixers for 32 channels if you have 2 mixers and the 1/4" MIX
outputs are fed from the other mixer into these jacks. On MIC VERSION mixers there is a gain
control on the front panel (EXT) and on LINE VERSION it is a unity gain input direct into the mix.
These inputs can be used as an effects return if not required for chaining mixers. These are balanced
jacks, TIP hot, RING neg.

15) AUX OUTPUT. Only on the LINE and 8+8 VERSIONS. This is the effect send or a mono
headphone send. Channels can feed this jack if their AUX control is turned up and the AUX knob in
the master section is also up. This is an unbalanced output on a balanced TRS jack and can be used
to feed balanced or unbalanced inputs.

16) SOLO LINK. If one has 2 mixers, they can simply connect a wire between these terminals to
link the SOLO system. This allows you to solo one channel and the other 31 channels mute. If the
16x2 is used as a "sidecar" for a large console, it might also be used to link to the solo system of the
larger desk. 12 volts = no solo, 0 volts = solo. This is a mini banana post and not the larger size used
on test gear.

17) GROUND POSTS. Generally, there should be a wire connecting these two posts. One is
CHASSIS GROUND which is also the third pin of the AC plug. The other post is AUDIO
GROUND which is the zero volt common of all the audio signals. Having these grounds accessible
is useful for solving hum problems and for installations with custom ground schemes. For reference,
all 1/4" TRS sleeves or shield points are taken to chassis ground, and all rings are taken to audio
ground via a 30 ohm resistor. The internal star ground reference is on the left tube board at the
summing transformers / power connector.

18) LINE INPUTS. These are COMBI jacks that allow either XLR or TRS plugs to be used. Unlike
the MIC INPUTS the input impedance is always 82K ohms which is an easy load for almost all gear
including guitars and basses. With semi pro -10 dBv gear and synths, if more gain is needed, a
resistor can be added on any channel to increase gain as required. See page XX for details.
PIN 1 = SLEEVE = GROUND = SHIELD
PIN 2 = TIP = HOT = Positive
PIN 3 = RING = LOW = Negative
These inputs allow inputs as hot as +30 dBu balanced or +24 dBu unbalanced before clipping which
is about 6 dB better than most pro gear can send.

19) CHANNEL OUTPUTS. Balanced outputs used to feed individual tracks on a multitrack recorder
or A to D converter. These outputs are after the MIX GAIN controls but are not muted by the MUTE
button. So by muting, you can eliminate these channels from the mix buss but still send to a recorder
with these jacks. This way, you can use the Mic Pre, Phase Switch, Insert and Mix Gain (for fine
level control) on its way to a multi-track. These outputs are capable of +30 dBm drive levels once
again enough to pin the meters of most anything.
T= TIP = HOT = +, R = RING = Low = -, S = SLEEVE = Shield = Chassis Ground.

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