Manley STEREO VARIABLE MU operation manual

MANLEY

OWNERʼS MANUAL

THE MANLEY

LIMITER / COMPRESSOR

STEREO VARIABLE MU

®

13880 Magnolia Ave.
Chino, California 91710
www.manleylabs.com

[e-mail]

Tel: [phone]

Fax: [phone]

LABORATORIES, INC.

MANLEY

STEREO VARIABLE MU®

LIMITER COMPRESSOR

OWNER’S MANUAL

TUBES

brought to you by the clever folks at:

MANLEY LABORATORIES, INC.

RULE

13880 MAGNOLIA AVE.

CHINO, CA. 91710 USA

TEL: [phone]
FAX: [phone]

email: [e-mail]

website: www.manley.com

CONTENTS

SECTION PAGE

INTRODUCTION 3

MAINS CONNECTIONS 4

INSTALLATION 5

FRONT PANEL 6

REAR PANEL 7

EXAMPLE SETTINGS 8

FRONT PANEL ADJUSTMENTS 9

OPERATIONAL NOTES 10

MASTERING AND M/S MODELS 11

T-BAR MODIFICATION 12

GAIN REDUCTION CURVES 13

SPECIFICATIONS 14

TECHNICAL NOTES 15

SERVICE ADJUSTMENTS 16

BLANK TEMPLATE TO STORE SETTINGS 17

CDrev5.11.11

INTRODUCTION

THANK YOU!...

for choosing the Manley Laboratories Stereo Variable Mu
been our best selling product for many years. It is one of the very few compressors that has be­come a real standard in Mastering studios and contributed to most hit records over the last decade
and probably the next. “Mu” is tube-speak for gain, and Variable Mu® is our registered trademark
for this limiter compressor. It works by using the “remote cut-off” or re-biasing of a vacuum tube
to achieve compression. The precious vintage Fairchild 670 also uses this technique and is one

of few all-tube compressor to do so, that we know of. Even the side-chain has glowing rectier

bottles. How’s it work? The unique 5670 dual triode is at the center of the peak-reducing and

compression action constantly being re-biased by the vacuum tube rectied side-chain control

voltages which cause this tube to smoothly change its gain. Just like that.

LOCATION & VENTILATION

The Manley Stereo Variable Mu

®

Limiter Compressor must 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 and bottom of the unit such that constant movement of air can

ow through the ventilation holes. There are 8 tubes inside this unit so it does run quite hot.
Good ventilation is denitely encouraged.

UNPACKING: Unpack the unit carefully by removing all the custom foam packing material
and make sure that all supplied accessories are present. Carefully examine all items for any pos­sibility of shipping damage. All of the tubes are already installed and should have survived the
journey from our factory to your studio. They should be standing at attention in their sockets,
and should show no signs of distress such as chipped glass, loose internal components or obvi­ous breakage. If the unit is damaged or fails to operate, notify the shipper or your dealer or us or
your local authorities immediately. Or if you suspect The Shipping People threw it off the air­plane and onto your front porch whilst ying overhead at 30,000 feet, notify the shipping com­pany without delay and complain to them as we only guarantee this unit to be able to survive a
drop of 23,487 feet or less.

®

Limiter Compressor. this unit has

Your Manley Variable Mu

®

Limiter Compressor was packed with extreme love and care, and

each box includes the following components and accessories:
a) 1 each, 6 foot IEC 3-conductor power cable

b) 1 each, Owner’s Manual (that we hope you will keep reading.)

It is prudent to retain the shipping materials for future use, as they are custom-formed for this
unit and will greatly minimize the chance of shipping-related damage should you ever need to put
your precious Variable Mu

®

in the careless hands of The Shipping People again. We have heard
that certain rodents might enjoy munching on the packing foam. We are sorry to report that we do
not warranty the packing foam against attack by mice, rats, or other hungry critters, hungry chil­dren, hungry neighbors, etc. Try glue traps or spring-traps loaded with peanut butter to eliminate
these unwelcome freeloaders from your property.

3

MAINS CONNECTIONS

Your VARIABLE MU has been factory set to the correct mains voltage for your country. The voltage setting is

marked on the serial badge, located on the rear panel. Check that this complies with your local supply.

 Exportunitsforcertainmarketshaveamouldedmainsplugttedtocomplywithlocalrequirements.Ifyourunit
doesnothaveaplugttedthecolouredwiresshouldbeconnectedtotheappropriateplugterminalsinaccordance

with the following code:

GREEN/YELLOW EARTH
BLUE NEUTRAL
BROWN LIVE

As the colours of the wires in the mains lead may not correspond with the coloured marking identifying the termi­nals in your plug proceed as follows:

The wire which is coloured GREEN/YELLOW must be connected to the terminal in the plug which is
marked by the letter E or by the safety earth symbol or coloured GREEN or GREEN and YELLOW.

The wire which is coloured BLUE must be connected to the terminal in the plug which is marked by the letter
N or coloured BLACK.

The wire which is coloured BROWN must be connected to the terminal in the plug which is marked by the
letter L or coloured RED.

DO NOT CONNECT/SWITCH ON THE MAINS SUPPLY UNTIL ALL OTHER CONNECTIONS HAVE
BEEN MADE.

Waste Electrical and Electronic Equipment (WEEE)

Information for customers:

TheEuropeanParliamentandtheCounciloftheEuropeanUnionhaveissuedtheWasteElectricalandElectronicEquipmentDirective.ThepurposeoftheDirec­tiveisthepreventionofwasteofelectricalandelectronicequipment,andtopromotethereuseandrecyclingandotherformsofrecoveryofsuchwaste.Assuch

the Directive concerns producers, distributors and consumers.

TheWEEEdirectiverequiresthatbothmanufacturersandend-consumersdisposeofelectricalandelectronicequipmentandpartsinanenvironmentallysafeman­ner,andthatequipmentandwastearereusedorrecoveredfortheirmaterialsorenergy.Electricalandelectronicequipmentandpartsmustnotbedisposedofwith
normalhouseholdwastage;allelectricalandelectronicequipmentandpartsmustbecollectedanddisposedofseparately.

Productsandequipmentwhichmustbecollectedforreuse,recyclingandotherformsofrecoveryaremarkedwiththefollowingpictogram:

Smallproductsmaynotalwaysbemarkedwiththispictograminwhichcasethisispresentintheinstructionsforuse,ontheguaranteecerticateandprintedon

the packaging.

Whendisposingofelectricalandelectronicequipmentbyuseofthecollectionsystemsavailableinyourcountry,youprotecttheenvironment,humanhealthand
contributetotheprudentandrationaluseofnaturalresources.Collectingelectricalandelectronicequipmentandwastepreventsthepotentialcontaminationof

naturewiththehazardoussubstanceswhichmaybepresentinelectricalandelectronicproductsandequipment.

Your MANLEY or LANGEVIN retailer will assist with and advise you of the correct way of disposal in your country.

4

INSTALLATION

Please refer to the REAR PANEL section for a full layout of the rear panel of your Man­ley Stereo Variable Mu

1. Make sure your mains voltage supply agrees with the voltage this unit is set for.

2. Be certain that the unit has the proper fuse installed.

3. Connect the input signal(s) to the 3 pin female XLR’s on the rear panel. The
input XLR’s are TRANSFORMER COUPLED balanced wired as follows:

PIN 1: GROUND
PIN 2: (+) POSITIVE GOING PHASE
PIN 3: ( - ) NEGATIVE GOING PHASE

4. Connect a 3 pin XLR cable to the male output XLR on the rear panel. The out­put XLR is balanced and the pinout is wired as follows:

PIN 1: GROUND
PIN 2: (+) POSITIVE GOING PHASE
PIN 3: ( - ) NEGATIVE GOING PHASE

The output impedance is 600 Ohms nominal.

®

Limiter Compressor.

5. Connect a standard IEC mains cable to the IEC mains socket on the rear panel.

6. Check that the power is switched off on the unit.

7. Connect the IEC mains cable to a 50/60 Hz AC source of the proper selected volt­age.

8. Power up the unit and allow it enough time to stabilize before using . it takes about
30 minutes for everything to stabilize and for it to warm up and sound its best.

Again, let us remind you: this unit runs pretty hot. We denitely encourage allowing

enough space around the chassis so that convection of air can occur and heat can be drawn
away from the unit. If the heat gets all trapped with no place to go, you’ll just bake up the
guts of the unit faster and you’ll be in for a re-cap years sooner than if you had some ventila­tion happening. Try to give the Variable Mu

®

at least an inch or two on top so that air can

ow up and away from it.

If you wish to keep pizzas warm on top of the Manley Variable Mu

®

, please use a plate
so the cheese does not drip down through the top cover holes into the unit. Your Warranty
does not cover damage arising from foreign (or domestic) dairy substances entering the unit.

5

FRONT PANEL

C

E

A H B D F

A IN / BYPASS Switched in bypass mode, (down position) all effects of the limiting circuitry are

B. COMP / LIMIT Selects compression ( 1.5:1) or limiting (4:1) function. Compression is soft -knee,

C. RECOVERY Recovery times can be selected between

bypassed and will not affect the audio signal. In the bypass mode , the audio
signal passes from the input directly to the output (hardwire).

Limit is a sharper knee. At greater than 12dB of limiting the ratio increases (up to
20:1 maximum)

a. VERY SLOW 8 seconds
b. SLOW 4 seconds
c. MEDIUM 0.6 seconds
d. FAST 0.4 second

e. VERY FAST 0.2 second

G E

I

J J

C

F

D B H A

D. THRESHOLD Continuously variable gain reduction threshold control.

Determines the necessary amplitude for compression or limiting to take effect.
Most extreme effect is at the MIN (fully counter clockwise) position. The lower
the threshold, the more that gets limited.

E. OUTPUT ATTENUATE Continuously variable attenuation of output signal leaving the amplier circuitry.

Full attenuation occurs at the full counterclockwise position.
This control is active only in IN mode.

F. ATTACK Continuously variable sensitivity of transient detection. Determines the neces-

G. DUAL INPUT Continuously variable attenuation of input signal entering the amplier limiting

trol is active only in IN mode.

H. GR METER Measures (in decibels) amount of reduction.

I. LINK When switched to “SEP” left side is independent from the right side. When

switched to “LINK” both channels are reduced in gain by the same number of dB.
This insures that the stereo image is unchanged. The METERs remain independent
to help set THRESHOLDs.

POWER ON/OFF Power is supplied to the unit when switched UP. Meters will illuminate.

J. HP SC IN / OUT When switched to “IN”, the side chain will not respond as strongly to low

frequency content. These switches can be used with bass-heavy music where

you don’t want the bass driving the WHOLE action of the compressor. The lter
is a very gentle 6dB/octave 1-pole lter, and will typically be down 1-3dB at

100Hz and down 4-6dB at 50Hz. As you decrease the frequency, the amount of
limiting will also decrease.

sary length of transient to initiate gain reduction. Fast =25mS, Med =50mS, Slow
=70mS. Fully counter clockwise at the slowest setting will prevent most percus­sive signals from causing limiting or compression.

circuitry. Full attenuation occurs at the fully counterclockwise position. This con-

6