Mesa/Boogie V-TWIN User manual

Owner's Manual
OOGIE
B
MESA
1317 Ross Street Petaluma, CA 94954
USA
The Spirit of Art in Technology
PAGE SIZE 7 wide X 9 1/2high

Hello from the Tone Farm...
..You, smart player and all around intuitive human, have put your
trust in us to be your amplifier company. This is something we do not
take lightly. Our reward is that we've made a classic pre-amplifier and
by choosing this wonderful unit, you have become part of the MESA
family...WELCOME! Our goal is to never let you down. Your reward
is that you are now the owner of an archetypal guitar pre-amp, bred of
fine all tube amp heritage...benefiting from the many pioneering and
patented MESA circuits that led to the refinement of your new
instrument. Feel confident, as we do, this amp will inspire many hours
of musical satisfaction and lasting enjoyment. It was built with you in
mind, by players who know the value of a fine musical instrument and
the commitment it takes to make great music. The same commitment to
quality, value and support we make to you...our new friend.

PRECAUTIONSPRECAUTIONS
ALL OF THE OUTPUTS WHEN CONNECTED TO THEIR RESPECTIVE
SOURCES ARE CAPABLE OF PRODUCING VERY LOUD SOUND
LEVELS AND EXPOSURE TO THESE HIGH VOLUMES MAY CAUSE
THE USER PERMANENT HEARING DAMAGE.
No user serviceable parts inside. Refer service to qualified personnel. Always unplug
AC power before removing chassis.
READ AND FOLLOW INSTRUCTIONS OF PROPER USAGE.
Your MESA/Boogie Amplifier is a professional instrument.
Please treat it with respect and operate it properly.
USE COMMON SENSE AND ALWAYS OBSERVE THESE PRECAUTIONS:
Do not expose amplifier to moisture, rain or water, direct sunlight
or extremely high temperatures.
Always insure that amplifier is properly grounded.
Always unplug AC power cord before changing tubes.
Avoid direct contact with heated tubes.
Insure adequate air circulation around this pre-amp.
Keep amplifier away from children.
Do not throw or drop amplifier, especially on living beings.
Be sure to connect to an AC power supply that meets the power
supply specifications listed on the rear of the unit.
If there is any danger of lightning occurring nearby, remove the
power plug from the wall socket in advance.
To avoid damaging your speakers and other playback equipment,
turn off the power of all related equipment before making the
connections.
Do not use excessive force in handling control buttons, switches
and controls.
Remove the power plug from the AC mains socket if the unit is to
be stored for an extended period of time.
Do not use solvents such as benzene or paint thinner to clean the
unit. Wipe off the exterior with soft cloth.
Be sure to have the warranty card for this product filled out by the
store at which it was purchased and return to MESA Engineering.

PRECAUTIONSPRECAUTIONS
Congratulations on your purchase of the V-TWIN! This handbuilt, all tube, 3 mode pre-
amp combines all the features and versatility found in our trademark pre-amplifiers and offers them up in a
compact and rugged floor format. Historically, floor pre-amplifiers have been used primarily to add or
enhance gain and flexibility to existing stand alone combos or heads. V-TWIN does this extremely well,
offering three sounds, two of them footswitchable and can create tone that will surely rival, if not shame all
but the most diligently tweaked contenders. However, V-TWIN does not stop here! A full blown pre-amp, V-
TWIN goes on to become an ingenious and innovative brain to any rack system by providing an optimized
output for interfacing with power amps. To complete its arsenal, V-TWIN packs a high caliber recording
circuit that appears in the form of the Mixer/Headphone jack. This studio helper makes direct to tape
recording a breeze, minimizing set up time and the many hours normally spent on microphone placement
and cabinet swaps.
And finally, the best feature of all...the V-TWIN will fit into just about any standard size gig or accesory bag
that you would normally store your cords and other related tools of the trade in. This compact format allows
you amazing tone wherever you may roam. The ultimate spare rig, sit - in - savior or personal headphone
stack...V-TWIN provides many possible ways to enjoy your playing a whole lot more!
V TWIN
Connect the desired output to its intended source using shielded
cable of the shortest convenient length available. The three choices are:
CHOOSING A SOURCE OUTPUT:
MIXER /
INPUT
FOOT
SWITCH
VOLUME MASTER LEAD MASTER TREBLE BASS MIDDLE REVERB PRESENCE STUDIO 22+
STANDBY
ON
POWER
ON
HEADPHONES TO POWER
AMP TO GUITAR
AMP
MIXER
123456
PAGE 1
Connect the 12 volt power supply adapter to the jack located in the center on the rear panel
of unit.
POWER UP:
12VAC - 1 AMP
50 / 60 Hz
POWER SUPPLY
AC - 1 ONLY
HANDBUILT IN PETALUMA, CA, USA
OOGIE
B
MESA
EXTERNAL
SELECT EXTERNAL
BYPASS INSTRUMENT
INPUT
TO POWER
AMP TO GUITAR AMP
MIXER /
HEADPHONES
STEREO SIMUL CLASS 2: NINETY
LEVEL A LEVEL B
MESA
MESA

BASIC SET-UP:
Set the controls as per this diagram. Then run through the 3 sounds by using the
Channel Select footswitch and the Alternate Channel push key located between the Middle and Treble
controls.
GAIN BASS MIDDLE TREBLE PRESENCE MASTER
ALTERNATE CHANNEL
BLUES
CLEAN SOLO
BYPASS
BYPASS CHANNEL
However, the Normal configuration works great if you need an alternate clean sound of a different level and
tone. The Normal position can also work great for driving an amplifier's front end stage into clip by using the
Clean mode and setting V-TWIN'S Gain control high and switching it in for the pushed rhythm sound or a
lower gain Solo sound.
GAIN BASS MIDDLE TREBLE PRESENCE MASTER
ALTERNATE CHANNEL
BLUES
CLEAN SOLO
BYPASS
BYPASS CHANNEL
LED BYPASS
LIGHT ON
USE TO SELECT THE
BYPASS MODE... USE TO SELECT THE
BLUES / SOLO MODES
LED WILL LIGHT
BLUE OR RED
INPUT
FOOT
SWITCH
VOLUME MASTER LEAD MASTER TREBLE BASS MIDDLE REVERB PRESENCE STUDIO 22+
STANDBY
ON
POWER
ON
JACK
LOCATED ON
BACK PANEL
OF V-TWIN
TO GUITAR
AMP
This jack is provided to allow interfacing with existing amplifiers, giving the user an
additional three sounds (two are footswitchable) and thus
expanding the potential of virtually any amp. You will find the
inherent quality of V-TWIN'S voices to be a nice addition to even
the coolest circuits. When using this jack the V-TWIN can be set
up two different ways: Normal = Footswitchable from Clean
to Solo, or Alternate = Footswitchable from Blues to Solo.
In most situations using an existing amplifier that has a clean
channel - one would choose the Alternate configuration.
In this set-up you would use the host amplifier's clean sound
having V-TWIN in Bypass (LED on) and activate V-TWIN for two
different soloing sounds...Blues or Solo. See illustration below.
1
TO GUITAR AMP:
2
AND USE THE HOST AMPS
CLEAN SOUND.
()
PAGE 2
OUTPUTS:
MESA

TO POWER AMP:
This jack provides a hotter signal level and a slightly different E.Q. curve for
interfacing with the FX Return stage of any amplifier, or
simply to use V-TWIN as a stand alone pre-amp with an
existing power amplifier. (We suggest an all tube power
amp...e.g. MESA'S Stereo Simul-Class 2 : Ninety or
Fifty / Fifty.)
The level here should be more than enough to drive even
much less sensitive Non-MESA amplifiers.
JACK
LOCATED ON
BACK PANEL
OF V-TWIN
TO POWER
AMP
MIXER / HEADPHONES:
TO MIXER /
HEADPHONES
JACK
LOCATED ON
BACK PANEL
This 1/4" output and its accompanying switch ( located on the side panel )
support V-TWIN's recording circuit. This circuit is voiced to re-create the
sounds you're accustomed to hearing from the "To Guitar Amp" and "To
Power Amp" outputs. With the Record circuit mode switch
set to "MIXER," the output level is optimized for console
input stages (with all controls set at 12' o clock = +10 db.)
This should be more than adequate for most all direct
applications, allowing adjustment in either direction. Use
the Master control to vary the level at this output.
MIXER
CH3 CH4 CH5 CH6 CH7 CH8
When the rocker switch is set to "Headphones," the output level remains constant, but the tip is connected
to ring internally on the jack making stereo phoning possible. Use the Master to adjust the listening level.
Keep in mind the type and quality of headphones greatly affect the performance of this circuit, with the fully
enclosed, studio quality type producing the best results.
V-TWIN can be controlled by an external switching source to select between
two of the three modes. This can be most any tip to ground type switch logic. This feature makes possible
the inclusion of V-TWIN into programmable rigs or multiple pre-amp rigs where the units within are
controlled by a programmable switcher.
NOTE: V-TWIN must remain in the power-up switch logic to be controlled via this jack. In other
words...every time you get ready to use the unit in an External Select situation, remove the A.C. adaptor and
plug it back in without choosing any modes...Leave it alone. This procedure clears the switching logic
leaving the circuit in the receive-ready state and awaiting commands from the external switching device.
EXTERNAL SELECT:
The Bypass function may also be triggered by an external switching device.
This logic is controlled via a standard tip to ground type switch. This jack performs the same function as the
footswitch located on the face of the unit. It is wise to use the same power-up procedure as when using the
External Select to clear the switching logic.
EXTERNAL BYPASS:
PAGE 3
When the Bypass Footswitch is selected (and
the LED goes out,) all sound is muted at this output.
NOTE:
CONTROL JACKS:
STEREO SIMUL CLASS 2: NINETY
LEVEL A LEVEL B
MESA

Now that you have a better understanding of the Outputs and set-up procedures,
let's listen to a few sample settings...Keep in mind that if you are using the TO GUITAR AMP jack, the
setting of the host amp determines much of the overall character of the sound. We suggest you start by
plugging into the host amplifier first and dialing up a balanced and warm clean rhythm sound. Watch out for
excessive highs or lows, as an over abundance of either of these frequencies can make it difficult to create
a great lead sound.
SPARKLING CLEAN: CLEAN MODE:
Neck Single / All 3 Singles
GAIN BASS MIDDLE TREBLE PRESENCE MASTER
1
(continued on page 5)
PAGE 4
SAMPLE SETTINGS:
PUSHED RHYTHM / BLUES SOLO: CLEAN MODE:
Neck Single
GAIN BASS MIDDLE TREBLE PRESENCE MASTER
2
PURRING BLUES : BLUES MODE:
Neck Single
3GAIN BASS MIDDLE TREBLE PRESENCE MASTER
HINT: It is possible to alter the gain structure of all three modes in V-TWIN by simply replacing
one or both 12AX7 tubes housed under the shielding cage with 12AT7 tubes. This will reduce the
amount of gain fairly substantially without compromising the V-TWIN's overall voice. Make sure the
unit has not been in use just prior to this simple user mod as hot pre-amp tubes can cause severe
burns.
SUGGESTED SAMPLE SETTINGS

PAGE 5
(continued)
SAMPLE SETTINGS:
These settings are mere suggestions that should get you in theball park so to speak...taking into
account pick-up differences and host amp / power amplifier variables. Spend time with the controls as they
interact with each other a great deal and sometimes the frequencies you wish to adjust lie in more than one
control i.e. to adjust high "cut" work with upper regions of the Mid control, as well as the Treble and
Presence controls. To soften the sound reduce Mid while increasing Bass. With some time well spent,
you'll find so many great sounds...you'll think V-TWIN was and is, the deal of the century.
HINTS
JUICY HIGH GAIN LEAD: SOLO MODE:
Bridge Humbucking
GAIN BASS MIDDLE TREBLE PRESENCE MASTER
6
STINGING BLUES: BLUES MODE:
Neck or Bridge Single
GAIN BASS MIDDLE TREBLE PRESENCE MASTER
4
CRUNCH RHYTHM: SOLO MODE:
Bridge Humbucking
GAIN BASS MIDDLE TREBLE PRESENCE MASTER
5

GAIN BASS MIDDLE TREBLE PRESENCE MASTER
ALTERNATE CHANNEL
BLUES
CLEAN SOLO
BYPASS
BYPASS CHANNEL
MIXER /
HEADPHONES TO POWER
AMP EXTERNAL
SELECT EXTERNAL
BYPASS
12VAC - 1 AMP
50 / 60 Hz
POWER SUPPLY
AC - 1 ONLY
TO GUITAR
AMP INSTRUMENT
INPUT
MESA OOGIE
BR
HAND BUILT IN PETALUMA, CA, USA
V-TWIN Rear View
V-TWIN Front View
JACKS pt# (all)
JACKS pt# (all) JACK pt#
POT pt# POT pt# POT pt# POT pt# POT pt# POT pt# KNOBS pt# (all)
LED LIGHT (red) pt#
LED LIGHT (blue) pt#
SWITCH pt# SWITCH pt#
THUMB SCREW L & R pt#
MIXER PHONES
NOTE: This switch is located on the right side of the unit pt#
R
L
612391
618112
JACK pt#
612712 618112
601901
408110
395439
395753
LED HOLDER pt# (all) 395755
600400
600400
LED LIGHT (green) pt#
LED LIGHT (red) pt#
395438
395753
CAP pt#
SHAFT pt#
PLUNGER pt#
600203 600201 600202
302063
594737 594739 594737 594149 594739 594378

Thank you for trusting MESA/Boogie to be your amplifier
company. We wish you many years of toneful enjoyment from this
handbuilt all tube instrument.
The Spirit of Art in Technology
OOGIE
B
MESA