Mesa/Boogie Three Channel Dual & Triple Rectifier Solo... User manual

OOGIE
B
MESA
SOLO HEADS
Owner's Manual
DUAL & TRIPLE

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. By purchasing and
choosing this unit to be a part of your musical voice, 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 a great 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.

Precautions
OVERVIEW & INSTANT GRATIFICATION 1
FRONT PANEL CONTROLS
POWER-UP 2
GAIN / TREBLE / MIDDLE 3/4
BASS / PRESENCE 5
MASTER and LOOPACTIVE MASTER 6
TOGGLE SWITCHES:
POWER / ON and ON / STANDBY 7
REAR PANEL CONTROLS, SWITCHES & JACKS
OVERVIEW 8
FUSE 8
RECTIFIER SELECT 8/9
BIAS SWITCH 9
FX - Send & Return 9
SEND LEVEL CONTROL 10
LOOP SELECT ROTARY CONTROL 10
SLAVE LEVEL CONTROL 10
SPEAKERS 10/11
EXTERNAL SWITCH JACKS 11
CHANNEL STYLE SELECT 11
CHANNEL SELECT 11
FACTORY SAMPLE SETTINGS 12
PERSONAL SETTINGS SHEET 13
TUBE DESCRIPTION & TASK CHARTS 14/15
TUBE NOISE & MICROPHONICS 16
DIAGNOSING PRE-AMP TUBE PROBLEMS 17
BIASADJUSTMENT: Afeature article by Randall Smith 18/20
SPEAKER IMPEDANCE 7 POSSIBLE HOOK-UP SCHEMES -Amplifier to Speaker Cabs 21/26
TRIODES, PENTODES & IRISHMEN: Afeature article on the workings of tubes 27/29
PART SHEETS 30/31
DUAL & TRIPLE RECTIFIER
TABLE OF CONTENTS
SOLO HEADS

PRECAUTIONS & WARNINGS
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:
YOUR AMPLIFIER IS LOUD! EXPOSURE TO HIGH SOUND VOLUMES MAY CAUSE PERMANENT HEARING DAMAGE !
No user serviceable parts inside. Refer service to qualified personnel. Always unplug AC power before removing chassis.
EXPORT MODELS: Always insure that unit is wired for proper voltage. Make certain grounding conforms with local standards.
READ AND FOLLOW INSTRUCTIONS OF PROPER USAGE.
WARNING: EU: permission from the Supply Authority is needed before connection.
WARNING: Vacuum tube amplifiers generate heat. To insure proper ventilation always make
certain there is at least four inches (100mm) of space behind the rear of the amplifier cabinet.
Keep away from curtains or any flammable objects.
WARNING: Do not block any ventilation openings on the rear or top of the amplifier. Do not
impede ventilation by placing objects on top of the amplifier which extend past the rear edge of
its cabinet.
WARNING: Do not expose the amplifier to rain, moisture, dripping or splashing water. Do not
place objects filled with liquids on or nearby the amplifier.
WARNING: Always make certain proper load is connected before operating the amplifier.
Failure to do so could pose a shock hazard and may result in damage to the amplifier.
Do not expose amplifier to direct sunlight or extremely high temperatures.
Always insure that amplifier is properly grounded.Always unplugAC power cord before
changing fuse or any tubes. When replacing fuse, use only same type and rating.
Avoid direct contact with heated tubes. Keep amplifier away from children.
Be sure to connect to anAC power supply that meets the power supply specifications listed on
the rear of the unit. Remove the power plug from theAC mains socket if the unit is to be stored
for an extended period of time. 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. 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 filled out by the store at which it was purchased and return to
Mesa/Boogie.

Congratulations for choosing either the DUAL or TRIPLE RECTIFIER Solo Head. You have purchased a handbuilt instrument
of the finest quality and craftsmanship. A unique blend of yesteryear’s black magic power section design combined with our race-
shop approach to finely tuned, high gain pre-amp circuitry leaves both of these amps standing alone...instantly classics and destined
for vintage status. With two channels housing three definitive and distinctly different Modes, a complete array of supremely dialed
guitar sounds can be obtained quickly and easily. Add to this Patented Switchable Rectifiers (Tube/Silicon Diode,) and Channel
Style Select, a hard Bypassable / Channel Assignable FX Loop, Spongy / Bold AC. Power, Reverb and you’ve got the most performance
packed, bodacious self contained guitar amp ever. And if all these features don’t tell the truth about the DUAL or TRIPLE
RECTIFIER Solo Head...how about the on board Bias switch that enables you to use either 6L6 or EL34 power tubes. Customize
this dynamic power section for the tube style that fits your music best!
Looking to the Rear Panel assures that all your interfacing needs are covered. A Parallel Effects Loop with a Mix control provides
tone insurance for even those questionable effects. To use either of these two RECTIFIER Solo Heads in larger rack systems, or
to interface to other power sections, the Slave Jack and Level control is a welcome feature. Three speaker jack combinations have
been provided...two 4 Ohm, one 8 Ohm and one 16 Ohm - to ensure the proper impedance match to many types of speaker
enclosures. The other features will prove to be quite valuable to you and further along in this manual they are covered extensively.
Below are illustrations of the TRIPLE RECTIFIER Solo Head - the DUAL RECTIFIER Solo Head has the identical Front and
Rear Panel layout and features. Therefore, we will be using the illustration of the TRIPLE RECTIFIER Solo Head throughout this
owner’s manual in regards to identifying and explaining the various on board features and controls.
First familiarize yourself with the layout of the Front Panel and locate the Footswitch Input jack. This jack, when connected to your
footswitch will allow you to select either the Lead or Rhythm channel remotely. The Rear Panel Channel Select toggle must be in the
PAGE 1
INPUTFT.SW
POWER
ON
ON
STANDBY
MASTER GAIN TREBLEMIDPRESENCE BASS
LOOP
ACTIVE
MASTER
CLEAN
LOOP
SOLO HEAD
FRONT VIEW :
DUAL or TRIPLE RECTIFIER
Solo Head Instant Gratification Demo Settings
REAR VIEW :
DUAL or TRIPLE RECTIFIER
Solo Head
FUSE
IMPORTANT: First, set sounds with
Loop Bypassed. Then set Send,
Mix & Loop Active Master (front) to
50% for unity gain. Loop on, adjust
Send to match FX use Loop Master
as return level & live volume
control, set Mix for effect depth.
SPEAKERS
HAND BUILT IN PETALUMA CA.
16 OHM 8 OHM 4 OHM 4 OHM
EXTERNAL
SWITCHING
CHAN.
LOOP
ORANGE
SET TO ORANGE
WHEN USING
FOOTSWITCH OR
EXT. SWITCH
CHANNEL STYLE SELECT
ORANGE CHANNEL GAIN
CLEAN
VARIABLE
HIGH GAIN
RECTIFIER SELECT
4A SB
2A
BOLDSPONGY
POWER
RETURN
SEND
SEND LEVEL
BIAS SWITCH
6L6 EL-34
CAUTION
BIAS SETTING
MUST MATCH
TUBES IN USE
LOOP SELECT
EXT
SW
RED
AUTO
ORG
AUTO
LOOP ON
ORG & RED
BYPASS
LOOP
MIX LEVEL
100% 0%
VACUUM
TUBES
(NORMAL)
SILICON
DIODES
(HI POWER)
120 VOLTS
60 Hz
4 AMPS
SLAVE LEVEL
SLAVE OUT
NORMAL
ORIG TO
MODERN RED TO
VINTAGE
RED
CHANNEL
SELECT
Operating Instructions
DUAL & TRIPLE
RECTIFIER SOLO HEADS

UP position (Orange.) If you don’t have a footswitch available, the Channel Switch located on the Rear Panel ( far left end of panel
if facing front of amp ) will activate this switching procedure. Before we get intimate with each control, let’s audition the two channels
with a basic clean setting in the Vintage Orange ( Rhythm Channel ) and a fairly high gain overdriven sound in the Modern Red (
Lead Channel.)
POWER-UP:
First remove the protective covers from the tubes (plastic webbing) before connecting
the AC. cord to a power receptacle. Connect your favorite guitar to the instrument Input jack. Flip the POWER switch ON
while leaving the STANDBY switch set to STANDBY. (It is always a good idea to practice this start up procedure as at least 30
seconds of warm-up time lessens the shock on cold power tubes, thus prolonging their life substantially.) Next, using the example
below as a guide, set the controls as illustrated and flip the STANDBY switch to the ON position to listen to the two distinctly different
channels using either the footswitch or the Channel Select toggle switch as mentioned in the paragraph above.
The above settings are merely examples of the channels, Vintage Orange and Modern Red. These two channels are voiced very
differently when the Channel Cloning (TM) switch, located on the left side of the Rear Panel, ( when viewing from the rear ) is set to
NORMAL. The Modes are selected using the toggle switch located on the Rear Panel far left side. Orange is the softer, sweeter of
the two channels and houses two Modes of operation Clean and Vintage High Gain. The Modern Red channel boasts two Modes
also and these are labeled Blues and Modern High Gain.
NOTE: It is normal to hear a volume level difference when switching from Clean to Variable High Gain. This difference will get larger
as the MASTER Volume is increased and the amp is played loud.
Since all the Modes are extremely useful and versatile, they may all be considered as Variable High Gain Modes with Clean being
the obvious lower gain of the four. We encourage experimentation as the names we have given each of the Modes refers more to a
region of gain than to a stylistic boundary.
The DUAL and TRIPLE RECTIFIER Solo Heads are extremely versatile and the amazing sounds of even one of the Modes
many times left us with the desire to have two of the same channels. This would allow a player to have two of the same Modes with
just different settings. That way a player could use, say, the Orange ( Vintage High Gain ) for a crunch rhythm sound and switch to
virtually that same sound with maybe a touch less Treble or a pinch more Gain and a higher Master setting for soloing. Or, maybe
one might want to use the Clean Mode in the Orange channel, yet want the Variable High Gain Mode in the Orange channel for a
different type of blues solo sound. This type of wish listing the channel configuration eventually led to the concept of Channel
Cloning (TM.) Since the switch for this feature is located on the Rear Panel, we will review it later in the manual under Rear Panel.
Now that you’ve heard the either the DUAL or TRIPLE RECTIFIER Solo Heads two channels, let’s move on to understanding
the controls and their interactive roles in achieving the sounds that you want to hear.
PAGE 2
FRONT PANEL:
INPUTFT.SW
POWER
ON
ON
STANDBY
MASTER GAIN TREBLEMIDPRESENCE BASS
LOOP
ACTIVE
MASTER
CLEAN
LOOP
SOLO HEAD
FRONT PANELS ARE THE SAME FOR BOTH DUAL & TRIPLE RECTIFIER SOLO HEADS

GAIN:
Like most amplifiers, the GAIN Control in each channel determines it’s sensitivity and overall tonal characteristics. It
meters the amount of Gain (volume) that your guitar signal will produce. In both the DUAL and TRIPLE RECTIFIER Solo
Heads, we paid special attention to the amount and frequencies of Gain
present in each Mode, making sure the whole range of available Gain is
musically usable. We also worked diligently with our suppliers to develop
pots with tapers useful to players that require that touch sensitive relationship
of input signal level to Gain saturation. An essential ingredient to a great
amps expressive nature. To maximize your expression, spend time learning
the different regions of Gain in each Mode and tonal colors they enhance.
Almost more - or certainly equal to the tone controls, the GAIN Control
shapes your sound.
In most guitar amplifiers and especially in all-tube circuits, the GAIN Control
is the most powerful control in the preamp. It shapes the overall style and
character of the sound and is responsible for whether the sound is clean,
overdriven or anywhere in between. In your RECTO, the GAIN Control is
even more powerful. It not only determines the amount of drive, but also
acts as an integral part of the tone control string as well.
To simplify the GAIN Controls role in shaping the overall tone of the sound we will look at it in two ways - 1. alone and 2. in
conjunction with the tone controls.
1) By itself the GAIN Control has basically three tonal regions -
Low ( 7:00 - 11:00 ) provides the cleanest, least saturated sounds and in this region the sound will be brighter and contain more
upper harmonics lending a three dimensional character to the sound.
Middle ( 11:15 - 2:00 ) enhances the saturation and replaces some of the upper harmonics with a richer, warmer quality and a fuller
bottom end response. Not yet fully saturated, this region is the easiest place to get a great sound in both channels. This region
contains many of the RECTO’S best sounds...especially for soloing due to the crucial blend of an expressive attack combined with
ample sustain.
High ( 2:15 - 5:00 ) saturates the signal and enhances low and low mid frequencies. While this region provides the maximum
saturation and therefore sustain, if also compresses and softens the attack characteristics. For this reason we suggest using this
higher region of the GAIN Control sparingly and only when maximum sustain is needed.
NOTE: Due to the RECTO’S extreme gain potential, the highest regions of the GAIN Control may possibly push the pre-amp tubes
past what they can handle, producing microphonic squealing. While we screen and test the tubes your amplifier was shipped with
and the tubes in your amp passed our rigorous test, we can’t predict how the tubes will respond over time exposed to extreme gain
settings. Your tubes are warrantied for a period of 6 months under normal use, but you can save yourself the present and future
inconvenience of having to deal with annoying microphonic tube problems by simply using a little common sense...Don’t turn the
Gain all the way up!
If you must for a specific part of at very low volumes, back down the TREBLE and PRESENCE Controls. Your RECTO was designed
to provide amazing gain and tone at less than extreme settings removing the need for you to crank everything all the way up. If you
are not able to achieve the sound you want at sensible setting on any or all of the controls, your problem may lie elsewhere in the
signal chain, i.e. pick-ups, cabinetry, processing, etc. Keep in mind you can always call on one of our product specialists Monday
through Thursday and seek some advice should you find yourself struggling to get the sound you want.
PAGE 3
CONTROLS:
INPUTFT.SW
GAIN
Brightest Most Balanced
Warmer & Saturated
REGIONAL TITLES
ARE THE SAME FOR BOTH GAIN
CONTROLS

2.) GAIN - In conjunction with the Tone Controls -
Basically, a simple rule applies...as the Gain is increased the Tone control string has less and less effect on the signal until at 5:00
the signal is so saturated that you are getting mostly Gain and very little Tone. Again, this is the reason we suggest using the GAIN
Control in its middle region. Here the Tone control string is very active and provides maximum shaping power - allowing you to dial
virtually any sound you desire.
TREBLE :
As with most guitar amplifiers, the TREBLE Control in both channels of your RECTO is the most powerful of the
rotary controls and is next in line only to the GAIN Control as a shaping tool. Because it is first in the signal path of the tome controls
- and from here the MIDDLE and BASS receive their signal - it is by far the dominant tome control. For this reason the setting of the
TREBLE Control is very important for equal representation of the three frequency regions to appear at their respective controls.
Like most of the controls on your RECTO, there is an optimum region
of the TREBLE Control where ample top end is mixed in and yet
enough signal is still passed on to the MIDDLE and BASS Controls.
As you might surmise, here is the sweet spot. There are definitely
great sounds above and below this middle region ( 11:00 - 1:30 ), but
the balance between the TREBLE Control and the other tome controls
is compromised.
MIDDLE :
The MID Control determines the blend of midrange punch and boldness. It also has a great deal to do with how a
sound feels to play. Setting the Midrange low scoops the attack, making the sound and feel more liquid and resilient. Setting the MID
higher introduces more punch and authority, helping sounds cut through a mix better. Setting the Mids very high may make the
strings feel a little stiffer and less spongy. Keep this in mind when dialing up your sounds so that you can retain the best feel on the
strings, allowing you to always play your best.
At high Gain settings in either the Vintage Orange or Modern Red Modes,
the MID Control dials in punch and aggression. For the tightest crunch
chording, set the MID Control high, say around 12:00 - 1:30. To make
single notes feel juicier and more liquid, reduce the MID Control to around
7:30 or so. In the Modern Red Mode, using the MID higher and in
conjunction with the PRESENCE Control also set high, delivers a down right ugly crunch that’s huge and angry - not fit for the meek!
This setting also sounds great and becomes easier to play and more elastic feeling with the GAIN Control set at 1:00 or higher.
BASS:
This control blends in the lower frequencies and its effectiveness, again, depends on the setting of the TREBLE Control.
It should be set with moderation as extreme settings in either low or high directions can produce an unbalanced tone. Be especially
careful in higher Gain settings of either channel. Too much Bass will cause a
flabby unfocused sound. Try setting the BASS Control around 11:00 - 2:00 for
clean sounds in the Orange Channels Rhythm Mode. In the Vintage High
Gain Mode and the Modern Red channel, try setting the BASS control
somewhere between 11:00 - 2:00. These settings will vary with the amount of
Gain and Treble you have dialed up.
PAGE 4
The Controls: (Continued)
TREBLE
SWEET SPOT
INPUTFT.SW
GAIN
GAIN
INPUTFT.SW
TREBLE
MIDDLE
GAIN
INPUTFT.SW
TREBLE
MIDDLE
BASS

PRESENCE:
These are controls that work in the power section to reduce attack and brightness. They work on a different
frequency than the TREBLE Control, and depending on the Mode chosen, and the amount of Gain dialed up, can sound higher or
lower than the Treble frequency. In the Clean Mode it dials in sparkle and shimmer, letting clean sounds cut through better. Balance
the Treble and Presence until the desired blend is
reached. In distortion or high gain sounds in the
Orange Channels Variable High Gain Mode, you will
find it very helpful in darkening and compressing the
sound for single note work.
Set the Presence low and this compression will also
focus the notes and omit any unwanted buzzy
frequencies. For high gain chording try higher
settings of the PRESENCE Control to bring out the
harmonic haze.
In the Red Channel the Presence circuitry is quite
advanced because it switches from one type of Presence located in one part of the power section, to a different Presence circuit
located earlier in the pre-amp section. This switching makes the complete transformation possible and is responsible for achieving
the Modern High Gains absolute over the top status!
When the Modern High Gain Mode is called up, the Presence makes the move to a new place in the circuit and gets revoiced to work
on a lower frequency. Just right for adding attack and urgency, this Presence is the aggression control. It is normal for high settings
of this control to make Modern Red seem extremely loud in comparison to the other Modes. This is a result of unclamping what
worked as the Presence in the other two Modes and letting the DUAL or TRIPLE RECTIFIERS ponies run free.
It is in fact, the loudest setting on the amplifier. Use this Presence with discretion as it can make for some ear damaging, almost
harsh sounds if set too high. Try the Modern High Gain Mode with the GAIN Control set high, around to . Dip the MID Control to -
and then increase the PRESENCE Control to dial in the right attack and blend of aggression. You may want to play with the balance
between the MID and PRESENCE Controls as they are somewhat similar in that they are very powerful and dominant in Modern
Red. With these two controls dialed right, Modern Red is to this day the most huge and heinous crunch we’ve come across. When
you hear this, you will probably won’t believe that this could be the same amp that moments ago was crying the blues with such
mournful conviction.
Another cool use for this alternate Presence frequency shows up when you use the Vintage Orange Channels Clean Mode. Using
this example: Use the CHANNEL STYLE SELECT switch on the Rear Panel and revoice the Orange Channel to Modern. You will
hear your rhythm sound get louder and much punchier. This difference is largely
due to the moving and revoicing of the Presence.
This occurs automatically when you Modernize the Orange Channel and now
you instantly have a Vintage clean pre-amp with a Modern power section. This can be useful at larger gigs to boost the clean sound
volume level or simply as an alternate voicing of the same Mode style.
MOST BALANCED VOCAL QUALITY SAME FOR BOTH CONTROLS
INPUTFT.SW
GAINTREBLE
PRESENCE
PRESENCE BASS MID TREBLE GAIN
MASTER
The Controls: (Continued)
PAGE 5

MASTER:
A simple control found on most amps today, these serve to balance the playing level of the two channels. They
enable the pre-amps GAIN Control to be used in a wide range of settings, while never having to affect the listening level. On both the
DUAL and TRIPLE RECTIFIER Solo Heads these Masters serve another purpose as well. When the FX Loop is switched out
of Bypass and programmed to either channel specifically or, simply On all the
time, these MASTER Controls double as FX Loop Send Level Controls.
This is not their primary function, but the setting here does affect the channel’s
Send strength. This is not a problem because both the DUAL and TRIPLE
RECTIFIER’S Solo Heads loop also incorporates a Master Send Level Control
that compensates for the possible level mismatch when using the Masters to balance
the channels. We have found the middle ranges through to be very well behaved
for most effects. Setting the Masters in this region should make for trouble free FX
interfacing when using the loop.
LOOP ACTIVE MASTER:
This knob of a different color, works in conjunction with the FX Loop Select Rotary Control that is
found on the Rear Panel in the FX Loop section of the amplifier. When the Loop is switched out of Bypass the Yellow Loop LED
next to this control comes on with the channel in which the loop is active. When this LED is illuminated the Loop Active
Master replaces the Channel Masters to become the overall Master Volume Control. At this
time the Channel Masters become channel balancing controls and Effects Loop Send Level
Controls. This LOOP ACTIVE MASTER Control also serves as an effects Return Control and can
be very useful when trying to use certain older effects with weak output capabilities. It also makes it
much easier to use the Effects Loop and makes sure that no signal is being lost to an effect’s less
than adequate output circuit. Let’s try an experiment that will quickly show you why both the DUAL
and TRIPLE RECTIFIER’S Loop is the state of the art:
1.) Choose a sound in one of the channels and dial it in to your liking. 2.) Connect an effect
processor to the FX Loop Send and Return Jacks. 3.) Set the Effect’s input to preferably, but not
necessarily, to Line Level. 4.) Go to the Rear Panel of either the DUAL or TRIPLE RECTIFIER Solo Head and by using the
Rotary Loop Select Control, turn the Loop On all the time by setting this rotary to “Loop on Org. & Red”. At this time the Front
Panel Loop LED will come on notifying you that the LOOP ACTIVE MASTER now controls the Volume level of the whole amp. 5.)
Increase or decrease this to about the same playing level you had before turning the loop on. 6.) Now go to the other channel and
find a sound in one of the Modes.
7.) Use the Channel Master to determine its balance in relationship to the first channel you dialed up. When the listening levels are
satisfactory, double check your effects processor’s input headroom indicating LEDs or, if it is an old classic stomp box, listen for
unwanted clipping. 8.) Fine tune this Send Level strength with the Effects Send Level Control in the Effects Loop section found
on the Rear Panel. Use the Rotary Loop Select Control on the Rear Panel to toggle between Loop Bypass and 'FX On Org. &
Red.' 9.) Set the FX MIX Control to the desired 'wet' blend. 10.) Adjust the volume difference between these two positions with the
LOOP ACTIVE MASTER. If the processor you have used is a decent one, you should be able to compensate completely for any
tonal thievery the unit might have caused in amps with lesser loops.
When you toggle the Loop Select in this set up, you should hear the effect come on, without noticing a disappointing difference like
you would in many other effects patching scenarios. The LOOP ACTIVE MASTER helps greatly in avoiding this all too common
occurrence. This interfacing compatibility is yet another reason why we think you will come to really appreciate this parallel FX
Loop fitted to both the DUAL and TRIPLE RECTIFIER Solo Heads.
PAGE 6
The Controls: (Continued)
PRESENCE
MASTER BASS
MASTER
CLEAN
LOOP
ACTIVE
MASTER
LOOP

POWER / ON
This switch delivers the A.C. power to these two RECTIFIER Solo Heads. Make sure the unit is grounded (all
three terminals of the A.C. power cord must be connected whenever possible to avoid injury to the user as well as to the unit) and
that the proper voltage is present. Follow the cold start procedure described in the ON / STANDBY section below
when powering up either your DUAL or TRIPLE RECTIFIER Solo Head.
ON / STANDBY
Perfect for set breaks... this toggle switch also serves an even more important purpose. In the Standby
position the tubes are at idle so that during power up they may warm up before being put to use. Before Power is switched on make
sure the STANDBY switch is in the Standby position. Wait at least 30 seconds and then flip the STANDBY to the ON
position. This prevents tube problems and increases their toneful life substantially.
PAGE 7
FRONT PANEL SWITCHES:
POWER
ON
STANDBY
ON
REST AREA

POWER: SPONGY & BOLD
The two different power selections of both the DUAL and TRIPLE RECTIFIER Solo
Heads are equally important when looking for a particular sound. 'Spongy' works like a built in Variac, reducing all the internal
voltages for a true vintage feeling and that extraordinary 'brown sound.' Power is reduced somewhat
too, making it easier to achieve an overdriven power sound, especially when the Rectifier Select switch
is in the Vacuum Tube position. Using either RECTIFIER Solo Head in this power setting will also
extend tube life and overall reliability, while still producing enough power to work many of your gigs...and
all of your recording needs! With either the DUAL or TRIPLE RECTIFIER'S Power Select Switch
in the up position, maximum power, clean headroom and volume are obtained.
FUSE:
This is the A.C.'s (Alternating Current) main fuse and provides protection from outside A .C. fluctuations as well as power
tube failure damage. Should the Fuse blow, replace it with the same rating in a Slo-Blo type package. The domestic U.S. version
requires a 4 amp Slo-Blo fuse. A power tube short or failure is often the cause of a blown fuse...Follow the cold start procedure
mentioned in the ON/STANDBY switch section and watch the power tubes as you flip the STANDBY to
the ON position. If a power tube is going bad or is arcing you will see it! Flip the STANDBY switch to
Standby immediately and replace the faulty power tube and the fuse if necessary. If you see nothing
abnormal as you lift the STANDBY switch, it is possible that a power tube shorted temporarily and blew
the Fuse. If this is the case it may work again normally. To be extra safe, you might want to replace just the
adjacent tube or all power tubes in the 'shotgun' troubleshooting tradition and save the replaced set as
spares. Spare fuses are a must for the fabled cord bag along with your spare tubes. Always carry both for
they could be worth their weight in gold someday.
RECTIFIER SELECT:
This patented switchable feature allows you to select between two different types of rectifiers for
different sounds and feel. It first appeared on our DUAL RECTIFIER Solo Head and is, in fact, part of the magic behind the
whole Dual Rectifier series of amplifiers. It has since found its way into some of our other products
as well, such as the MAVERICK, HEARTBREAKER and the BLUE ANGEL.Voodoo and
versatility have been added to these products by the inclusion of this cool, patented feature.
SILICON DIODE: (Hi Power) calls up the silicone diode rectifiers offering more punch, a tighter attack with added brightness and
substantially more headroom. This would be the preferred position for loud clean playing or tight rhythmic playing with a high front
end Volume setting (high gain.)
VACUUM TUBE: (Normal) position takes a power section walk down memory lane, paying tribute to those vintage gems of yesteryear.
In those early days of amplification, the only rectifiers available were tubes. Unbeknownst to their creators, these sweet sounding
amplifiers would someday become relics as the demand for higher volumes and more power per package led to the abandonment
of the tube rectifier in favor of the five cent silicone diode's greater efficiency. With this decision went much of the sweetness and
soul, and by the mid 70's, many amps were bold, loud, and efficient, and unfortunately...sometimes lacking some of that earlier soul.
We wanted the Dual Rectifier series to capture that... 'thing' that you... 'can't quite put your finger on...but you know it when it's got
it.' Soul, Personality and Feel. The Vacuum Tube position gives you a sweetness of sound and a liquid feel that simply cannot be
duplicated in any other way. This position shines for single note lead work in either channel and delivers a warm, breathing clean
REAR PANEL:
SPEAKERS
HAND BUILT IN PETALUMA CA.
16 OHM 8 OHM 4 OHM 4 OHM
EXTERNAL
SWITCHING
CHAN.
LOOP
ORANGE
SET TO ORANGE
WHEN USING
FOOTSWITCH OR
EXT. SWITCH
CHANNEL STYLE SELECT
ORANGE CHANNEL GAIN
CLEAN
VARIABLE
HIGH GAIN
RECTIFIER SELECT
4A SB
FUSE
2A
BOLDSPONGY
POWER
RETURN
SEND
SEND LEVEL BIAS SWITCH
6L6 EL-34
CAUTION
BIAS SETTING
MUST MATCH
TUBES IN USE
LOOP SELECT
EXT
SW
RED
AUTO
ORG
AUTO
LOOP ON
ORG & RED
BYPASS
LOOP
IMPORTANT: First, set sounds with
Loop Bypassed. Then set Send,
Mix & Loop Active Master (front) to
50% for unity gain. Loop on, adjust
Send to match FX use Loop Master
as return level & live volume
control, set Mix for effect depth. MIX LEVEL
100% 0%
VACUUM
TUBES
(NORMAL)
SILICON
DIODES
(HI POWER)
120 VOLTS
60 Hz
4 AMPS
SLAVE LEVEL
SLAVE OUT
NORMAL
ORIG TO
MODERN RED TO
VINTAGE
RED
CHANNEL
SELECT
4A SB
FUSE
2A
BOLDSPONGY
POWER
120 VOLTS
60 Hz
4 AMPS
PAGE 8
BOLDSPONGY
POWER
RECTIFIER SELECT
VACUUM
TUBES
(NORMAL)
SILICON
DIODES
(HI POWER)

PAGE 9
RECTIFIER SELECT (Continued)
sound in the Rhythm channel that was previously unavailable in all but the best vintage
amps. If you are like most of the players we know, you'll probably end up leaving your RECTIFIER Solo Head, DUAL or
TRIPLE set to the Vacuum Tube position all the time. Regardless of your preference the RECTIFIER SELECT gives you options
that you won't find anywhere else and versatility that makes both of these amplifiers born vintage performer in any stylistic arena.
NOTE: On the DUAL Solo Head it is possible to run two 6L6 or EL34 tubes by pulling the two center tubes leaving the far left and
far right tubes intact. This procedure reduces the power by approximately 50%. Remove one of the Rectifier tubes if you are using
the Tube Rectifier setting to assure a correct match.
BIAS SWITCH:
Your DUAL or TRIPLE RECTIFIER Solo Head was designed with versatility in mind. So to add to the
already awesome array of on board features...we felt it essential that both of these RECTIFIER Solo Heads be able to adapt its
power output section to use the other classic pentode power tubes, the British style EL 34. These tubes are largely responsible for
the signature sound of many immediately identifiable and wonderful sounding amps created in
Great Britain and used on some of the best recordings to date.
The nature of their sound is usually brighter in the extremely high frequencies...some players find
this almost thin at first. However, aficionados of the EL 34 sound know that nothing has the lushness
of harmonics or spread like a power amp using EL34's. In truth, EL 34's do focus in on a region of
upper harmonics that 6L6's reproduce, but not really enhance in the same way the EL 34's do.
This characteristic is sometimes preferred for sounds that range from a soft clip that would be used for chording or soloing, to an all
out high gain crunch or lead sound. Players that use mostly these types of sounds may prefer the EL 34 clip to the 6L6's that come
standard in both the DUAL and TRIPLE RECTIFIER Solo Heads. If you need a variety of sounds and rely on a clean chording
sound much of the time, you will likely prefer the stock compliment of 6L6's. We feel the 6L6 is a more balanced sounding tube that
produces plenty of harmonic lushness, while at the same time delivering the rich lows that are crucial to both a warm clean sound
and huge, tight high gain crunch sound.
We recommend the 6L6 for reliability: In our many tests and continued use of the currently available EL 34 type power tubes on
the market today, we regret to say that they do not appear to be as rugged in construction as the available 6L6. This is another
reason why your DUAL or TRIPLE RECTIFIER Solo Head was shipped with 6L6 power tubes. If you plan to use the EL 34's
we suggest that you keep a full set of tubes and extra fuses with you during all performances in the event of a tube failure occurring
when using the currently available EL 34's.
Make sure that the BIAS Switch is set correctly to match the tube type that you are using. Failure to
do this will result in tube failure that could possibly burn resistors in the Bias supply. Although this is a fairly simple repair
for an authorized technician, it is easily avoidable. ALWAYS CHECK THE BIAS SWITCH setting if you experiment with
alternate tube types and you will enjoy uninterrupted performances from your amplifier of choice.
FX LOOP:
FX LOOP - SEND & RETURN:
These two 1/4" jacks are the patch point for external signal processing effects. The Effects
Loop in both the DUAL and TRIPLE RECTIFIER Solo Heads is wired in parallel with the unaffected or dry signal which enables
you to preserve the integrity of the all tube tone and feel that either version of this amplifier is capable of
delivering. To use the Effects Loop for your processors, simply connect the Effects SEND jack to your
first effects' INPUT jack. Connect your last effects' OUTPUT jack to the Effects RETURN jack.
The Effects Loop interrupts the signal between the pre-amp and power section. Therefore, the Return
jack can double as a 'Power Amp Input' jack. Remember that the Loop must be engaged for signal to
pass this junction. You will also want to run the MIX Control at 100% to use the Loop as a Power In patch
point.
BIAS SWITCH
6L6 EL-34
CAUTION
BIAS SETTING
MUST MATCH
TUBES IN USE
RETURN
SEND
SEND LEVEL
MIX LEVEL
100% 0%

NOTE: We suggest that when using the power section only of either the DUAL or TRIPLE RECTIFIER Solo Head, that you
have the amp switched to the Vintage Orange channel and the Channel Cloning switch set to 'Normal'. This assures a more neutral
power sensitivity thus making both versions more friendly to use as a power amp.
SEND LEVEL:
This is the master SEND LEVEL Control for the parallel Effects Loop. The inclusion of this control makes it
possible for different channel specific volume levels to be used via the Front Panel channel MASTER Controls, while at the same
time insuring that you will not overload your processors' INPUT stage with an incompatible signal strength.
For the best results, try this method:
1.) Set up the VINTAGE and MODERN channels to your preferred Gain and Tone control settings.
2.) Adjust the individual channel MASTER Controls to the desired listening level.
3.) Set the Rear Panel Effects Loop SEND LEVEL Control so that your processors' INPUT indication
LED is displaying the proper input signal strength ( hopefully unity gain .)
4.) Adjust the Front Panel LOOP ACTIVE MASTER Control to the desired level. See page 5 on: LOOP ACTIVE MASTER - for more
information regarding SEND LEVEL.
LOOP SELECT:
This 5 position rotary type switch determines the status of the Effects Loop. The Loop can be assigned to
either of the channels individually or active at all times (Loop on Org. & Red) It may also be triggered remotely with MIDI controlled
switching devices by connecting the EXTERNAL SWITCHING jacks and selecting EXT. SW. on the Loop
Select rotary. As you might surmise, the ORG. AUTO position assigns the Loop automatically to the
VINTAGE / ORANGE Channel and every time the ORANGE Channel is called up, the Loop will be engaged.
RED AUTO duplicates this scheme for the MODERN / RED Channel. For you purists, both the DUAL
and TRIPLE RECTIFIER Solo Heads gives you the ability to remove all Loop circuitry from the signal
path completely by selecting the BYPASS LOOP position.
SLAVE LEVEL CONTROL :
This 1/4" jack and control provide a signal derived from the speaker jack. Perfect for using
either the DUAL or TRIPLE RECTIFIER Solo Head as a master pre-amp, or additional power amps may be connected for
more power when needed. Some players use this to derive an FX Send Signal and go to other amps for their wet
sound.
NOTE: Once a signal is taken from the Slave, it can not be inserted back into the FX Loop Return jack or a
feedback loop will occur. Much like holding a microphone into the PA system's cabinets...a loud high pitched
squeal will occur.
SPEAKERS:
Two 4 Ohm, one 8 Ohm and one 16 Ohm jack are provided for speaker interfacing. Both DUAL and TRIPLE
RECTIFIER Solo Heads are not very sensitive to speaker mismatches and will not be
damaged by them, except that very low ohmage loads will cause the power tubes to wear
faster. A single twelve-inch 8 Ohm speaker should generally be connected to the 8 Ohm
output. When using two 8 Ohm speakers, connect them both to the 4 Ohm outputs provided
(because the total load is 4 Ohms in that case.) Check out the information further back in
this manual regarding speaker impedance and possible speaker hook-up schemes.
PAGE 10
REAR PANEL: (Continued)
RETURN
SEND
SEND LEVEL
MIX LEVEL
100% 0%
LOOP SELECT
EXT
SW
RED
AUTO ORG
AUTO
LOOP ON
ORG & RED
BYPASS
LOOP
SLAVE LEVEL
SLAVE OUT
SPEAKERS
4 OHM 4 OHM16 OHM 8 OHM

PAGE 11
REAR PANEL: (Continued)
16 OHM 8 OHM
EXTERNAL
SWITCHING
CHAN
LOOP
SPEAKERS
HAND BUILT IN PETALUMA CA.
4 OHM4 OHM
ORANGE
RED
CHANNEL
SELECT
SET TO ORANGE
WHEN USING
FOOTSWITCH OR
EXT. SWITCH
CHANNEL STYLE SELECT
NORMAL
RED=MODERNORG=VINTAGE
ORG TO
MODERN
RED TO
VINTAGE
SPEAKERS: (Continued)
4x12 cabinets may be 4, 8 or 16 Ohms. If you are not sure of the impedance of your cabinet, you
may need to remove the Rear Panel in order to verify the impedance rating of the individual speaker or speakers. Mesa/Boogie
4x12 and 4x10 cabinets come standard wired to 8 Ohms, and are wired in series-parallel. Some Non-Mesa 4x12 cabinets are wired
16 Ohms using four 16 Ohm speakers. By wiring all four speakers in parallel, you can reduce the cabinet to an impedance load of
4 Ohms (assuming the speakers are 16 Ohms each.) No matter how unusual your speaker setup, it is always possible to get good
performance.
EXTERNAL SWITCHING JACKS:
These jacks allow ( usually MIDI-programmed ) operation of your amplifier's functions
from an external switching source. In either case, the switching is accomplished by
connecting ( 'shorting' ) the jack's 'Tip' to its 'Ring' (or ground.)
CHANNEL STYLE SELECT :
This circuit (patented) makes possible a concept, so inherently right, that in it's simplicity it was
long overlooked. To be able to set a group of controls in a given channel of a two channel amplifier - to duplicate that channel and
that control setting, (save for maybe one or two controls,) in another separate channel of that same amplifier. Sound simple? Well it
would be, but most, if not all amplifiers, must use the available internal space to offer circuitry and
Front Panel real estate for alternate channels that vary greatly in both gain structure and tonality.
CHANNEL STYLE SELECT is our answer to this channel expanding idea. By providing two identical
groups of Front Panel controls and interfacing each of them to it's own different and dedicated channel,
we achieve the Vintage Orange and Modern Red channels. Sophisticated internal switching circuitry
then enables you, the user, to utilize the channels for their differences - 'Normal' or; with a flick of the
switch - Clone them 'Orange to Modern' or 'Red to Vintage.' This allows for virtually any combination of
your two favorite sounds to be footswitchably possible even if they are normally found in the same channel! CHANNEL STYLE
SELECT greatly enhances the versatility of both the DUAL and TRIPLE RECTIFIER Solo Heads live or in the studio, while
retaining its clean Front Panel layout.
NOTE: When the CHANNEL STYLE SELECT feature is used and the Modern Red channel is cloning Red to Vintage (so that it
sounds like the Orange channel) - be aware that both the Orange and Red channels' PRESENCE Controls are active in the (bottom)
Red channel in this setting only. Some amazing sounds are possible because the two PRESENCE Controls maintain their respective
voicing differences giving you two regions of top end harmonics to play with in this Mode.
CHANNEL SELECT :
This switch simply allows you to switch between the two channels (Vintage/Orange and Modern Red)
without using the Channel Select Footswitch or, when one is not available. To use the footswitch however,
the Channel Select switch must be in the up (ORANGE) position.

MASTER GAIN TREBLEMIDPRESENCE BASS
INPUTFT.SW
LOOP
ACTIVE
MASTER
MASTER GAIN
TREBLEMIDPRESENCE BASS
INPUTFT.SW
LOOP
ACTIVE
MASTER
MASTER
INPUTFT.SW
LOOP
ACTIVE
MASTER
INPUTFT.SW
LOOP
ACTIVE
MASTER
GAIN
TREBLEMIDPRESENCE BASS
MASTER GAIN
TREBLEMIDPRESENCE BASS
Orange Channel Gain - Variable High
Orange Channel Gain - Variable High
FACTORY SAMPLE SETTINGS
SAMPLE 4 Orange Crunch / Molten Red
SAMPLE 2 Purring Blues
SAMPLE 3 Liquid Metal / Tight Mosh
SAMPLE 1 Clean Orange Channel Gain: Clean
Rhythm
Spongy or Bold
Tube Rectifier.
Power Section:
Bold
Solid State Rectifier
Power Section:
Orange Channel Gain: Variable
High Gain
PAGE 12

INPUTFT.SW
LOOP
ACTIVE
MASTER
INPUTFT.SW
LOOP
ACTIVE
MASTER
INPUTFT.SW
LOOP
ACTIVE
MASTER
INPUTFT.SW
LOOP
ACTIVE
MASTER
MASTER GAIN
TREBLEMIDPRESENCE BASS
MASTER GAIN
TREBLEMIDPRESENCE BASS
MASTER GAIN
TREBLEMIDPRESENCE BASS
MASTER GAIN
TREBLEMIDPRESENCE BASS
SAMPLE 1 Power Section:
SAMPLE 2 Power Section:
SAMPLE 3 Power Section:
SAMPLE 4 Power Section:
PERSONAL SAMPLE SETTINGS
PAGE 13

PAGE 14
INPUTFT.SW
LOOP
ACTIVE
MASTER
INPUTFT.SW
LOOP
ACTIVE
MASTER
INPUTFT.SW
LOOP
ACTIVE
MASTER
INPUTFT.SW
LOOP
ACTIVE
MASTER
MASTER GAIN
TREBLEMIDPRESENCE BASS
MASTER GAIN
TREBLEMIDPRESENCE BASS
MASTER GAIN
TREBLEMIDPRESENCE BASS
MASTER GAIN
TREBLEMIDPRESENCE BASS
SAMPLE 1 Power Section:
SAMPLE 2 Power Section:
SAMPLE 3 Power Section:
SAMPLE 4 Power Section:
PERSONAL SAMPLE SETTINGS

6L6 or EL34
RECTIFIER TUBES
12AX7
(5)
V 4 V 3 V 2 V 1
V 5
PARTIAL VIEW OF CHASSIS
BACK EDGE OF CHASSIS
DUAL RECTIFIER
Solo Head TUBE TASK CHART
B A B A
B A
B A B A
(Each 12AX7 contains two separate Triodes)
5U4G
V1 A= Input Stage V1 B Not Used V2 A= 2nd Stage V2 B= 3rd Stage V3 A= 4th Stage
V3 B= 5th Stage V4 A= FX Send V4 B= FX Return V5 A= V5 B= Phase Splitter /
Output
Description of Tube Functions
PAGE 15

PAGE 16
6L6 or EL34
RECTIFIER TUBES
PARTIAL VIEW OF CHASSIS
BACK EDGE OF CHASSIS
TRIPLE RECTIFIER Solo Head TUBE TASK CHART
12AX7
(5)
V 4 V 3 V 2 V 1
V 5
B A B A
B A
B A B A
(Each 12AX7 contains two separate Triodes)
5U4G
V1 A= Input Stage V1 B Not Used V2 A= 2nd Stage V2 B= 3rd Stage V3 A= 4th Stage
V3 B= 5th Stage V4 A= FX Send V4 B= FX Return V5 A= V5 B= Phase Splitter /
Output
Description of Tube Functions