Mesa boogie MARK III User Guide

MESA-BOOGIE MARK III
OPERATING INSTRUCTIONS

MESA ENGINEERING

CONGRATULATIONS! You've just become the proud owner of the world's finest guitar amplifier. When people come up to compliment
you on your tone, you can smile knowingly ... and hopefully you'll tell them a little about us! This amplifier has been designed, refined
and constructed to deliver maximum musical performance of any style, in any situation. And in order to live up to that tall promise, the
controls must be very powerful and sophisticated. But don't worry! Just by following our sample settings, you'll be getting great sounds
immediately. And as you gain more familiarity with the Boogie's controls, it will provide you with much greater depth and more lasting
satisfaction from your music.

THREE MODES
For approximately twelve years, the evolution of the guitar amplifier has largely been pioneered by MESA-Boogie. The Original Mark I

Boogie was the first amplifier to offer successful lead enhancement. Then the Mark II Boogie was the first amplifier to introduce
footswitching between lead and rhythm. Now your new Mark III offers three footswitchable modes of operation: Rhythm 1, Rhythm 2
and Lead.

Rhythm 1 is primarily for playing bright and sparkling clean (although a little crunch is available by running the Volume at 10). You
might think of Rhythm 1 as "the Fender mode”.

Rhythm 2 is mainly for crunch chords, chunking metal patterns and some blues (but low settings of the Volume 1 will produce an
alternate clean sound that is very fat and warm). Think of Rhythm 2 as "the Marshall mode".

The third mode is by far the most radical, and its two separate knobs will deliver the most lethal crunch or the smoothest, most vocal
sounding lead sustain. This mode is pure MESA-Boogie. Try as they might, no one else can touch this sound!

THE CONTROLS
Let's review the controls now, one at a time, to learn their various functions and see how they interact. Remember that the settings

listed are approximate.
VOLUME 1 This control is active in all three modes. It establishes the amplifier's basic gain, or sensitivity

players find a "sweet spot" around 7 which enables the amp to footswitch best between all three modes. Generally speaking, you
should find the highest setting possible that still gives you the desired degree of cleanliness in the Rhythm 1 mode. This allows you to
have the strongest possible signal feeding into the other two modes.

The response of the Volume knob increases rapidly above 7. You can also back off your guitar's volume slightly if you want to run the
amp Volume higher or if your pickups are real hot. Adjusting your pickup height from the fret board can make a big difference. Higher
settings (of everything) unleash a stronger response from Rhythm 2. All-out metal die-hards (who probably won't use Rhythm 1
anyway) may want to dial the Volume up to 9 or 10 for a heavy grinding "krang" similar to a great (or customized) Marshall. And yet
lower settings of the Volume will enable both rhythm modes to play clean, each with its own distinctive voicing.

The PULL BRIGHT adds sparkle to a clean Rhythm 2 sound and adds shimmer to a clean Rhythm 1 sound, producing the ultimate
Fendery Strat sound for funk riffs, country and pop rhythm playing. The effect of the Pull Bright diminishes as Volume 1 is turned up
and has no effect when the Volume is at 10

to your guitar's output. Most

RECOMMENDED SETTING: 7, pulled out.

TREBLE This control is the most powerful of the three tone controls. At high settings (8 and above) it will minimize the effect of the
Bass and Middle, but they will become the stronger controls when the Treble is below 5. Again, most players find a sweet spot in the 6
to 8 range. Along with the Volume 1 sweet spot, these are the two most critical settings for maximum footswitching performance in all
three modes. The most hardcore metal tones may come at higher settings than the best jazz tones--but we have yet to find a player
who needs to footswitch instantly back and forth from Wes Montgomery to Motorhead! So don't worry about these sweet spots being
too restrictive or too hard to find. Many players alternate between Lead and just one or the other of the Rhythm modes. And top 40
players usually have no trouble switching among all three modes. All players can, of course, enhance performance by switching
pickups and/or adjusting their guitar's volume control.

The TREBLE SHIFT is one of the programmable controls. When pulled out, the effect becomes linked to the footswitch control buss
and automatically increases the upper-midrange drive in the Lead Mode only Treble Shift has no effect in either of the rhythm modes.

RECOMMENDED SETTING: 7, pulled out.
BASS This is a wide-ranging control that is very easy to use. Most players prefer to operate the Bass in the 0 to 4 range, pulled out for

single coil and pushed in for humbucking pickups. Higher settings of the Bass are good with very bright guitars like Telecasters, but
excess settings of Bass (especially with Humbuckers) can cause the Lead sound to become tubby and blurred.

RECOMMENDED SETTING: with Strat type, 4, out; with dual coil, 0-2.
MIDDLE This is the weakest of the three tone controls. Although its action may not seem dramatic, it will add in mid-range warmth

under normal settings of Treble and Bass. Its Pull-Switch activates the Rhythm 2 circuitry, which can also be controlled by the (optional)
Rhythm 2 footswitch. Top 40 players and others who need to footswitch between all three modes will definitely want this footswitch.
Many other players are content to footswitch between a clean and a lead (Rhythm 1 to Lead) or between a crunch and a lead (Rhythm
2 to Lead). When this is the case, the standard Lead/Rhythm footswitch can be used for switching back and forth while the appropriate
rhythm mode is selected by the pull switch on the Middle control.

RECOMMENDED SETTING: 5.
MASTER This control regulates the overall amplifier loudness and it remains functional in all modes. If it is set extremely low, it will

seem to reduce the loudness available from the Lead Mode. This is normal and not a problem since it can help to spread out the action
of the Lead Master. And at any setting, it is still possible to adjust the Lead Master so it can be louder, softer or the same as the
Rhythm loudness. When switching to Rhythm 2, automatic circuitry maintains the same level of Effects Send strength and loudness so
that a separate "Rhythm 2 Master" is not required.

The PULL DEEP built into the Master, is another simple and self explanatory control. Its main usefulness is in adding fatness and body
to single coil pickups.

RECOMMENDED SETTINGS of Master: usually around 1/2 to 3 1/2, rarely over 5 and never above 6 unless the Volume 1 and Lead
Drive controls are being turned down at the same time. At Master settings above 3, the Lead Bright should be pushed in.

LEAD DRIVE This knob adjusts the gain, sustain and sensitivity of the Lead Mode. Although it is responsive to the setting of Volume 1,
its range is so great that there is usually more than enough drive available regardless of how low Volume 1 is set. At very low settings
of Lead Drive it is still possible to obtain a relatively clean sound in the Lead Mode. Moderate settings (around 2 to 3, Treble Shift in)
produce a good blues sound...like a Fender turned up full ... and yet the authentic stringy sound of the guitar still comes through. As the
Lead Drive is increased, an entire musical range of great sustain and rich distortion harmonics is produced.

The PULL switch built into the Lead Drive control duplicates the function of the Lead/Rhythm footswitch. This separate switch is a
useful backup in case you lose your footswitch box or just don't need to change modes very often. The footswitch will work only when
the Lead Drive control is pushed in.

RECOMMENDED SETTING: Your choice-try 5.
LEAD MASTER This control regulates the loudness and is active in the Lead Mode only. Because it works at the same time as the

regular Master, whichever one is set lower will determine the maximum Lead Mode loudness. Its built-in Pull-Bright is only active for the
Lead Mode and is intended to add brightness when playing at softer volumes. As the amplifier is turned up louder and the power stage
begins to clip, the added brightness from the Lead preamp may cause premature squealing without adding any benefit to the tone--so
push it in when playing loud. This is especially true when Rhythm 2 and Lead are on at the same time.

GRAPHIC EQUALIZER
This optional feature is lots of fun to use and it certainly does expand the Boogie's tonal flexibility. (But for those of you who prefer the

fewest possible knobs and controls - don't worry! All the R & D of the Mark III's tone performance is religiously made without using the
optional EQ. This prevents it from becoming a necessity.) Although there are a thousand different ways to set the Graphic, I want to
point out the single most useful: we call it "the classic V" because that's what it looks like. Move the first and last sliders about
three-forths of the way up. Move the second and forth sliders two-thirds of the way up. Move the center slider about three quarters of
the way down...then fine tune your sound using just this center slider.

You'll hear how a slight adjustment at the 750 hz position makes a dramatic difference in the sound, whether you're playing with
moderate distortion, heavy distortion or perfectly clean. This setting makes the amp seem even bigger, bolder, stronger and fatter. If
you have a friend with a Marshall stack, you can easily drive him to total despair by sounding bigger, stronger, louder, better, etc. with
just your 1x12 Boogie! Try it, it's great fun to watch his ego short-out when his monster sounds puny next to your little Boogie!

EQ SWITCHING
The Boogie also offers great flexibility for switching-in the Graphic Equalizer. The front panel toggle switch offers three choices: EQ

OUT, EQ IN (all the time), and EQ AUTO. In the AUTO mode, your Equalizer is programmed to switch-on automatically when you go
into the Lead Mode. A final switching choice is to use the optional EQ Footswitch which plugs into the back of the chassis. With it, you
can click on the EQ at any time, regardless of how the toggle switch is set.

STANDBY SWITCH
The Standby toggle switch turns off the high voltages inside your Boogie. You can use this switch to let your amp "cool off" during

breaks while keeping the tube filaments warm. This is actually less strain on the tubes and electronics than turning your Power Off
during breaks.

POWER SWITCH
This is the AC On/Off switch for the whole amplifier ... only the AC convenience outlet on the back remains energized when the Power

is Off. Recommended turn-on procedure: Have the amp in the Standby position when switching up the Power toggle. Wait 30 seconds
or so for the tube filaments to warm up, then turn the Standby to On. This prevents a high voltage surge from hitting the cold tubes and
also helps reduce the strain on capacitors and other internal parts.

REAR PANEL FEATURES
FUSE
Should your Boogie blow a fuse, be sure to replace with Slo-Blo, same amperage. By far the most likely cause of a blown fuse is a bad

power tube. For further information, see the Service & Maintenance Guide.

GROUND
This switch is often helpful in reducing buzzes which originate in the AC power wiring outside the amplifier. We recommend leaving the

switch in its center OFF position unless position A or B definitely helps. In the center OFF position, your Boogie cannot be the source of
annoying "ground shocks" to the microphones etc.

DIRECT
Previously known as the SLAVE, this feature provides a variable strength signal right from the speaker

supplied, all Effects and Reverb are included, and there is absolutely no loss of the Boogie's tone when running from the Direct to a
mixing board or another amplifier. (Many players will still prefer a microphone "listening" to their speaker coloration.) In some
sophisticated set-ups, players run their Direct into their Effects Rack and then from the Effects into other, external amplifiers. But such a
set-up cannot route the Effects output back into the original Boogie. Also note that a speaker or load resistor should be plugged into a
Speaker jack when using the Direct. Load resistor value...though not critical ... can change the overall tone. Suggested value: 8 ohms,
50 watts minimum. And note that this resistor will get quite hot when running the Boogie "up loud" for long periods.

EFFECTS SEND & RETURN
The Effects Loop circuitry of the Mark III is very sophisticated and works very well with nearly all units. The maximum signal strength

obtainable is around 0.6 volts RMS, or about the same as a guitar pickup. Only the lowest quality, cheap digital delays may experience
some overload and we feel the problem here is caused by poor effect design, which would cost only pennies to remedy. Worst
offenders: Roland SDE 1000, Effectron Jr. Please call Roland or Delta to complain ... not us! Suggest that they "pad their input and
buffer their output", as the real world requires! However, it is possible to further lower the Boogie's Effect output strength but not without
increasing the noise and sacrificing some tone. For those who wish to do this we recommend changing resistor R230 from 6.8K to

4.7K. R230 can be located by following the Black wire from the Send jack back to the circuit board. In the Rhythm modes the Volume 1
control determines the Effects Send level, and in the Lead mode, it is the Lead Master. By running the Master 1 higher and these two
controls lower, you can improve the performance of sub-standard effects.

PRESENCE
This control sets up the basic brightness of the overall tone. But unlike a tone control, the Presence acts on the output and driver

circuits, not the preamp. Season to your liking; recommended setting about 7.

jack This way better tone is

REVERB
Like the Presence, this control is located on the rear panel of short chassis amplifiers ... because there's no more room on the front and

they seldom require adjustment. The Mark III's reverb is by far the best we've ever had; its performance is hard to equal even with
expensive outboard effects. And the Reverb Footswitch also works uniquely: rather than merely switching the Reverb on and off, it
allows you to maintain a good background level then footswitch up to a dramatic, fully drenched reverb for a special effect.

SPEAKERS
One 8-ohm and two 4-ohm jacks are provided. The Boogie is 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 out faster. A single twelve-inch 8-ohm, speaker should
generally be connected to the 8-ohm output on the amp. 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).

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 to
see what ohmage the individual speakers are. Most Marshall 4x12 cabinets are 16 ohms. By wiring all four speakers in parallel, you
can reduce the cabinet impedance to 4 ohms (assuming the speakers are 16 ohms each). A MESA/Boogie 4x12 cabinet comes