Mesa/Boogie Mark IV Amplifier User Manual

PAGE 3
Setting the RHYTHM 1 mode adjusts the input sensitivity for the clean RHYTHM mode. With most guitars, this mode stays clean until
around 8 where it begins to overdrive. Use the R1 MASTER to control loudness if you want slight overdrive at low volumes. This mode
was very carefully designed to provide great rhythm sounds, from the best of vintage, Fender-type (clean or solo)
to a more modern, shimmering “funk rhythm” sound. Be sure to try this mode played really loud; you’ll love it for
blues or rock. (See the “Traditional Blues” setting on the Sample Settings sheet found on page 15 of this manual.)
This function adds shimmer and sparkle to your sound when activated. Note that the amount of added brightness varies with the R1
GAIN setting: more brights at lower settings, less at higher. For super shimmer, run the GAIN at around
3
or
4
with the BRIGHT pulled out. For the most naturally balanced sound, run the GAIN at around
6
or
7
with the
BRIGHT pulled.
This control dials in the MARK IV’S predominate tonal characteristic. In the
0
to
3
range, a dark, warm jazz tone is obtainable.
Most common settings are in the
5
thru
7
range and note how the overall “gain” of the mode increases with higher TREBLE
control settings. This is because so much of the energy of the musical spectrum is channeled
through this most powerful tone control. As this is true for all modes, the MARK IV includes three
separate TREBLE controls.
These are the only shared tone controls aboard the MARK IV. Because of internal circuitry changes which occur when switching
modes, you will most likely find R1’s optimum setting works well for RHYTHM 2. The effect of these two tone controls is largely
determined by the setting of the TREBLE controls. Only when the TREBLE control is set very low (or off) are the BASS and MID
controls really strong.
At normal TREBLE control settings, their effect is greatly diminished and they serve mainly to round
out and fill up the overall tone. Do note however, that setting the BASS control too high can result
in unwanted flubbiness, especially in RHYTHM 2. The recommended setting for the BASS control
is
0
to
3
and for the MID control it is
4
to
7
.
RHYTHM 1 GAIN:
RHY1 GAIN
INPUT
PULL BRIGHT
INSTRUMENT
2
3
4
7
8
9
1
0
10
6
5
PULL BRIGHT:
RHY1 GAIN
PULL BRIGHT
2
3
4
7
8
9
1
0
10
6
5
CONTROLS:
RHYTHM 1 TREBLE:
RHY2 GAIN
PULL FAT
RHY1 GAIN
PULL BRIGHT
R1 TREBLE
2
3
4
7
8
9
1
0
10
6
5
2
3
4
7
8
9
1
0
10
6
5
6
2
3
4
5
7
8
9
1
0
10
R1 + R2 BASS & R1 + R2 MID:
R1+ R2 BASS
6
2
3
4
5
7
8
9
1
0
10
R1+ R2 MIDR1TREBLE
2
3
4
7
8
9
1
0
10
6
5
2
3
4
7
8
9
1
0
10
6
5

Mesa/Boogie Mark IV Amplifier Specifications

General

Brand	Mesa/Boogie
Model	Mark IV Amplifier
Category	Musical Instrument Amplifier
Language	English

Summary

Safety Precautions

General Safety Guidelines

Essential precautions for safe operation, handling, and electrical safety.

Amplifier Overview and Layout

MARK IV Introduction

Introduction to the amplifier's design, heritage, and capabilities.

Front Panel Layout

Visual identification of all front panel controls and their locations.

Rear Panel Layout

Visual identification of all rear panel connections and switches.

Front Panel Controls

Power-Up Procedure

Step-by-step guide for safely powering on the amplifier.

Rhythm Mode Controls

Detailed explanation of controls for Rhythm 1 and Rhythm 2 channels.

Lead Mode Controls

Detailed explanation of controls for the Lead channel.

Master, EQ, and Power Controls

Explanation of Master Volume, Graphic EQ, Output Level, Standby, and Power modes.

Rear Panel Connections and Configuration

Power and Output Jacks

Details on AC receptacle, fuse, speaker jacks, and recording/slave outputs.

Switching and Connectivity

Explanation of effects loop, satellite connections, mode selector, and external jacks.

Power Amp Modes

Information on Triode/Pentode and Simul-Class/Class A power amp selections.

Tube Substitution

Guide for replacing and substituting power tubes.

Troubleshooting and Maintenance

Tube Noise and Microphonics

Diagnosing and resolving issues related to tube noise.

Power Tube Failures

Identifying and addressing problems with power tubes.

Pre-Amp Tube Issues

Diagnosing and resolving minor pre-amp tube noise problems.

Bias Adjustment Explained

Detailed explanation of bias adjustment concepts and procedures.