Based on the MESA/Boogie® Mk IV
Mesa Boogie Mark IV Combo of 85 watts Class A or Simul-Class (depending on the type and arrangement of the power valves you can also deliver 70, 50 or 30 w). Mesa Boogie Mark IV A Celestion C90 12 “speaker. 3 independent channels with different response modes. 5-band graphic equalizer switchable and auto assignable to R2 and Lead channels. Mesa Boogie Mark IV. Record outputs, line, & amp; nbsp; Reverb .. 5 valves 12AX7 in the pre. 4 valves 6L6 power; Selector of power valves like pentode or triode. Variac for normal (Full Power) or classic (Tweed) response.
In 1984, Mesa / Boogie released the first “Tri-modal” amplifier, the Mark III. Tri modal, because it has separate modes for Clean sound, Crunch sound and Lead sound. The Mark IV, which came out six years later, significantly improved the ability to control each channel separately by introducing two controller knobs on the front panel, thus optimizing available space without increasing the Mark III’s comfortable and versatile size. It is a complete amplifier, has all ranges, from blues, jazz, rock, heavy, even metal, has immense possibilities and just so make it especially complicated.
Rythm1 Gain-Rhythm 1 Gain and Pull Bright
This control defines the sensitivity of the clean channel, in settings on the 8, it starts to cause distortion, but in general it is clean crystalline. When it is saturated, it gives the sensitivity to the right hand of the guitarist, like to play blues, although for that is the channel Rhythm 2.
Pull Bright: Adds brilliance to the sound. With Rhythm 1 in low values (from 4 down), you add a lot of brilliance. At high settings (from 7 upwards), little brightness.
Rythm2_Gain-Rhythm 2 Gain and Pull Fat
It controls the gain of channel 2. It is a very powerful control; In low values, between 1 and 4, we can get a low saturation, which allows us to play blues and be able to control it only by striking loudly or slowly to the guitar string, an alternative clean channel.
But in high values (from 5 upwards), we can achieve a second Lead sound for our solos. With much gain and sustain.
Pull Fat: When it is deactivated it is possible to achieve blues sounds by controlling the channel only with gain and presence control, but if I want something closer to rock or heavy metal, you have to activate this control and raise the gain to values as high possible. It is a very useful tool when it comes to being versatile.
The Mark IV has three separate and independent treble controls. One for each channel. It is a very powerful control, with much to do with the amount of gain of each channel. It directly influences this, and it is no less, because most of the sound energy in this ampli is routed to be controlled with these three seemingly insignificant little perches.
Let’s see it neatly, first the controls for the two Rhythm channels, then for the Lead channel:
-R1 Treble, R2 Treble and R1 + R2 Bass & amp; amp; Mid
-Rhythm 1 Treble
Between 0 and 3, it gives a warm jazzy tone, but most people occupy it between 5 and 7. That would be a mid-point to play pop, rock. This control passes a lot of sound energy and defines the sound of the channel to a great extent. It’s essential.
-R1 + R2 Bass & R1 + R2 Mid (Low and Medium for channels 1 and 2)
These controls regulate the amount of bass and half of the two channels at once Rhythm1 and Rhythm2. They are the only shared controls on the Mark IV.
These controls depend largely on how the Treble of the two channels is set. If the Treble is too high, these bass and midi controls become subtle and do not produce much change in overall pitch. Now, the lower the Treble is set, the lows and midpoints will be highlighted. However Bass and Middle controls serve to round the sound and give it a bit more definition. Therefore Treble must work well first and then round with low and medium.
-Rhythm 2 Treble
It works very much like Rhythm 1 Treble, while higher, more gain and sustain for the channel, while in low values the controls of Bass and Mid predominate, giving more warmth to the sound. This control must be handled in conjunction with the presence control corresponding to the channel.
There is a presence control for each channel in this amplifier. The presence usually refers to an enhancement of the mid-treble and a little bass. The more presence, it will sound brighter and warmer at the same time with a little more definition. At lower presence, a more opaque sound is achieved.
The Rhythm2 and Lead channels have a “Pull” function. If one pulls the knob out, the presence control acts on a higher frequency range, allowing a more sharp sound to help us to excel