68 Plexiglas 50W
Headrush Amplifiers

68 Plexiglas 50W

Inspired by Marshall Super Lead Plexi 50W

The model 68 Plexiglas 50W is an amplifier inspired by classic vintage Plexi, designed to offer:

  • Powerful, bright and dynamic sound at 50 watts
  • Ideal for classic rock, blues and hard rock
  • Perfect for single coil or humbucker guitars, also great with overdrive/boost pedals

Includes Treble, Middle, Bass, Presence, High Volume, Normal Volume and Output Level controls, for shaping tone, saturation and dynamics.

BluesRockHard RockBassClassic Rock

Controls

Treble

Control the high frequencies:

  • Low → smooth sound
  • High → bright and punchy
  • Match the tone to the pickup and mix
Middle

Controls mid frequencies:

  • Low → scooped sound
  • High → fuller and more present
  • Affects punch and definition
Bass

Control the low frequencies:

  • Low → more defined and tight
  • High → full and full-bodied
  • Ideal for 35–55% for balanced sound
Presence

Control brilliance and final definition:

  • Low → soft sound
  • High → bright and punchy Modulate presence and attack in the mix
High Volume

Controls the level of the “High” channel:

  • Low → light
  • High → powerful and more saturated Interacts with EQ and Presence
Normal Volume

Controls the level of the “Normal” channel:

  • Low → clean
  • High → light crunch Useful for modulating dynamics and tone
Output Level

Controls the final volume of the amplifier:

  • Negative → attenuation 0 d
  • B → neutral level
  • Positive → boost of the final signal Does not alter the timbre, only the overall level

Pro Tips

BEHAVIOR OF THE AMPLIFIER

  • Powerful, bright and dynamic sound at 50W
  • Precise response to guitar touch and volume
  • EQ + Volumes → define body, brightness and saturation
  • Output Level → balances the overall volume of the effect chain

Advice:

  • High Vol + Treble → brilliance and crunch
  • Middle + Bass → body and presence
  • Normal Vol → clean channel
  • Output Level → balances with other pedals/amps

Final advice:

  • High Vol + Treble → define brilliance and crunch
  • Middle + Bass → control body and presence
  • Normal Vol → manages the clean channel
  • Output Level → balance the sound with other pedals or amplifiers

Setup Examples

Clean vintage

Treble50%
Middle45%
Bass40%
Presence50%
High Vol40%
Normal Vol40%
Output Level0dB

Crunch / blues

Treble55%
Middle50%
Bass45%
Presence55%
High Vol55%
Normal Vol50%
Output Level+1 dB

Powerful lead / saturation

Treble60%
Middle50%
Bass45%
Presence60%
High Vol65%
Normal Vol55%
Output Level+2 dB