Safety First

  • Always power off and unplug before inspecting
  • Let tubes cool before touching (they get VERY hot)
  • This amp contains high voltages that can be lethal - don't open the chassis
  • Never operate without speakers connected

No Sound? Check These First

Basic Connections

  • Is the power light on?
  • Is the STANDBY switch in the ON position? (Remember to wait 30-60 seconds after turning on power)
  • Is your guitar cable securely connected to the correct channel?
  • Try both channels (VINTAGE and CUSTOM) to isolate the issue
  • Are the volume knobs turned up? (Each channel has its own volume)
  • If using pedals, try connecting your guitar directly to the amp

Still No Sound?

  • Try a different guitar cable
  • Try a different guitar
  • Check if one channel works but not the other
  • If using the effects loop (in the back), bypass it

Sound Problems

Weak or Thin Sound

  • Check the BASS, MIDDLE, and TREBLE settings
  • Make sure BRIGHT switch isn't causing issues (Custom channel)
  • Check if both 10" speakers are working
  • Ensure proper impedance matching if using external speaker cabinet

Distorted or Fuzzy (When Not Wanted)

  • Turn down the volume (Vibrolux breaks up naturally when pushed)
  • Check tubes for visible issues (blue glow or white spots)
  • Try the other channel
  • Check if output tubes are biased properly (requires technician)
  • Bass-heavy guitars can cause unwanted breakup - adjust EQ

Reverb or Tremolo Not Working

  • Check if the Reverb knob is turned up
  • Make sure footswitch is connected properly (if using one)
  • Test both Speed and Intensity controls for tremolo
  • Note: Reverb and tremolo can be subtle at lower settings
  • Try both channels (reverb/tremolo character differs between channels)

Noise, Humming or Buzzing

  • Move away from lights, computers, and neon signs
  • Try a different power outlet
  • Check guitar cable connections
  • Some hum is normal for tube amps (especially at high volumes)
  • Check if noise changes when touching metal parts of guitar (grounding issue)

Channel-Specific Issues

Vintage Channel Problems

  • This channel is based on the "silver face" Vibrolux
  • Normal to have a tighter bass response and scooped mids
  • Reverb has a classic drip, especially with single coil pickups
  • If too bright, roll back guitar tone control

Custom Channel Problems

  • This channel is based on Bassman tone stack
  • Normal to break up earlier with more midrange
  • Bright switch might be too aggressive with some guitars - try disengaging it
  • Reverb is typically darker and thicker on this channel

Power Issues

Won't Turn On

  • Check if it's plugged in
  • Check the fuse (behind power connection)
  • Try a different power outlet
  • Make sure power switch is fully engaged

Standby Switch Issues

  • Always wait 30-60 seconds after turning power on before switching to Standby ON
  • If amp goes silent when switching to Standby ON, check output tubes
  • Intermittent sound when moving Standby switch could indicate a dirty switch

Keeps Cutting Out

  • Ensure proper ventilation (tube amps run HOT!)
  • Check for loose tubes (with amp OFF and unplugged)
  • May have dirty tube sockets (requires service)
  • Could be a failing tube (especially if intermittent)

When to Get Professional Help

  • If it makes popping or crackling sounds that won't stop
  • If it smells like burning or you see smoke
  • If tubes are glowing bright blue/purple or have white spots
  • If it blows fuses repeatedly
  • If it makes a loud "motorboating" sound
  • If you see arcing or sparking anywhere in the amp

'68 Custom Vibrolux Settings Cheat Sheet

For Clean Fender Tones

  • Channel: VINTAGE
  • Volume: 3-4
  • Treble: 6-7
  • Middle: 5-6
  • Bass: 4-5
  • Reverb: To taste (2-4 for subtle, 5-7 for surfy)
  • Tremolo: Speed 3-4, Intensity 4-5
  • Note: Sweet spot is around 3-4 on volume before breakup begins

For Edge-of-Breakup Blues

  • Channel: CUSTOM
  • Volume: 5-7 (pushes preamp tubes into compression)
  • Treble: 5-6
  • Middle: 6-7
  • Bass: 3-4
  • Bright Switch: Depends on guitar (OFF with bright single coils)
  • Use bridge pickup on guitar
  • Roll back guitar volume for cleaner sound

For Pedal Platform

  • Channel: VINTAGE
  • Volume: 3-4 (keeps headroom for pedals)
  • EQ: Set flat (all at 5)
  • Reverb: Minimal (0-2) if using reverb pedals
  • Place dirt pedals before amp, time-based effects in effects loop if possible

For Classic Rock Crunch

  • Channel: CUSTOM
  • Volume: 7-8
  • Treble: 6
  • Middle: 7
  • Bass: 4
  • Bright Switch: OFF
  • Reverb: 2-3
  • Use bridge pickup or humbucker pickups if available

For Maximum Reverb & Tremolo

  • Channel: VINTAGE for wet, splashy reverb; CUSTOM for thicker reverb
  • Reverb: 7-10
  • Tremolo Speed: Adjust to song tempo
  • Tremolo Intensity: 6-8
  • Volume: 3-5 to stay cleaner with effects
  • To synchronize tremolo with music, tap your foot to the beat and adjust speed until it matches

Do you need more help with this?

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