Follow Us: Facebook  myspace  Twitter  YouTube  
You Are Here:   Modifications ... Amp Modifications ... Discontinued Mods ... Marshall JCM900 Mods ... Marshall JCM900 4500 Mods ... Marshall JCM900 4500 Rock Mod



Discontinued – We no longer modify these amplifiers.Various factory issues have proven time consuming to resolve/repair. To date we have absorbed a great deal of time/cost associated with repair(s) of these models, however we can no longer continue to do so & nor do we wish to charge customers for costly repairs. Please note; our Mods do not cause/contribute to noted factory issues. All warranties for Voodoo Mods still apply.

Sorry no exceptions - Any and all units shipped in after 01-09-12 will be returned at sender's expense.

We recommend the Marshall JVM205 / JVM210. By comparison the JVM205/210 is more reliable, parts are readily available and we have several professional musicians touring/using these.

 

Marshall JCM900 4500 "Rock" Mods
Standard Mod™  $249.00  
Deluxe Mod™  $528.00 
Platinum Modified™  $852.00  FREE SHIPPING!
Platinum Modified™ 
$872.00  International Customers!

 

Mod Process & FAQ's
Packing & Shipping Info

 

 

 

 

 

"This is our original Mod for the JCM900 4500 Series - Great Rock tones!" 

 

  Standard Mod™  $249.00
Circuitry Modifications

Description / Specs:

  • All Modifications are exclusive to Voodoo Amps®  
  • This is the original Mod we designed for the JCM900 4500
  • Increased gain / distortion  
  • No matter how much gain you use you can still hear all the notes within the chords
  • When you turn the gain control to 10 - it's all useable
  • Increased sustain - Smoother & more liquid like
  • Faster attack - tracks every note you play immediately
  • Improved harmonic content
  • Harmonics will leap off from the fretboard with ease
  • Vibrato & bends feel smoother
  • You will not have to struggle or fight the amp
  • EQ sections are more active, flexible & musical  
  • Dramatically improved bottom end - Tight / responsive & fun to play on 
  • Over all frequency response is better balanced / more even sounding
  • Cranked tones at lower volumes
  • Will cut through & sit in the mix much better live as well as in the recording studio
  • Note: Channel 1 makes for a better crunch channel verses a clean channel 
  • Recommended Voodoo Add-On™ controls; Bottom, Push/Pull Bottom & Global
  • All features will function the same - Features are not removed nor disengaged 
  • We do not offer Modifications or upgrades to the fx-loop, switching circuitry or reverb   
  • All components used are high quality & are chosen for quality of tone, feel & reliability 
  • Please list "Rock Mod" in the notes section of the Mod-Form
  • Voodoo Mods™ retain your amps resale value verses decreasing it
  • Approximate turn-around time 5-7 days - rush service is available 

 

  Deluxe Mod™  $528.00
Output Transformer Upgrade to Standard Mod™

Description/Specs:

  • Includes Standard Mod™ (see above)
  • Incudes Upgraded Mercury Magnetics VA-4500-O Voodoo-Designed™ Output Transformer
  • $229.00 & $50.00 Installation fee (included)  
  • Vastly increased sustain - leads are much more liquid like & fluid
  • Effortless Pinch / artificial harmonics
  • Greatly improved articulation & definition
  • Increased / richer bass response
  • Increased even-order harmonics (IE: sounds much more musical)
  • Massive rhythm tones - when you hit a chord it's there immediately
  • Increased headroom (cleans stay cleaner & louder at gigging/stage volumes) 
  • Approximate turn-around time 5-7 days - rush service is available 
  • Transformer FAQ's

 

  Platinum Mod™  $852.00  FREE SHIPPING!
Power Transformer Upgrade to Deluxe Mod

  • Includes Deluxe Mod™
  • Includes Upgraded Mercury Magnetics VA-4500-P Voodoo-Designed™ Power Transformer
  • $249.00 & $75.00 Installation fee (included) 
  • 120V 60Hz Operation
  • Improved power regulation 
  • Reduced noise and hum
  • Improved feel & tone  - Smoother feel & easier to play 
  • A must for touring musicians, engineers and producers! 
  • Platinum Mod™ will give you the best tone, feel and performance 
  • Average turn-around time 5-7 days - rush service is available
  • Transformer FAQ's
  • Voodoo Amps® World AC Voltage Guide

 

  Platinum Mod™  $872.00  International Customers!
Power Transformer Upgrade to Deluxe Mod

  • No need for step-down transformers that can harm your amp!
  • Includes Deluxe Mod™
  • Includes Upgraded Mercury Magnetics VA-4500-PE Voodoo-Designed™ Power Transformer
  • $269.00 & $75.00 Installation fee (included)
  • Specify your voltage - 100V, 220V, 230V, 240V & More!
  • Improved power regulation
  • Reduced noise and hum
  • Improved feel & tone  - Smoother feel & easier to play 
  • A must for touring musicians, engineers and producers!
  • Platinum Mod™ will give you the best tone, feel and performance 
  • Average turn-around time 5-7 days - rush service is available
  • Save money! Buy from Ebay USA, have it shipped directly to us & we will ship it you!
  • Save money on shipping! We offer several shipping options, please Email us for an estimate!
  • Transformer FAQ's
  • Voodoo Amps® World AC Voltage Guide  

 

 Mod-Form  /  Mod Process & FAQ's  /  Packing & Shipping  /  Reviews  /  Contact

"Get inspired - upgrade your tone now!" 


 

 

Voodoo Amps® is the Leader in Tube Amp Mods & Upgrades

Pricing, features & specifications subject to change without notice

Like Us on Facebook

 "We have countless Mods that we have designed & will be adding them to the site daily!"

If you do not see your amp listed here please call (607-256-0465) or email us!  

 

  

 

 

Customer Feedback coming soon!

 

Copyright 2016 by Voodoo Amps