Adcom LX Series Modifications


Modification Strategy: Our venerable LX mod for your Adcom amplifier has changes in feedback circuitry which improves bandwidth, dynamic range and bass solidity/power. The bias circuit uses a new and better bypass capacitor. Input and output filters are improved with far better parts. Some critical resistors are upgraded. Each small-value (p high frequency stabilizing capacitor is optimized for audio quality.  Each power supply capacitor has an added bypass capacitor. Elite and higher models have superb power rectifiers in the main power supply. We use the finest soft-recovery diodes that are superior in naturalness and dynamics. 


LX Sound: is much more natural, sweet and liquid. Soundstage is much more open. Imaging from top to bottom is more predictable, i.e. instruments come from stage locations that seem more accurately positioned. Gone is the brightness, etched quality and bass inaccuracies. Perceived dynamic range soars!


LX Elite Sound: More refined/defined with solid bass extension and silky extended high-end detail, a definite improvement in resolution and definition. The mids have superior timbre, texture, clarity and musical naturalness. Highs are more natural and clear.


>>>We no longer support all Adcom power amps, GFA-5800/5802 plus some others and multi-channel amps are not serviced.<<<



Options? Visit these pages - Amp Options  including maintenance suggestions, power supplies PS-200

See our "Connector" page for RCA jacks, binding posts, IEC sockets!



LX Mod

LX mods are for classic stereo or mono Adcom amps, including all “535”, “545”, "555", "585", “565", 5500 etc. 


Features of the LX Mod*



$399 installed for early Adcom stereo and GFA-5500 amps

GFA-565 LX mod is $599/mono pr

*Will vary with different Adcom models



LX Elite Mod

The LX Elite mod includes all the features of the LX Mod Plus*:



LX Elite Mod $629 installed for all early model Adcom stereo amps, other items listed below

GFA-5500 $699

GFA-565 $899/pr

*Will vary with different Adcom models



LX Ultra Mod - Adcom GFA-5500*

The LX Ultra mod has all the features of the LX Elite mod and then:



???What is our reasoning for this multi-step package? If you order the Audio Grade ‘front-end power supply, which is popular, and /or Ixys rectifier upgrade for the output power supply, also popular, these requires some disassembly that is needed to also replace an IEC socket and binding posts. The package saves some money due to overlapping labor steps.                


GFA-5500 LX Ultra mod $1099 installed

*Call for availability, some parts hard to source

#For power supply board mounted atop the large filter cans.





Adcom Amplifier Modifications