2205 "RICH MOD" Post Master Volume!

CAUTION: TUBE AMPLIFIERS CONTAIN LETHAL VOLTAGES
EVEN WHEN UNPLUGGED


Table of Contents

READ FIRST-DANGER HIGH VOLTAGE

Rich Mod Over View

Replace Presence Pot

Hook Up Points

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SAFETY AND FILTER CAPACITORS
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!!CAUTION!!
HIGH VOLTAGES EVEN IF UNPLUGGED!
TUBE / VALVE AMPS CAN STORE VERY LARGE
VOLTAGES! THESE VOLTAGES CAN KILL YOU!


You have to understand how to safely work inside the chassis of a tube amp. Just reading this is not enough, but here are a few tips: Never work on a amplifier that is plugged into the wall socket, always unplug it first! Stand on a rubber mat of some sort and don't work bare foot, under the influence of alcohol or any other drug, legal or not for that matter. Here is another good tip: Only probe an amp with you're right hand and with you're left hand by you're side. So if you do happen to take a high voltage shock, the the voltage will not go across you're chest!

High Voltage is stored in the electrolitic capacitors and they need to be discharged!That's what I'm doing in this pic. These are those large round can's and there usually blue or black. The discharge tool is made of 600 Volt wire with a 3-5 watt resistor of 500 to 1000 ohms. Basically you clip one side to ground then clip the other end to the Pos + side of the capacitor. Check with you're multimeter set to 600 DC volt setting and make sure the voltage has been discharged.

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FX-LOOP KIT
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The Rich Mod


Its a form of the old Post Phase Inverter Master Volume.

Note: This has been tested and Its awsome in the 2205!

If you don't want to drill a hole then do as I did and remove the presence control.

Kit will come with all parts needed.

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Replace Presence Pot
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Put a resistor to fix the presence level.


This is what I did.

Note: This has been tested and Its awsome in the 2205!

With the pesence control pot removed, and the resistor in place. Its time for the B500k
dual ganged PPIV Master Volume pot. presence control is now fixed.

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Hook Up Points
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You have to remove two stock capcitors first!


I used cheap 20 gauge solid core wire, a alpha B500k dual gang pot, and
.047uf Orange Drops. You can see where to connect everything its very easy!

Note: This has been tested and Its awsome in the 2205!

The solid core wire was great at keeping the wires spread a part from other components.

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Copyright © 2005-2006 by Robert Souza. All rights reserved.