TS7 Tube Screamer to TS808 Specs
Excerpted from Robert Keeley's TS-7 Tone Lok Mods page. with minor additions by Ashley.

There are several interesting things about the TS7. First of all the circuit is nearly identical to the TS9. Why do I say nearly? The circuit has a Hot mode and the parts are 1/8 watt in general instead of the 1/4 watt used in the TS9. There should be little argument that the wattage of the resistor affects tone. The Hot mode switched can be set to the TS9 mode and *puff* you have a TS9. At about 1/2 the cost! Here are some other interesting things. The new TS7 comes with the re-issue JRC4558D chip. So if someone is charging you to install a JRC4558D chip in the pedal BEWARE!!!!



  1. PARTS: You'll need a 10kohm resistor, a 100 ohm resistor, a soldering iron, and some solder.
  1. Open your pedal by taking out the four screws on the bottom. Remove the bottom cover and put it off to one side. Be careful not to lose the spring that will fall out of the switch end of the pedal.
  1. Remove the two screws holding the large circuit board to the pedal chassis.
  1. Carefully lift the large circuit board out of the chassis. The power adapter end will be connected to another board underneath. Pull gently to 'unplug' the large board from the smaller one.
  1. Locate the small circuit board next to the output jack and remove the two screws holding it to the pedal chassis. The output jack is soldered to this board so when you pull it out you will also have the jack out of the chassis.
  1. Replace the resistor labled R58 (the blue circle) with your 10kohm resistor and replace the resistor labled R55 (the yellow circle) with your 100 ohm resistor.

    The green arrow points to the JRC4558D chip mentioned earlier.
  1. That's it. Screw everything back together and you've got a modern TS808 Tube Screamer.


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