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This page has several variations of the Tone Bender Mark II Professional. If you want to simply build a standard Tone Bender, don't be overwhelmed by the many variations, just build the first one listed (PNP Positive ground) which is the standard unit.

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Here are the several variations of the Tone Bender Mark II Professional. Options are to build it with PNP or NPN germanium transistors or even with NPN silicon transistors. There's also an option to build the PNP with Negative ground wiring. The Negative ground is more common in stompboxes and makes it easy to hook up the Tone Bender to a common power supply. There is absolutely no tonal difference between the PNP positive ground and the PNP negative ground. Whichever version you chose to build, they all use the same Printed Circuit Board layout.

Please Note: For a simple project, I recommend the "PNP Positive Ground" version. Get your transistor set from Small Bear Electronics LLC and use the resistor values that he sends with the transistors. His resistor designations (R2, etc) match the designations on these projects. If you have a common power supply to power your pedals, the PNP negative ground version and the NPN versions will work with your other pedals on a common power supply.

Please Note also: When I designed the board I made a decision to make it so that if you want to build the silicon transistor version, you need to cut 3 traces. I didn't want to make it so the germanium versions had three extra jumpers, so the cuts must be made for the silicon version. A diagram is provided for board prep for that version below.

Common Files For All Versions

• Tone Bender Mark II Ready-For-Transfer Printed Circuit Board Layout

PNP Transistor, Negative Ground Version

• Tone Bender Mark II Bill of Materials
• Tone Bender Mark II Schematic
• Tone Bender Mark II Parts Layout and Wiring Diagram

PNP Transistor, Positive Ground Version

• Tone Bender Mark II Bill of Materials
• Tone Bender Mark II Schematic
• Tone Bender Mark II Parts Layout and Wiring Diagram

NPN Germanium Transistor Version

• Tone Bender Mark II Bill of Materials
• Tone Bender Mark II Schematic
• Tone Bender Mark II Parts Layout and Wiring Diagram

NPN Silicon Transistor Version

• Tone Bender Mark II Bill of Materials
• Tone Bender Mark II Silicon Version Board Preparation Diagram
• Tone Bender Mark II Schematic
• Tone Bender Mark II Parts Layout and Wiring Diagram

Here is more information and projects links related to the Tone Bender Mark II Professional:

• Order Tone Bender Mark II Professional Parts - from Small Bear Electronics LLC Get everything you need, including a selected matched set of transistors for the Tone Bender Mark II Professional!