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Improved Tonmann Layout with on-board Modifications and Wiring Options!

Board Dimensions (W x H) 1.53” x 1.83” ca. 38.7mm x 46.4mm

1. A flashing LED that shows the speed of the LFO has been added. Internal or new External mounted for conveniently knowing the speed before you switch it on.

2. A “Kill Switch” (SW 1) has been added. Closing the switch shorts the LFO leaving you with the excellent sounding buffer for improved Guitar Tone without the Tremolo effect!

3. If a Rate LED  is not used you must Jumper the 2 NON-White pads of three available LED Pads or the circuit will not work.


EA Tremolo Audio Demo


EA Tremolo Build Instructions

Check the Forum for answers to many questions before posting a troubleshoot thread.

Do not miss the Easy Pedal Wiring Guide.

Namely the expansive Tips, Tricks and Tutorials section and the consolidated Crash Course Guide.

Depth Mod adjustments courtesy of Tonmann:

As the circuit stands the "50% mix" is about right, for more depth you would need to change the values of two resistors (changing the Depth pot won't help).

Rather than the long techie explanation, here's the short version:

First is a point about sockets - circuit boards are not designed for constant soldering and desoldering so if you are trying different values for a component it is advisable to install sockets, enough said.


Change the value of R9 to 4k7.


Change the value of R6 to 560k.  Measure the bias voltage on the collector of Q2, you are looking for a voltage of not more than 6.5V - 7V or less (less is better).  If you don't have a 560k resistor on hand you can use a lower value resistor (lower value means higher bias voltage) anything above 270k should be OK.  If you output  signal shows signs of clipping distortion you will need to increase R6 to reduce the bias voltage on the collector of Q2.


That's it.


For troubleshooting purposes here is an interesting thread should you run into a problem.

Thanks to Tonmann!

Courtesy of Tonmann:

November 2, 2012 at 11:48 AM Flag Quote & Reply

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Posts: 8793

Check out this EA Tremelo Build with another unique way of making it their own!

EA Tremelo Build Courtesy of Krizroring

May 27, 2015 at 10:14 PM Flag Quote & Reply

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