Wednesday, 11 July 2018

Ethos TWE-1

Info:
"Inspired by the Trainwreck Express amplifier (built by the late Ken Fischer), the TWE-1 is solid-state pedal designed to emulate the touch-responsiveness and clean-to-overdriven range you get from a high-grade tube amp. Along with Volume, Hi Cut, and Gain controls, the pedal has 3-position Cab switch (4x12, 2x12, off), a Presence switch that provides three levels of high-frequency boost (post OD), a Voice switch (Traditional and Modern British), and a bypassable Brite switch that provides two levels of high-frequency boost (pre OD).
The TWE-1 with its Gain at noon or higher responded in an amp-like way to changes in guitar volume and picking strength, delivering everything from gritty cleans to richly saturated distortion textures. Thanks to its strong output, the TWE-1 is suitable for clean boosting too. All good stuff, but the standout feature of the TWE-1 is its powerful tone-shaping ability. The Hi-Cut knob attenuates treble when turned clockwise, and the Brite switch makes it easy to get the appropriate sparkle with humbuckers or single-coils. The Cab switch beefs up the low-end significantly in the 4x12 position (I felt the 2x12 setting sounded best with my Deluxe), and the Voice switch lets you choose between a thicker tone in the “M” position or one with more upper-midrange emphasis in the “T” setting. The Presence switch set to Hi restores shimmer when the Hi Cut control is turned up (a cool sound in itself), and between all of these functions, the TWE-1 certainly answers the needs of players who want a compact OD pedal with exceptional sound and flexibility."
The layout should fit in a 125B size box.
You can find Bugg's schematic and easier-to-build pcb on his website here.
This is a buffered effect. Follow the layout to connect the footswitch.



14 comments:

  1. Check out Brett Kingmans video of this also. Killer!!! Im working on Pedalpcb's board now.

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  2. Really cool indeed, Alex. I was almost about to request this one from you hehe! I just need to find where to get those 1v8 zeners...

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    1. It could be the 1N4678 diode: 1.8v zener diode. Pretty rare, indeed. I think someone of us should find some replacement.

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    2. why not just take 3 1N4148 in serial. They forward around 0,6 V each.

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    3. Three 1N4148 or a LED, a green diffused one, I guess it's ok. In any case we should get about 1.8v forward voltage.

      I just concern about a little detail in case we have to use a LED. I found this note about it on wikipedia:
      https://en.wikipedia.org/wiki/LED_circuit
      "but voltage drop normally rises as the light frequency increases".

      Maybe this is the reason why MAO suggested to reverse the orientation.

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  3. Looking at the schematic, I think LEDs with a 1.8v forward voltage reading would accomplish the same thing. I'd probably reverse their direction though.

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  4. https://www.mouser.com/ProductDetail/Central-Semiconductor/1N4678-BK?qs=sGAEpiMZZMtQ8nqTKtFS%2fNTW9pm8IdF6NwWdEkMc7Gx7JO0zV3Ng4Q%3d%3d

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  5. I did a search and I think it's not possible to get those 1N4678 zener here in europe. Mouser has a website even in german and a contact in munich, but there are about 20 Euros for shipping ...

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  6. Nice blog about the guitar FX. If you need custom picks please let me know. www.custompicks.com

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  7. Replies
    1. That was a mistake. Changed this instead of the GTC Bloody Finger.

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  8. Hey Alex, what is your idea about this zener diode?

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  9. The reverse voltage drop of the zener is 1.8V but the forward drop is 0.7V like a normal diode. Therefore the drop across the back-to-back zeners is around 2.5V in both directions. However, low-voltage zeners such as these have a soft knee, i.e. they don't turn on abruptly. This should have a soft clipping effect, probably why they were chosen.

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