Wednesday, 2 September 2020

Dinosaural Tube Bender

In October 2003, Dan Coggins (formerly of Lovetone) released his first commercial pedal under the Dinosaural brand, called the Tube Bender. His design goal was to make something that was sort of a tonal hybrid of the Tone Bender and Tube Screamer, hence the name. And honestly, having listened to it, I’m not sure there’s a better way to describe it. He only made around 140 of them between 2003 and 2007, but many of them were snatched up by musicians and producers in the UK. So while they’re exceedingly rare, you’ve most likely heard it.

 

I added a mod from the AION Wyvern Silicon Drive of  a second position to the Tone Shift switch that’s in-between the flat and scoop modes. I've included the hfe readings from an original pedal as per Aion's trace, so you can try different transistors with similar gains. 

 

It's so rare I couldn't find a demo of it, but I think you get the gist of what it should sound like. 

 



23 comments:

  1. Seems to be missing drive 2 to Q3 base

    https://vero-p2p.blogspot.com

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    1. And I should mention that I’ve built one (different layout). I like it - it has a few very usable sounds, from super clean through to a pretty heavy overdrive. It’s not a one trick pony that’s for sure.

      I had built one using the old schem floating around, and it kind of sucked. This doesn’t suck...

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  2. And tone 2 goes to level 3, level 1 to ground (could be connected to row C), and level 2 to output

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    1. Thanks for point that out. Completely forgot to include those in the notes. Can’t belief I forgot. Will update as soon as I can.

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  3. Updated the notes and moved some things around.

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    1. yep. made the change. cheers for the catch

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  5. Now there is no bias connection to Q4 base. The 10K in column 16 goes to Q4-E, should be Q4-B. It's a great sounding circuit, I breadboarded it. Just as important as HFE-matching Q3 & Q4 is Vbe matching them. I used 2N5232A for Q3 & Q4 (had 'em laying around). The HFE on those two is 280. The lower HFE makes the bias sensitive to the DRIVE setting, which has the advantage of introducing some even-order harmonics at high DRIVE settings.

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  6. Flip q2 around, take out the jumper to the right of q1, move the 1.2k from q1-c to the new q2-e, move i16 (10k) up to h16 and move the cut from g15 to g17, and then move the i13 (47n) down to k13 and then it works and sounds great.

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    1. thanks for those catches. you still want the to leave the cut in place at g15, g17 has a link. you also want to keep that link to the right of Q1, as it connects Q1 C and Q2 B to Q2 E without having a standing resistor. layout has been updated.

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    2. The 10k connects to the base of q4 and you still have it connecting to q3.

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  7. This looks great thanks for posting

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  8. Hi -- compared layout to schematic for Aion Wyvern. The cut on H15 should be moved to H17 so the 10K resistor connects to the base of the transistor Q4 on column 12 instead of to the transistor Q3 on column 19.

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  9. Just looked at this and perhaps I'm not electronically literate enough to understand, but from what I saw on the Aion site on the "Tracing Photos" (https://aionelectronics.com/blog/tracing-journal-dinosaural-tube-bender/) is five transistors, two of which are PNP. Their documentation for the "Wyvern", as they call it, lists four BC549C's and one BC307B, yet the schematic and subsequently, the board they are selling, only have four transistors being used. Like I said, I'm no electronics wizard, so maybe I'm missing something. Can someone please clarify this? Thanks!

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    1. The 5th transistor in the original was part of the bypass switching. Its similar to the millennium bypass, which lets you use a DPDT switch and have an LED. I did not include It as you can just use true bypass switch wiring with a 3PDT switch.

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    2. Thanks for clearing that up for me. That makes perfect sense.

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  10. Zach, Alex, have you ever hear about this project https://www.deeptronic.com/electronic-circuit-design/diy-reverb-pedal-circuit-from-spring-to-room-like-reverb-using-multiple-pt2399-ic-chips/
    Seems to be very interesting...

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  11. This is a really great sounding pedal with a surprising range to it. Really, really, nice design from Coggins and a big thanks to Aion/tagboard for the trace and layout.

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  12. Is this considered verified yet? There seems to be some successful builds.

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  13. I built this layout with BC549Cs from PedalHacker and a 2N3096 in Q2, sounds fantastic. Like a tonebender with a nice tone control.

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