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Wednesday, April 1, 2020

EQD The Warden

This one was due for a revision/redo. Optical compression with all the knobs from our favorite pedal slingers in Akron. Will fit nicely in a 125B with top mounted jacks.



38 comments:

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    1. Yes, a 500k dark. Specifically a GL5516

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    2. Can't wait to give it a try! Thanks a lot for keeping us busy during this strange time!

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  2. Not much parts... I think is posible to relayout for fit in 1590B..

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    1. Do one and post a link here, might be helpful to some people.

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  3. I only have some fakes mpsa18 with hfe of 350. 3 of the se would work in the circuit?

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  4. hey, what's the difference between 5516, 5528, 5537 and 5549 LDR? thanks ��

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    1. It's a part number. The difference is the amount of dark resistance

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    2. they have different resistance in the dark

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    3. Jandalesands, from my notes the different LDR dark resistance

      5516 = 500K
      5528 = 1M
      5537-1 = 2M
      5537-2 = 3M
      5549 = 10M

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  5. Replies
    1. Probably. Just double check what pins need to be grounded for the 7660.

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    2. I used a ICL7660S in my build with no issues.

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    3. Make sure it is 7660S, 7660 will produce 10kHz hiss. Same goes for cheap fake 1044s from shady corners of Internetz beyond Great Wall.

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  6. Hello. This layout has been verified. As to transistors, I tried MPSA18/5089s, MPSA18/5088s and all 5088s. All work.

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  7. I only have 1M dark resistance ldr and I can't find 500k nearby. Do you think putting 500k parallel resistor would make it work? Or should I try it with 1M LDR?

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    1. I would experiment with both options and see which works best.

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    2. One last question, I assume OPA2134 is connected to 18V, right? My problem is that I can't find it neither and I was thinking about putting TL072, but it says that "it is not advisable to run on 18V". What are substitutes od hi quality op amp that can handle this voltage?

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    3. A TL072 should be fine at 18v. I believe the max voltage for that chip is 36v (or +/-18).

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    4. Your TL072 is a high quality op amp that can fit spot on. Tried this setup: tl072 with BC550s inplace of mpsa18 and works great.

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    5. Also, my LDR goes to 12M after I placed it in heat shrink tube with the LED. Pedal works great. Perhaps would need to compare with different LDR once I grab one to see if it makes big difference.

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  8. Does anybody know how to add sidechain input to this one?

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  9. Hi,
    How would one do to add a gain reduction indocator led?
    Thank you

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    1. I added switchable LED in series with vactrol's LED side. Switching it on has an effect of increasing attack and lowering ratio (blend). Compression only kicks in at later stage. Could not figure how to do that in a transparent way.

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    2. Thank you. I still hope we could find a solution to have a led indicator work without affecting the sound :)

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  10. Hi!! Is it a problem if I use some 16V electrolytic capacitors ???

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    1. Theoretically it shouldn't, but I've seen 16v caps blow on a 9v supply. I usually go 35-50v personally.

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  11. What kind of caps are the 1uF caps at T8 and F21? They don't look like ceramic, film, or electrolytics.

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    1. Box film caps. I get them from Tayda

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    2. I had just bought some, and the circuit sounds good. It's a nicely subtle effect using MPSA18 and 5088s. I may get some 5089s to see how it changes the behavior.
      I've built the Fat Fuzz Factory and Morning Glory v3 as well from your designs and they all sound good. Thanks for everything!

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  12. What are the additional Ground slots for, down near Out and up near 9v?

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  13. This comment has been removed by the author.

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  14. I'm trying to fit this in 21*20. I want to make diagram of yours but can I have your diagrams for capacitors and else?

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  15. Hello, I wanted to ask you what type of capacitors are the green ones, the yellow ones and the gray ones, which appear in the diagram. Thank you so much.

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