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Sisyphus Strut - Echo Base with effects loops

Started by mcasemo, December 29, 2014, 07:04:45 PM

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mcasemo

Not a madbean board, but thought I'd share.  I almost gave up on this one, whenever I go off the normal build instructions and try to add features, it gets ugly.  But I finally got this one working with lots of help from slacker and others on diystompboxes.  This is the echo base delay with a blend mod (dry/wet), dub madness switch, modulation shape pot, and a switchable effects loop.  One side of the loop/switch sends the delays through an external pedal once, the other side keeps sending the repeats.  In both cases, the clean is not effected, and the first repeat goes through the loop.  I had to learn about buffers and such for that.

My brother is an English major and I grew up hearing about Camus and the Myth of Sisyphus, and i guess it stuck.  Sisyphus has to push the rock up the mountain, then it falls down the other side, and he has to keep doing this for eternity.  Camus said we must imagine Sisyphus happy in the Myth of Sisyphus.  So I made Sisyphus doing the only fun thing i could think of that involves moving heavy objects, bowling.  The "Strut" is a homage to The Meter's song Cissy Strut, which certainly has no delay effects, but who cares.  Clear water slide decal on bare aluminum. 

Wiring is pretty bad, there were a lot of redo's.  I had all the wires at good lengths, but just gave up trying to make it clean when i had trouble making the loops work.  If anyone is interested, i can attach my cryptic powerpoint schematic.




bcalla

Great use of an octagonal enclosure!   And excellent decal work.  I have one of those boards in my backlog pile.  Are all those mods in the Echobase thread on DIYSB?  They sound pretty cool.

mcasemo

#2
The dub madness, LFO shape mods are in the board documentation.  The wet/dry mix and effects loops stuff I searched for on the forums and ultimately slacker drew up what he thought would work for me in a PM.

Omit Level pot on board, put a pot in place of the 10k resistor as indicated to change the delay level.  I used 10K pot.

Omit 10K resistor as indicated and wire up mix pot, I used b50K pot I think, with the added 220n cap.

The 20K resistor under the feedback pot can be increased so that the feedback does not self oscillate too early.

I wired up a daughter board for the buffer needed for the loop that effects the delay each time.  Omit the 4n7 cap as indicated, it get's put on the board after the return.  Below are the schematics for the 4pdt switch and routings to the send and return jacks.  Kinda sloppy, but i think this is the final layout i got working.  Ignore the bright green marks on the board




Hogharry

I just love the graphics and the octagonal enclosure works really well. Clean is nice but the important thing is that you made it do what you wanted it to do. Well done!
...and then of course I've got this terrible pain in all the diodes down my left hand side...

PhiloB

Man that's fantastic!!  Looks great too.  Way to go. 
Btw, love Cissy Strut. 


Sent from my iPhone using Tapatalk

bcalla

Thanks for sharing your mods.  They're going in my build notes.

Leevibe

Really cool! I agree that using an octagon for a pedal with an fx loop makes sense. Congrats on getting your mod ideas to work too. I love it.

pickdropper

Very nice!

I assume with the theme that there was a lot of troubleshooting involved.   ;D

Your build reminds me of an old Onion article from a while back:

http://www.theonion.com/articles/getting-mom-onto-internet-a-sisyphean-ordeal,1404/
Function f(x)
Follow me on Instagram as pickdropper

mcasemo

Haha!  Sisyphean ordeal!  I had not thought of applying it to the effort, so funny.

mcasemo

Update on this one in case anyone is making these mods.   I'm having an issue with the feedback/oscillating.  The issue is that when i disengage it with tails on, it will start oscillating sooner than it would while engaged.  it has a greater tendency to self oscillate when disengaged.  For instance, if i have a repeat going that is dying out, hit the bypass, then it start growing.  Or it is quiet, but feedback turned up reasonably, switch it off, then the oscillations start coming.

Ian (slacker) took a look and suggested that it may be  "the loading on the input of the buffer changes depending on the state of the CD4066 switch, when it's open (the delay is on) it reduces the volume, when you bypass the effect and the switch closes the resistance seen by the buffer goes up increasing the volume."

He drew up an op amp mixer as an alternative to the transistor buffer.  If I get it working (on the back burner now), i'll post the changes.

Just wanted to let anyone know these mods might not be up to stuff yet.

cheers,
mark