Thursday, 8 October 2015

Sagan Delay

Another new gigantic layout for you!
This is a Chris Carter's project from Madbean's forum.
( ).
He tried to create a PT2399-based delay that resembles the Roland Space Echo.
You can find all extra infos here:
Thanks to Savvas for verifying this monster!
Here is a video from Chris:

...and one from Savvas:


  1. 10 pots, 2 rotary switches, 3 toggles, this is insane man :-)

  2. oh my god that's insane man!

    but alex....
    i have an idea...
    you can add a 4,7k resistor and an LED+ wire somewhere at the middle left of the board,
    by doing this, you can't avoid an other cut.

    i know you don't have to, but please...
    it's worth it!!!
    this is gonna be the first "1 0 0 c u t s" b o a r d ! ! ! ! ! !

    tomorrow i'll go out and search those rot switches!
    great work buddy

    1. mmmmmmmmmmmm...edit....about the cuts....just saw Liquid Mercury "Tap Tempo"'re out of your will take a day to prepare the board...!!!

    2. Insane people do insane things to remain sane! :)
      Rounded the cuts number on Savvas request. :)

  3. Guess I'll purchase a small ammo box for the enclosure!lol ;)

  4. Wow! I am honored that my "little" circuit has gathered so much interest. This is insane; I am pretty sure you used some dark magic to get this layout.

  5. I think drawing a layout is easier than creating a new project. :)
    Thanks Chris for making it available to everybody!

    1. No problem. It was a blast making this happen. I had some PCBs for this but just sold the last of them. I will probably order more in the near future, if someone doesn't want to do this on vero.

    2. Hi Chris!
      Was this the correct schematic?

    3. Yes, the schematic in the build doc is the correct and final version. Technically, you can do without the second and third green LEDs, as well as the clamping diodes in the feedback loop.

    4. glad to see it come alive. I have been monitoring some of your posts. Are you happy with it? i built a multiplex and i like it a lot. Thanks for you hard work and contribution
      and all the work by all the contributors. Fantastis work getleman!!!

  6. hi alex.
    i just bought the switches and i set for a minute to take a look at the schem and the layout.
    i've found that from bass1 there is a 3k9 that goes to ground,but in your layout it goes to that correct?maybe i'm in the wrong schem cause there are some changed values too. for example treble2->1k5->33k on your layout, but at the schem i see1k5->3k6.also at tl072ic2_A from pin2 to pin 1 you have a 3k6 but at the schem there is a 4k7.
    i have the last verified schem by chris carter (purple letters)

    1. also there is a connection from delay1-1 to rot2-A.
      other than that i can't see anything wrong.

    2. Hi Savvas!
      I've used the schematics in the PDF folder:

    3. thanks man! so everything is ok.
      i just wanted to take a second look at this big baby before i start cutting and soldering.
      by tomorrow night we'll have news on this one!
      got to go to work now....

    4. Just asked Chris if that was the latest schematic.
      Added the Delay1-1->Rot2-A connection.
      Thanks for the heads up!

    5. Yeah, use the schematic in the build doc as a guide. Also mentioned in the doc is a suggestion to bypass the VPath send/return with the unused portion of the rotary switch; just add a jumper between pins 3&6 as well as 9&12.

  7. seven hours on this one...
    finished the board and the box drilling...
    there is no way to wire this just to test. so i'll take my chances to box it and then rock it...fingers crossed!
    wiring is pita...
    my huge box looks like a spaghetti colander...
    my brain hurts...
    haven't eaten anything...

  8. update.

    i've wired everything up and it doesn't work.
    i have absolute perfect voltages everywhere.
    the rotary switches must be wrong.
    i have a "delay like" (self)oscillation and feedback but signal cuts off.
    first of all i can't understand how the rotary switches are read on the schem.
    a picture of wiring and number lugs of the rotary switches would be really helpful.
    also at the notes of the document it says that we need a jumper at3&6 and 9&12.
    i'm really confused cause as i see at the schem, signal doesn't pass in some sets. for example at stops at lug5. or when rot1-a connects to lug3 what?input dies??
    do i need to have always a cable connected to sent and return?
    i'll upload photos at debugging section this afternoon
    but till then any help would be really appreciated...pleeeeeaseeee..

    1. to answer to my self, yes i need to have always a cable from sent to works now, but as i said, there are some sets, that signal cuts off. it works ONLY when i have sent-return connected.and it works as a reverb.(a really good one)

      no long time delay sounds...any ideas???

      now that is a strange and complicated effect...
      i'm totally lost here...15 hours in the last 2,5 days...

    2. Hi Savvas.
      I've added the rotary switches diagrams with the numbers and the 3-6 / 9-12 connections on the layout.
      Have you read the PDF?
      I haven't built it and I'm not really sure how it is supposed to work.
      Maybe Chris will be able to help you.

    3. hi Chris. first of all i want to thank you for this great effect.

      as you might have read, i'm on this layout that alex drew.
      i have some problems.
      some of them are described above.

      the real thing is that i don't get any delay, and delay pots don't do anything.
      level pots also don't mute this thing when they're all the way down. i don't know maybe this is what they should as other delays do too..
      i have oscillation with the feedback, mix seems to work too.

      my voltages are as they should.
      i probed my board and signal stops at the source of the it doesn't pass through pt2399s.i can hear the signal at the drain of the fet.
      i don't know if i get it right but i should hear something at the source. isn't it right?
      i get dry signal, but at pin16 of the first pt i get nothing and this goes on to the other too.

    4. i made a progress...
      see.... i had THE faulty 3p4t is an alpha one(!) and it's lugs are messed up!i only checked with the multimeter the 4p3t one and it was ok...but this one...the real lug1 is where lug2 usually is...and this goes on to the next till the final lug 12 which is where lug1 usually had to happen to me???and in this f%^&ing monster???god damn!!
      anyway...i've fixed that. i got better reaction but it is still working as a reverb. delay pots do almost nothing it's like they are fixed at minimum and only delay1 reacts somehow but only at the very same second i turn it up or least i now have signal at the source and into the delay path.but...

      help still needed!

      sorry if i'm buzzing you with this one with 2 posts everyday...
      hope i'll fix it soon...cheers.

  9. Verified...
    5 days troubleshooting...
    it just needs bc550 in the other way.
    if you read the pdf there is a note about that, that i thought it was a problem in how Chris printed his pcb.
    now i got it working just perfect.
    all pots act as they should.
    thanks Chris for your help.

    also thanks to Alex.
    your layout is perfect as always man.
    i just had a bad luck on that.
    especially with that "faulty" rotary i got...

    tag it!

    1. Cool Savvas!
      I had a look at your pictures and everything seemed ok.
      Couldn't understand what was wrong with it.
      I was gonna build one as soon as I could just to test it.
      I'm glad you've managed to fix it!
      Are the BC550 oriented correctly on the layout?

    2. Almost forgot... how does it sound?

    3. Congrats on the great layout and a successful build! I gotta finish my pcb build of this circuit now.

  10. demo and a "guide" here:

  11. For those of you would rather have this circuit on a PCB, I have set up a group buy on the Madbean forum.

    1. Hi Carter, do you know were I can find the pcb ?

    2. Simon I have a pcb to sell

    3. Hi Daniel, I'm very interested, how I can contact you ?

  12. Question, On your layouts what is the difference between the yellow and brown capacitors?

    1. I believe I figured it out, yellow is box and brown is non box Polyester caps.

    2. Hi Dave.
      I just use the brown one cause it's a two rows space and you wouldn't be able to read the cap's value if you used a box cap in the drawing.
      You can use any type of capacitors.

  13. The tallest piece of vero I can find locally is 30 rows high, so 3 short. Any ideas for a work around?

    1. hey man. there are many options depending on where you live in the world. i'm in the us and there's a company in canada, which has all different sizes of vero. they're not the cheapest, but great quality. you can also look at the boards available at tayda, as they now have larger vero that's the same as their smaller boards and is cheap and good quality. you can also look on amazon, i know sells on amazon as well.

  14. Savvas, do you think you could explain the rotary switches in a little better detail? I read Carters build and looked at all the pics, and so far it looks like one of them let's you select how many of the delays are on, but it was like '0, 1+2, 1+3, 1+2+3' so I'm kind of wondering what the deal is there. The other thing I'm wondering about is the MOD in feature, could the LFO daughter board from the Deprofundis be used? I have been looking at multi-delay units for a while and this looks like a great project.

  15. Hello,

    Can anyone tell me where goes the 2 negative LEDS on the left of the board (between ROT1-B & LEVEL2-3) : Tails sw LED - & LED - ??

    the doc here explain how to solder "the DPDT Tails switch" but there's only 1 LED...

    Thanx for all !

    1. A few years late but any update on these LEDs? I’m about to start but getting my ducks in a row.

    2. This comment has been removed by the author.

  16. Can someone can please help regarding the Tails switch? it has 6 lugs but only the first 3 are mention in the layout. how to connect the other 3 ?

  17. Is the bc550 in the vero layout is the right direction ? I get a delay only for a second when changing the delay pots but not more then that

    1. The layout matches the BC550C's I have

  18. I had to flip my BC550s around as well so they are top to bottom EBC.. opposite of the schematic. Verified with an atlas dc55.. mode 1 works, but modes 2-4 all only have one repeat so I'll be troubleshooting that.

  19. A few other observations, definitely use the closed body 3P4T rotary, it makes life way easier. The feedback pot is shown as A500k on the layout but it's B50k in the schematic, I used a B100k as it seemed to have runaway too easily. There is a 100k going in to pin 16 of 2399 number 2, but the other stages and every other delay I've looked at shows a 10k for the pin 15 and 16 resistors.. thought this might be a typo.

    And then finally, yeah the BC550s had to be flipped which doesn't make any sense to me at all, but as Savaas said above, only reverb super short delay with them as shown in the schematic.