Monday, 28 January 2013

Catalinbread SCOD

On hold for now, pending verified schematic.




27 comments:

  1. Whelp, there goes my afternoon....

    Thanks Miro!

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  2. Mirosol

    Tayda has this: CD4007 4007 DUAL COMPLEMENTARY INVERTER IC CMOS.

    Doesn't indicate "ube" in the description. Will that work or do I need to find the part with "ube"?

    Thanks

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    Replies
    1. UBE means unbuffered, and I'm pretty sure the Tayda one is unbuffered

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    2. Ok. I found the part with the UBE suffix at Mouser too. Maybe I'll pick up some from both.

      Thanks

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  3. This is verified? Considering the 5% to 10% tolerances on most parts, do you think that using 47nf instead of the 50nf caps would affect the sonic footprint much?Having trouble finding the 50nf cap value....

    Thanks

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    Replies
    1. I suspect most people would use 47n caps here and there'd be no problem doing so.

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    2. Cool. I always measure my caps and resistors before installing and for some reason the caps usually seem to measure on the + side anyway. I ordered the ICs last night so I should have this up and running by the weekend.

      Thanks Mark

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  4. When I built this pedal it did not sound right and I did not like it and put it aside. Weeks later I decided to have a look at a Schematic by Madbean@freestompboxes.com. All looked the same and OK except the 1M resistor at the input to ground. I did not expect a change but I decided to test this pedal by removing this 1M resistor and I was surprised by how much better this pedal sounded. Now I am actually using it and enjoying it. Can someone explain why this is so electronically??? And is this 1M resistor suppose to be there in the schematic used by Mirosol.

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    Replies
    1. That 1M is just a pulldown resistor to prevent popping when you turn the effect on and off. It doesn't affect the tone as far as I know.

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    2. No it should not have any effect on the sound. It's there to prevent popping noises from the switch. And no the schematic doesn't have one. This is one of those situations where i basically have two choices; either add it straight away as it is electronics standard to have one, even if the schematic doesn't have it specified - or answer three or four questions about how to eliminate the popping from switching. I've never heard before that adding or removing a pulldown resistor would affect the sound of the board...
      +m

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  5. I'll have mine finished in the next couple of days. Almost there. I'll report back with results. I am subbing 47nf caps for the 50nf as they were very difficult to find at that value. Hopefully that won't make too much of a difference in sound.

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  6. Finished this build today. Have to say I'm pretty disappointed. On all the demos I've seen, there is a fairly high amount of distortion even at the lowest gain setting. On mine, it goes from almost no gain at the lowest setting up through a sort of heavy overdrive sound until you get the gain maxed out. Then it sounds pretty distorted, but more like the lower settings on the demos. Kinda muffled and bassy sounding for most of the sweep of the contour control until you get it to the far right side of the sweep. I don't think I made any mistakes in the build - all the controls work as they seem to be designed ( and all components measured before soldering in ). It just doesn't sound that much like the original.

    Now, that being said, I did sub 47n for all the 50n caps. And I subbed 4.7n for the 5 n caps. Maybe all those cumulatively add up to the suck that my pedal is delivering. Maybe a build with all those exactly as called for will make a difference.

    John Rep - was the issue you had similar to what I have described before you removed the 1M pulldown resistor? Heck - I guess I'll go clip it when I have time and see what the difference is. As is, I'll be recycling this enclosure.

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    Replies
    1. Tinkercreak- I may have had a poor join near the 1M pulldown resistor that I may have actually fixed accidentally when I removed that 1M pulldown resistor. I socketed this resistor and tested it in and out and it might be my imagination but with it in although very subtle I think you get slightly more treble tone although as Mirosol & Geiri pointed out it should not make any difference at all and is only used for popping issues. Other Catalinbread pedals I have built on this site which I have been happy with are DLS (DLS MKIII has just been posted on the site) , Formula 5, WIIO , CB30, My Galileo built was a disappointment but I will have to have another look at it. Dont be dishearted There are actually more Great pedals here on Marks sites then Dudes. Have Fun.

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  7. Just thought I'd add, The amount of distortion you get will vary with the type of Guitar pickups and Amps you play on. The best distortion I actually get at Bedroom Levels is through a Noisy Cricket MkII Amp I built from this site. It is great I reckon for replicating what pedals are capable but can only be used at low volume. Things change and the pedals react differently on the Bigger Fender & Marshall etc Amps.

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    Replies
    1. Thanks for the reply Jon. I actually went over and read the full post at FSB. They actually said almost the same same thing as I experienced with my build. It's not a bad sound - just not exactly what I had expected. I do play Strats so I know I'm going to be getting a little less output from my single coils ( or a lot less if it's my Vintage style Fralins - but they sound sooo good clean! ).

      Don't worry man - I'm not disheartened - I've built about 40 pedals from here and about 70 or so overall including Sabro's site. I've had too many great pedals ( thanks ALWAYS to Mark and Mirosol !!) to be too disappointed about a couple of duds here and there ( you gotta build the Magna Vibe - that one was crazy better than I expected ). Plus I learn something new from each build.

      I believe it's on to the Frantone Cream Puff next....

      Thanks

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  8. There's different types of 9.1V zeners.(1N5346B, ZMM00, BZX83V00, BZX85V00, KS191A, KS191C, KS191T, ZY). Any difference which one I use?

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    1. Doesn't matter. There may be differences in voltage rating as in 100V vs. 1000V and how much power they can take, but none of those matter in this application. Use what you have.
      +m

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  9. I'm wondering if the verified tag should be removed from this layout. My build has the same problems that other people have noted - lots of volume, but very little gain compared to an original or any of the demos I've heard. Thoughts? Has anyone had a successful build that Monica an original unit?

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    Replies
    1. Should say mimics, not Monica. Thanks autotype!

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    2. On FSB, R Customs says the schematic is verified and both, R Customs and Madbean schematics are the same. Layout matches the available schematics. People on FSB have had same issues as you with their builds, no matter if they were from mine or Mictester's layout, or from R Customs PCB. On the other hand, Mictester has slight mod that sets the gate bias voltage for the MOSFETs. You could try taking the 62k out and replacing it with a 100k trimmer to see if that sorts it. You did use 62k resistor? If that doesn't sort it, i'm leaning towards erroneous schematic.
      +m

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    3. Thanks for the quick response. I'll try out a 100k trimmer and see what happens. Stay tuned! Also Merry Christmas!

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  10. 100k trimmer installed - very little change. I'm leaning towards erroneous schematic as well. Im going to dig around some more. I know this pedal is essentially a nut cruncher sandwiched between two MOSFET boosters. If you have any ideas I'm all ears. Thanks!

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    Replies
    1. Removing the tag and putting it on hold. No ideas at the moment...
      +m

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  11. Hi guys, i found a perf layout... maybe it can help http://blogs.yahoo.co.jp/mitani518/folder/1181531.html?p=2

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  12. following the link above try 1M7 in place of 1M, at IC right

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