Thursday, 25 April 2013

Frantone Cream Puff

Original unit has relay based switching and 1000µ filter cap. This layout is done with the circuit in tact, but omitting the original switching, LED and filtering is replaced by 470µ cap. Our "standard" polarity protection is in place and i've also added 1M resistor to prevent popping from the standard true bypass switching.. Tone 2 and Volume 3 connect together, there's a dummy connection for those on the board. Sounds nice now doesn't it? The pedal i mean..



60 comments:

  1. Replies
    1. Had to tweak it get them both in there :P
      +m

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    2. Haha... who said men never grow up!

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    3. Lol love the way it had to be the largest possible value resistor in there too, magnitude is everything right? Cant wait to build this, thanks for the layout, sounds like the 90's in a pedal.
      Thanks
      Dave

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    4. A big pink 'puff' with a circuit covered in schlongs? Hahaha, perfect. It sounds excellent by the way, definitely going to try this one out.

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  2. Is the 470uf cap absolutely necessary or could we omit filtering? also would a standard jrc4558 work, im assuming it will....
    Cheers
    Dave

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    1. We just tend to (usually) show the cap used in the original, but there is no reason why you have to go that high providing a smaller value is sufficient for you and your supply. At the end of the day if you aren't getting noise then you may not need anything at all, whereas some people may need a bigger value to do the trick. I don't think I've ever used a bigger cap than 220u and even that is probably overkill.

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  3. Cheers Mark, will probably give a 100uf cap a go then rather than wait for a 470.
    Cheers
    Dave

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  4. Nice! thank you guys for this layout!!

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  5. Hi guys, has anyone verified this one yet? I've just finished building it but I'm not getting anything out of it apart from a piercing osccilating whine when the volume knob is maxed. I'm pretty sure everything is correct.
    The only alteration I have made is to use a 100uf output cap.

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    1. You probably mean the filter cap..

      I'll double check the layout once i'm back home. Meanwhile you could measure voltages of the IC and probe where the signal dies.
      +m

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    2. Just checked it over and i'm confident about the layout. Feel free to compare this to Bajaman's schematic...
      +m

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  6. Hi Mirosol, I've got this working now (had a ground issue),and it sounds awesome. However the "Fluff" control does not seem to behave quite how it should. From max down to half way it seems to work as it does in the video demos, but as I turn counter clockwise it acts like a gate, finally cutting off the signal altogether just before minimum. Do you have any ideas what could be wrong?
    Even as it is the gating effect sounds great!

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  7. By the way you are right - I meant the filter cap.

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    1. So i figured :)

      There could be something wrong with the first gain stage (the left side of the opamp). Double check everything there - the fluff control acts sort of an volume control of how much signal is passed from first gain stage to the second.

      If you want to tweak it, you could up the 1K5 resistor coming from fluff lug 1. I would try something like 27K to 47K in its place.

      But. Seems like the layout works, so i'm tagging it. Thanks Beaker!
      +m

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    2. You could be right, the two LED's on the right of the board light up brightly enough to use them instead of a LED indicator, but the two on the left barely flicker (although that could be normal).
      I've probed everything and I'm getting good voltages from both sides of the IC.
      I'll check everything again, and try the resistor tweaks if I'm still getting problems. I'll let you know how I get on.
      Many thanks,
      Mark.

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  8. Ok Mirosol you can definitely tag this as verified.

    After triple checking the left hand side of the board and finding nothing wrong, I replaced the 1.5k resistor to "Fluff" 1.

    I had full sweep on the pot with a 15k and tried values up to 68K, before settling on 27k. This gives some angry spit and sputter on minimum, that disappears into creaminess by the time I turn up to 2.

    Maybe a trim-pot here might be a useful addition to allow people to tune the "fluff" to taste?

    By the way it can NAIL the guitar tones on "More Than A Feeling"!

    Thanks again, I really appreciate it.

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    Replies
    1. I built this today and have encountered the same behaviour, are we sure the original schematic was verified?
      Thanks
      Dave

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  9. I'm thinking the original schematic has a mis-print, i.e. the 1.5k should read 15k. I can't find the original schematic anywhere, so can't check it. If anyone has a link to it that would be helpful. However swapping the 1.5k for a 27k sorted things out, and I'm REALLY loving this pedal - so much so that I can't stop playing it long enough to get it boxed up yet!

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  10. Hmm I replaced the 1.5k with a couple of higher resistors and it doesnt seem to be making any real difference, I've gone as high as 68k and still the behaviour is the same.
    Thanks
    Dave

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    Replies
    1. Anyone any ideas? Had another fiddle with this circuit but I'm still not getting any signal below about 12 on the fluff knob.
      Thanks
      Dave

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  11. That is odd. Although I had the same issue, it was only the last fraction of a turn down to minimum (from half past seven down to seven o'clock)on the fluff knob. like I said,swapping the 1.5k resistor sorted things out.
    I hope you get yours sorted Dave. Hopefully someone will come up with an answer soon.

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  12. HI, I replaced the 1,5K with higher values. 1,5M works without the gating effect.

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    1. Interesting, I will investigate.... thank you for sharing your experience.
      Thanks
      Dave

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    2. Yes, thanks to Amo my cream puff is now creaming and puffing as it is supposed to, sounds fantastic.
      Thanks
      Dave

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  13. Good news guys, I will try some different, much bigger values and see how they affect the sound.

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    1. I'm pretty sure Amo is spot on with 1m5 being the stock value, upping this I think would just increase the amount of gain.
      Thanks
      Dave

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    2. Yes I know what you mean, but bear in mind that I got mine working with a 15k, and it currently has a 27k. I'm certainly going to try values up to 1.5 Meg - I'm really curious to see what it does to the sound.

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    3. Do you get the range of gain seen in the video demos? I mean 27k is vastly different from 1M5 so I wonder how our two circuits differ for yours to work with the 27k and mine not to.
      Thanks
      Dave

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    4. With the 27k I seem to get the same range of "gain" on the fluff knob, from about 9 o'clock up to max. Below that it starts to gate slightly giving some sputtering at minimum.
      As to why my build works with a far lower resistor value to yours and Amo's - I haven't the faintest idea!

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  14. Mine is working with lower values too, but with the gating effect below 12 o clock. The more I increase the value, the more the effect disappears.

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  15. Thanks for this layout - I've been hoping for this one! Looking at the schematic, the 10uf cap going to Fluff 2 is - negative to Fluff 2, and positive to the 2.2k resistor - also, the capacitor on IC pins 6 and 7 is shown as 390 pf. Is this correct?

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  16. I built this up as per your layout and encountered the same problems that others here have been reporting - so I made the changes described in my last post, (reversed the polarity on the cap between Fluff 2 and the 2.2k resistor - and changed the cap on IC pins 6 and 7 to 390pf) and the problem is now gone - and this is without changing the 1.5k resistor that others have replaced with higher values.

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    1. Thanks Frank, I've just finshed painting my enclosure for this, so I will try these changes before I drop it in and see how it goes.

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    2. This comment has been removed by the author.

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    3. If you're a member, you can view the schematic here -

      http://tinyurl.com/Baja-Pream-Cuff

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    4. Hmm, maybe I will put 1.5k back in and try this fix then, cheers for the heads up!
      Thanks
      Dave

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    5. This comment has been removed by the author.

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    6. Tone2/vol3 are connected to the board right next to a cut. So they're not connected to anything on the board. Should that cut be there? Or was that just meant to indicate that tone2 and vol3 are connected together?

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    7. That's something i tend to do. They just need to be connected together. I call that a "dummy connection" - and i do it because i personally hate daisy chaining pots. That makes my builds look sloppy - so i want to have all pot connections on board.

      I guess i'll need to add "there's a dummy connection on board" info to the images more often if one is present.
      +m

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    8. More like a "dummy" question from me. Just making sure before I threw it together. Thanks man. Enjoying the layouts you do here.

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  18. I have now got this boxed up. I have listened carefully to the video demos on my studio monitors and have decided that Miro's layout is correct, apart from the 1k5 resistor issue. Using a 1M resistor I can get this to sound almost exactly like the demos.

    However, the changes that Frank suggests sound different. It works, and works well but sounds smoother and bassier, but "duller". it's like putting a duvet over your amp.

    Miro's version definitely sounds better to my ears.

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  19. Hey Beaker, it's great to hear that you've been playing around with both ways. Have you had a look at the schematic posted at FSB? Mirosol said that we should compare this to Bajaman's schematic - and when I did, I noticed the two differences that I'd mentioned. There are even gut shots of a real Cream Puff posted, and you can see the component values and the 1.5k is there. I admit that I don't have enough understanding yet, about how changing components around affects the circuit - I'm a schematic "connect the dots" kind of guy! Maybe Mirosol can chime in and let us know how he came about with those two cap changes? Thanks!

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  20. Hi Mark and Miro
    I finally revisited this build today and used Franks corrections as he commented above. They work perfectly and I feel my build is now spot on to the original, just though you may want to correct the layout when you get a spare moment.
    This is one hell of a fucking pedal btw, just awesome.
    Thanks
    Dave

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    1. I'll be revising this soon(ish). The gutshots cover up the resistor from Fluff 1 with a label, but it is stated as 1K5 on those shots. Maybe i'll just swap the value vfor 1M5, as many of you report that it works like the demo with 1M5 instead of 1K5.

      The 100p is a copy/paste error, and the 10µ is in reverse. I'll fix those...
      +m

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    2. I think it sounds more like the demo with the 1k5 and the two changes Frank described but yes it did work and sound very similar with the 1m5 instead, strange.
      Thanks
      Dave

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    3. Strange is a good word. I don't think the vref voltage getting to Fluff cap is killing the cap that quickly. But if the cap orientation and value for the ceramic solves it.. That's how i'll update this.
      +m

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    4. Updated. Reversed the 10µ and swapped the 100p for 330p.
      +m

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    5. Yeah, looking at the gutshot pic, it's hard to view the color code on the 1K5 resistor as the last band is almost entirely covered up - I had to zoom in on that resistor to see the little bit of brown that is peeking out. So I feel confident that the value is Brown, Green, Red, Gold = 1K5. Thanks for the update!

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  21. I've just changed my pedal again to match this "new" layout. Sounds great - slightly different to the old one withe 1M5 resistor, but not as "wooly" as when I tried it last time.
    I'm now thinking I may have done something stupid like using a 330 nano cap instead of a 330 pico. Wouldn't have been the first time...

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    1. I'm still not done with this thing yet. I accept that the newly modified layout is correct - many thanks Miro, but somehow still preferred aspects of the tone I was getting out of this thing with the 1M5 resistor/ 100p/ and 10uF wrong way round, so I have been tinkering...
      That 330p cap shifts the frequency range of the tone control and to my ears at least, 220p gets the most pleasing sound out of this pedal, so guys, socket that one and tweak away!

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  22. it's a great sounding puff, how ever the output is too low on my build.
    the leds on the right side light up when i am playing, but not the ones on the left.
    are the ones on the left supposed to light up too?
    my voltages on the IC are (out of a 7,73v battery) :
    1: 2.59
    2: 3.75
    3: 3.70
    4: 0,00
    5: 7.51
    6: 2.60
    7: 3.79
    8: 3.64
    D3 light up when i was measuring some of the pins.
    is this an indicator of a grounding problem?

    regards,
    george

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    1. Left hand LED's do not light up, so that is normal.
      Mine has LOADS of output, so something is wrong somewhere.
      Stick with it - it's worth it!

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    2. Something very peculiar here, you have different voltages for pin 3 and 5 and yet they are connected directly via the two links under the IC. I think you're going to need to check placement of those links and/or the soldering

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  23. ah, thanks i'll check what's going on under those pins, later tonight.
    and yes, it's definately worth it, even at 20% of the estimated output i am amazed by the sound.
    regards,
    george

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  24. oops, i am terribly sorry yesterday i posted the last 4 pinouts in reverse. the correct voltages are:
    1: 3.59
    2: 3.75
    3: 3.70
    4: 0,00
    5: 3.70
    6: 3.77
    7: 3.60
    8: 7.54

    i will reflow them anyway and see what happens.

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    Replies
    1. there is something weird going on with my build. i can measure 4.01V from output (volume lug 2). i am not a genius in electronics, i think that outout is about audio signal only, no DC current passing by, right?

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  25. finally i got it working!
    the 1uf Cap above the 8pin of the IC was off. it was acting like a jumper cutting out most the output. probing with an axial cap from the +side of the cap or from the upper sides of D3 or D4 to the 20k resistor i can get a hugh output.
    the only thing i need to look out is an oscillating sound when fluff is at max. setting, but since i am on the creamy side of the puff, i don't mind that much.

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