Friday, 15 August 2014

Walrus Audio Mayflower

Thanks to Matt for his schematic for this buffered Timmy.  Info about the original:

The Mayflower is a true bypass, midrange overdrive pedal that falls in-between the Voyager’s low gain preamp settings and the Iron Horse’s full and harmonically rich distortion. The Mayflower boasts a transparent, midrange signal that is great for cutting through or adding to the rhythm. It includes Level, Drive, Bass and Treble controls for a large range of tonal versatility. The Mayflower provides a transparent and organic sounding breakup that allows tweaking and shaping to boost your original tone.








Only one channel of the second IC is being used, and that is only being used to buffer the reference voltage.  There are a lot of pedals that work perfectly well without doing this, not least of which the pedal it's based on, and so as this is a low-ish gain Timmy with buffers I'm not too worried about excess noise.  So to save space this layout removes the second IC completely and just uses a normal unbuffered voltage divider for vref.  I don't expect any significant audible differences between the two so I think this is the one I'd build.



55 comments:

  1. This looks interesting - thanks for posting this IvIark. I am assuming that since the transistors here are just part of the input/output buffers, we can replace the MPSA18s with other choices (e.g. 2N5088 - making sure the pin outs match)?

    ReplyDelete
    Replies
    1. Yes no problem, 2N5088s would have the same orientation

      Delete
  2. Nice, definitely going on the todo list...

    So the mayflower is a timmy, the voyager is a klon. I wonder where they got their inspiration for the iron horse ...

    ReplyDelete
  3. Nice sounding pedal in the demo... Good enhancement for that Tele / Princeton Reverb amp and a great addition to the overdrive family... good stuff!

    ReplyDelete
  4. So why not build a Timmy then?

    No sarcasm intended.

    ReplyDelete
  5. wow, yeah i dont know. comparing the schematics, the only differences i see are the voltage supple, in/out buffers, # of diodes in the gain stage (and clipping obviously), and a couple of part value changes. but that's it. not much. curious to know how much those changes affect the sound

    ReplyDelete
    Replies
    1. Though I'm not Mark, I think it is different enough to give it a try. A bit more lows due to the larger input caps, lower gain and less "agressive" clipping - in a nutshell I'd expect this.

      Delete
    2. If I were to build this, I would try a larger gain pot for more drive (A1M versus A500K), and perhaps play around with the treble and bass filter caps. Also note that if the LED is part of your boxing process, you don't need the LED resistor or output wire. The great thing about DIY building is that you can mod these designs to make an effect truly customized to your own tastes.

      Delete
  6. I could be wrong here... but the 3k3 resister going to the bass control... doesn't that come out of gain 1? ... On the board, it's coming from gain 3. maybe i'm misunderstood though (looking from the schematic posted of course)

    ReplyDelete
    Replies
    1. yeah, i think on the board, just gain 1 & 3 are reversed

      Delete
    2. I did the layout based on Matt's original schematic and it looks like the lug numbering was swapped, and thinking about it the second one is correct so I'll need to swap it in the layout.

      In terms of differences to the Timmy. Well not a lot really although the buffers should allow it to play better with a wider range of other pedals. Apart from that there isn't too much difference. Less clipping options of course, and the 5K1 instead of 3K3 in the final stage means it only has 1.65x gain in the final stage instead of 2x.

      At the end of the day it may be something worth building just to see how those changes affect the results compared to the Timmy. I certainly wouldn't buy one though.

      Delete
    3. cool. i'll give that layout i sent you a shot. any clipping options we can use for this as well?

      Delete
    4. Well you could add another two diode to a switch to give you the more and less compressed modes. Check out the latest Jan Ray layout to see how to connect it up

      Delete
    5. So is the Timmy kind of mid-rangy as well for an overdrive pedal? I have never really tried one of those before and how does it compare to say a klon or tubescreamer???
      Kind of hard to tell with demos on youtube

      Delete
    6. cool. i'll do that for some more variety. thanks :)

      Delete
    7. No the Timmy is very flat in the mids although you can of course give yourself a bit of a boost by lowering the treble and bass settings. It's not my favourite overdrive, I don't think the drive on its own is much better than a lot of other pedals out there, but it's the best stacking overdrive for me bar none and a lot of that is down to the EQ. Zendrive > Timmy is musical ambrosia to me. I love the Zendrive which is one of my favourites, but with the Timmy as an EQ and added gain stage following it it allows you to take it up a notch and you can get some really high gain sustaining distortion from it.

      Delete
    8. I made a sweet pedal template for a 1590BB enclosure that is a Timmy/Zen
      I am going to make a combo with order switching option. Very exited about this build and will keep you posted... when it is done I will post pic links over to the hmmm... Zen thread LOL thanks again! (if anyone wants the template for the graphics... let me know.. in photoshop

      Delete
  7. Replies
    1. Excellent thanks Will. What do you think of it?

      Delete
  8. I love it! Using 5088 until I get some mpsa18. I think the zendrive will be next.

    ReplyDelete
  9. Did you build the version with or without the vref buffer? I'm curious about the noise levels this puts out. I'd mostly build this for "stacking" so I'm hoping it's low/no added noise

    ReplyDelete
    Replies
    1. You never know, but I'd be extremely surprised if there was any significant noise difference between the two layouts. To me buffering the reference is a worthwhile thing to do with an unused channel which is the only time I can recollect ever seeing it used in any of the past layout circuits (except maybe a couple of the bigger, higher gain, and/or more elaborate or expensive effects which included every bell and whistle). But to include an extra IC specifically for it, particularly with a lowish gain overdrive which didn't have one in the original it was copied from, makes me suspect that it's filling out the PCB, making it a visually more complex looking two IC effect, and trying to distance itself further from the Timmy.

      But after a few years of seeing many hundreds of obvious clones, I may have turned into a complete cynic who is hyper critical in the way I see things :o)

      Delete
    2. you think input and output buffers make a difference, sound wise?

      Delete
  10. I hadn't thought of it that way but it's probably true. Walrus Audio seems pretty full of shit but maybe it's just me

    I have all the parts for this and a spare 125b drilled for four knobs. If I get a chance this weekend I'll probably build this.

    ReplyDelete
  11. I built this one tonight, and after two solder bridges and one cold solder joint (grrrr...) it works! Sounds great and all controls function as they should. I'm using a C50K pot for the treble control, but that's not essential. There's enough gain using the 500K gain pot, but if you wanted more you could try reducing the 5.1K resistor to 1K (or even make a switchable boost). I'm going to play around with the circuit for a few days, and then eventually box it. I also want to try this in front of my Zen drive clone to see how it stacks. Thanks again IvIark!

    ReplyDelete
  12. Newbie question here: so does the Gain 3 on the board go out to the Gain pot, lug 3, and then a connection from the pot to Treble 1 & 2 lugs? Can it be one connection that goes out and connects to the Treble lugs by bridging 1 & 2, or should it be separate connections to each lug?

    ReplyDelete
    Replies
    1. yes. bridging1&2 is the best way.you can also take a wire from the hole between gain1 and gain3 and solder that wire to treble1&2 cause as you can see in the layout this raw is connected to gain3 via a small link between 1u and 100pf, so you'll be ok with that too.
      generally you can go anyway you want, as long as the electricity passes wherever it should pass.
      hope i helped

      Delete
    2. Awesome, thank you for your help! I figured bridging would be the easiest but just wanted to double check. Thanks!

      Delete
    3. This comment has been removed by the author.

      Delete
    4. I finished this one up tonight (using the first layout with 2 IC) but don't get any audio when the switch is engaged. I've checked for solder bridges and everything looks clean, double checked the layout/links/cuts, and I've also tried swapping out each IC. I'm getting 8.3V testing at the board's 9V in and ground and I'm getting the LED when engaging the pedal, are there other places I could test readings to see what's passing through/going on?

      Delete
    5. Chad - post the voltages you get at the pins of the transistors and the ICs - that should give a better idea. Also, I am assuming you have read through the troubleshooting guide (link button "faults" at the top of the page)

      Delete
  13. I've gone through the fault guide and the only thing I'm not sure of how to do/where to test on this one is for continuity. Solder joints all appear to be good as well, but it wouldn't hurt to reflow them as well.

    Here are the readings I'm getting:

    TOP/CENTER IC:
    1 - 8.08
    2 - 8.06
    3 - 8.21
    4 - 0.1
    5 - 8.05
    6 - 8.61
    7 - 8.61
    8 - 8.65


    BOTTOM/RIGHT IC:
    1 - 8.62
    2 - 8.62
    3 - 21.1
    4 - 0.1
    5 - 21.0
    6 - 8.06
    7 - 8.06
    8 - 8.65


    Q1:
    C - 8.64
    B - 7.73
    E - 7.48


    Q2:
    C - 8.64
    B - 8.61
    E - 7.99

    ReplyDelete
    Replies
    1. hi chad.
      there is a problem almost everywhere...
      especialy with that 21v!!!there is not a place that you could start to solve this...you could upload pictures of your board (both sides.)
      you should get round 8,5 volts,only at pins8..and your grounds should be clear 0.not even 0.1...all the other pins should be around 4,2v-4,5volts.

      Delete
  14. Hey, so is the first lug on the bass pot not being used? Or am I just overlooking it?

    ReplyDelete
  15. Hello, can I switch the 1uF disk caps to 1 uF electrolytic caps? And in that case which direction should the be facing?

    Thanks in advance

    André

    ReplyDelete
  16. Just built this and it sounds great. it does have some hiss and a bit of pop when turning on/off. not sure if its the pedal or what. I looked everything over and it looks legit. Anyway it does sound great! I just might build the version with the two IC and compare the two.

    ReplyDelete
    Replies
    1. I ended up building two of these and they both have a pop when engaging, and both are using different switches. Sounds pretty good otherwise, but I do prefer the Timmy build a bit more.

      Delete
    2. were both of yours the 1 IC or the 2?

      Delete
  17. This comment has been removed by the author.

    ReplyDelete
  18. Hi guys.
    Can you tell me what kind of resistors can I use instead of 510K and 5K1?
    Thanks!

    ReplyDelete
  19. Mine also pops like crazy, tried a pulldown resistor at the output, bigger pulldown on the input, and no dice. Any advice on this?

    ReplyDelete
  20. Mine also pops when engaged but sounds good otherwise. Does anyone have a solution for this pop?

    ReplyDelete
  21. this is bullshit, tried everything, removing the led, pulldown resistors, even making this buffered bypass, and no dice. The fix is: built yourself a Timmy

    ReplyDelete
  22. Have you looked at that 10uf output cap? We've had switch pop issues caused by a faulty electro output cap

    ReplyDelete
  23. Travis, I even changed it to a 1uF metal film capacitor. I think there's a mistake in the schematic posted at FSB, messing with the impedance or something like that

    ReplyDelete
  24. Jeez. Well I'm pretty much out of ideas for a solution then. Sorry. The original Timmy seems more interesting to me anyway

    ReplyDelete
  25. Yep! I gave up on this one (unless I put my hands on the original and find the mistake in the schematics and report it here). I just modified the values on a Timmy board to match this, and sounds almost spot on

    ReplyDelete
  26. hey, mine also pops, have you find something about the schematic/layout? I built it for my friend, tried several in-out caps but still pops like #&@&|. I will try that Timmy-thing. Cheers

    ReplyDelete
    Replies
    1. Okay, when I almost cut the vero for it with added TS buffers I noticed that there is a 10K shunt resistor on the schematic of the Tube Screamer output buffer which is missing from the layout. Added that and bang! no pop at all(at least in my test box).

      Delete
    2. whoa, that's nice! I'll give it a shot

      Delete