Friday, 24 February 2012

Mad Professor Sweet Honey Overdrive

Mad Professor's "Honey Bee"-esque offering.  Manufacturer's info:

Mad Professor Sweet Honey Overdrive (SHOD) is a super touch sensitive medium gain overdrive pedal.  This pedals is now offered as lower priced pcb-model or hand wired pedal. Both share the same specs and tone.  It is designed to overdrive distorted amplifiers and give dynamically controlled light overdrive on clean sounds.  Distortion level can be controlled by pick attack and pickup strenght. Harder picking for overdrive and softer for cleaner tone.

With the unique Focus control you can adjust the feel and dynamics of the pedal as well as overal EQ.  Turning Focus CCW you need to play harder to get distortion and the tone is softer, great for jazz and blue.  Focus turned CW gives a slight treble boost and earlier distortion.

This type of overdrive has previously only been found in the BJF Honey Bee but is now presented in Mad Professor version. The Mad Professor SHOD has a tighter sound and is more versatile as it was designed to work with all kinds of guitars and amplifiers.

This versatile pedals stacks well with all kind of other pedals and suits for huge variety of different music styles.

Controls:

VOLUME: sets the output volume
DRIVE: controls the amount of overdrive.
FOCUS: Controls how easily the circuit distorts as well as adjusting overall EQ. Turning CCW gives less distortion and a mellow effect, turning CW gives a slight treble boost and earlier distortion. Good starting point is 11 o’clock.



Oops, I think the LEDs should be red which should give more distortion and compression.  Try this one, and consider socketing the LEDs so you can experiment to see what you like best:



BUY A KIT

139 comments:

  1. Thanks for this one! Are there any IC alternatives ?

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    1. Hi. You can use any dual opamp with the same pinouts such as the JRC4558, NE5532, LM1458, TL072 etc. I believe the OPA2134 is a good alternative but they also tend to be quite expensive.

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    2. I was working on this project, but its layout is cleaner. I think you can use the NE5532, LM833 or TL0xx.

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  2. Trying to figure out both of the grounds here. I've connected both and it grounds out the entire signal. Just wondering where these should go?

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    1. The ground wires from the board need to be connected to all the external grounds, like the DC adpter, input and output sleeves and switch.

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  3. pretty impressive what you've got going on here mark! i think i started following just before the 100th verified layout, and that seems like it was only yesterday! anyways, i finally got around to finishing this one up, so it is verified. this is the second " honey " that i've built. the first being the bearfoot honey bee. i built this one with red LED's and the OP275 chip. sounds great! this one definitely has more drive and grit than the bearfoot. sounds dirty without being over the top. i was playing them back and forth trying to decide which i like better, and i found out that playing the sweet honey into the bearfoot honey bee at low settings sounded awesome! i'll have to play around a bit more i guess. as always, thanks again mark, and keep them coming!

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    1. Brilliant, thanks for verifying mate. Don't worry about which is better, just build them all and have an immense collection for any occasion! :o)

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  4. OK I may be acting juvenile, but everytime I look at D2, the 3K resistor and D3, I snigger ....

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    1. Haha, class! ... Well if that juvenile then I have issues as I still enjoy drawing cartoon willies on my mates work notes....

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  5. http://mirosol.kapsi.fi/varasto/boxes/ShOD.JPG

    Better than i expected. Soft/fat overdrive and not a distortion. Used AD712 and subbed a few resistors to be closer to more standard values :)
    +m

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    1. Surely, one of my next builds. For what I see, drive pot gets lug 3 unconnected, is it right?

      One curiosity, as i've never used before leds as clipping diodes. Will the leds light up when the unit is powered?

      BR!

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    2. Right. Drive 3 is not connected.

      Those LEDs light up brighter the harder you hit the strings.
      On my crunchbox v2, i too them outside:
      http://mirosol.kapsi.fi/varasto/boxes/cruncher.jpg
      +m

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    3. Finally, could not resist the tempation and built it yesterday late evening.

      Sounds ok, but I only get one led lighting up when I play, the one at the right of the 3k resistor. Both the two remaing never light up, nor the left resistor's nor the one at the side of the 5.6k resistor at the right of the vero.

      Can you confirm that your 3 leds light up? If so I have to assume i've burnt 2 leds in a row.... first time it happens to me... will have to check it this afternoon.

      BR

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    4. Well, checking now: Both "Juvenile" ones work fine a,d light up as you play, the loder, the brigher, but the one at le right (following the 5.6k resistor) does not...

      Let's see next time i plugg it :P

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    5. I was just about to write that i have the pair blinking and and third one not.. So that's the behaviour we want :)
      +m

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    6. Thank you very much once again Miro!

      So correctly build :) I will box this one. Third Bjorn pedal I build, thir that gets boxed. This guy is becoming my idol!

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    7. I promised that woud not build another pedal in a month.... but temptation, Miro buildin it and telling it's great, and having all the needed components at home.... had no chance but building it :P

      The pic for your collection, Mark:

      http://img593.imageshack.us/img593/419/sweethoney.jpg

      Really sounds fine, sweet low - medium overdrive that (great!!!!!) does not remind me of a TS!!!!!!

      BR

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    8. By the way, the third led (the only no juvenile :P), lights for tenths from time to time when moving the different pots.

      I still don't understand the function of this led, can't imagine why is used/ placed there .

      On the other hand, is really funny to see the other leds blinkin' as you play, my box was drilled previously, but on next pedal using leds for clipping, I'll take them outside!

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  6. Hello folks!

    I was just wondering about those 1u caps... I have some poly film box caps that I could use yet the ones on the board seem to be polarized? Should I use electrolytes instead?

    And also, a general question... I have plenty of box caps yet very few ceramic discs. These are 5mm raster and oftentimes they don't fit the vero. Should I solder some pin extensions on my box caps and make them fit or should I go fetch some ceramic discs that have bendable leads?

    Thanks!

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  7. Oh yeah, and one more thing. Seeing that there are a few funky resistor values that I can't source right now (13k7, 2k61), just how crucial are these (and if they aren't, what substitute values would you recommend)?

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    1. Hi Goran - don't know if it's any help but I just bought the kit from www.bitsbox.co.uk - using the link above, he has the obscure resistors in stock, as part of the kit. I've ordered things from him before and he's always fast at shipping.

      If you're unable to order from him, I would imagine that subbing the resistors for the nearest available values (maybe 13k and 2k7) won't make too much of a difference - unless someone on here knows otherwise?

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    2. Thanks for that info, Dan! I'll check out the bitbox site.

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  8. Hi Mark,
    First, thanks for all the great help and the amazing and easy to follow layouts.
    Last week I finished the first from three of your kits (Klon Centaur) and it definitely is far above my expectations. Thumbs up!
    Today I completed the "Honey"... works great so far, with one exception - the couple of LED's are not blinking. I do not care to much on the "fashion" side, but might this indicate some fault in my build. Sound wise, the kit is working OK.
    I would appreciate any advice... some values I should measure and compare with a "blinking" one ?
    I consider myself a newbie in electronics, so do forgive me if I ask any stupid question :)
    Cheers and thanks a lot!

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    1. The LEDs are used as clipping diodes, not for indication and so the signal isn't necessarily strong enough to illuminate them. Maybe someone else who has built this could say whether their LEDs illuminate or not, but it really isn't important whether they do or not for their intended function within the effect.

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    2. HI,

      D2 and D3 should blink, the harder you play, the brighter they'll light up, I thought about placing thme outside to see the effect as i find it amusing.

      D6 lits sometimes, very rarely, when adjusting pots, but it usually stays dimmed.

      BR

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    3. By the way, I used 3mm red difused leds. I tried too green super brights,and the blnking effect was not so visible.

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  9. I really do not care if they blink or not. All I care about is if they do not blink, does this necessarily mean there is a fault in my layout? Thx guys!

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  10. If you socketed, (and you should always when it comes to clipping), put a pair of 1N914's or other diode in place of the LED's. If the volume drops considerably, the circuit is working, just a different level of clipping. As stated above, aggressive picking will usually result in some level of illumination but not always, depends on volume level (pedal and PU type. I find that my Humbucker nearly always generates some level of glow, but the single coil(s) will not. Volume needs to be 10 on the PU and up some on the pedal as well. Not an expert, just my experience.

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  11. Thanks Pete !
    That was what I needed ! Much obliged !
    The drive is very sweet and I assumed I build it in a correct way, however, I wanted to check second opinion. Thanks again !

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  12. Hi,
    Does the the LED+ on the board mean that i can connect the positive led leg direct to the board instead of the dc jack?

    Thanks, Ben,

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  13. A question about the bitsbox kit: One of the 1uF caps is a classic box-type, and the other is a multilayer ceramic cap. Which is which?

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    Replies
    1. Bitsbox supply box caps for 3 row spans so it is correct for the 5mmpitch, and multilayer ceramics for spans greater than 3 rows.

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    2. Don't I feel silly now.. :) Thanks!

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  14. Do they have to be 3mm red leds or can I use 5mm? Will there be any difference?

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    1. 5mm is fine, no difference except they take up more room on the board

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  15. quick question about this diagram (and i guess all the diagrams on here) for the ic which one is pin 1? i always seem to put them in backward

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    1. http://www.analog.com/static/imported-files/data_sheets/OP275.pdf

      Notch/dimple on top on all layouts. Left side from top 1-2-3-4, right side from the bottom 5-6-7-8.
      +m

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  16. So close on this one... just have to find the trouble with my gain pot not working. It sounds pretty crunchy and nice now though.

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    1. After looking over every component and reflowing all the solder points and checking for bridges I decided to give it a day to sit. I came back and found the problem within 5 minutes. Never underestimate the power of doing nothing... take a break and it may become blatantly obvious. Another great layout! Thanks Mark!

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    2. Someone slipped into my house in the middle of the night and wired the pot with the right spacing, but to the wrong row on the board. One of those, "wow that's the first thing to check" moments. Probably won't get put on my gig board, but it sounds nice and dynamic.

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  17. alright I'm about to pull out my hair over this, i got it all together but when i turn it on nothing, ive checked all the basic stuff, (cold solder joints, unwanted bridges, made sure everything was in the proper place) when i turn it on all the pots work (they change the sound of the hum of my amp) and when i touch anywhere on the board it pops so everything is connected. none of the onboard led's are lighting up and i tried changing the ic, anyone have any ideas? im really hoping that one of my components isn't bad but i can't think of anything else

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    1. I've built the SHOD very recently, it's actually sitting right here on my desk waiting to be boxed. :)

      I don't recall having any issues with it, it fired right up. My wild guess about your problem is that you probably have a grounding issue. If everything seems to be where it should be, you've taken the scalpel to all the track spacings (bridges can be very hard to spot) and you still get no sound, I must recommend using an audio probe and tracing the signal path. It's an invaluable tool and all you need is a 100nF cap and a couple of alligator clips. There's plenty of info on the interwebz on this but I can walk you through it if you need me to. If you need IC voltage readings from a working circuit, I can do that as well because like I said, it's not boxed up yet and more importantly, I know exactly where it is. :)

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    2. im pretty new to this, i probably can just look up how to use the audio probe but the ic voltages would help, thanks a lot

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    3. I'll write them out tonight when I get home from work.

      Do fabricate an audioprobe, it really is very useful and costs almost nothing. It makes it easier to narrow down the circuit problem areas for people to help you out with.

      I don't even have one dedicated audioprobe, I just use two wires with alligator clips and probe with one of the cap leads. :)

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    4. haha nice, i just found a vid on youtube teaching me how to do it, what kind of capacitor should i use? in the vid i think he used a .01uf. does it really matter?

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    5. I don't think it does, I've seen people use all sorts of things. You aren't shaping your tone, you are searching for absence of signal so which frequency band gets through your cap is really of little importance in this case. :)

      I'd just make sure that the voltage rating is higher than what you are probing but other than that, it's fair game (I'd just skip on the electrolytics, all too easy to get the polarity wrong in the wee hours of the morning when I usually tinker with pedals :) ). Usually I just use one of these, Tayda's 100n come with long leads which comes in handy
      http://i.ebayimg.com/t/POLYBOX-CAP-0-015UF-63v-5mil-Pitch-x5-/07/!BUCeUIw!mk~$(KGrHgoH-DgEjlLl0b,6BKLh5!S3Jw~~_12.JPG

      If you are looking to box it inside a dedicated cable, go for any ceramic/film you can find. 100nF is a common value.



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    6. alright i think i found the problem (hopefully). it turns out that i used .47n caps instead of the 4n7 ones. ill have to try and get ahold of some with the right values to find out, fingers crossed.

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    7. I'm just fishing here because it's been decades since I learned (and forgotten :) ) about these things, but 4n7 caps value change shouldn't affect your circuit the way you describe. I'm talking about C1 and C3 on this schematic:

      http://3.bp.blogspot.com/-eWf8bulApFQ/TxAQlYh4VQI/AAAAAAAAAc4/nawMm2aJJ6Q/s1600/SweetHoney_schematic.png


      IIRC, the input cap along with the resistor forms a high pass filter that stabilizes the rest of the circuit from whatever it is that you plugged SHOD into. Read up on high pass filters and see how it affects the frequency spectrum of the signal entering your SHOD.
      Output cap also forms a high pass filter that can pass or block certain frequencies as required and it also blocks any dc signal that you might have left.
      Again, I'm really fuzzy on the details after all this time, but it shouldn't completely shut down your circuit if your values are smaller.

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    8. Alright, here are the IC values:

      1 4.30
      2 4.27
      3 4.11
      4 0
      5 3.87
      6 4.27
      7 4.32
      8 8.46

      I measured it with all pots fully maxed out, guitar plugged in but not played. Also note that I used OPA2134PA as suggested in the comments but it shouldn't make much of a difference.

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    9. i checked the voltages and they are all pretty close, i also changed out those caps but still nothing. i used the audio probe and most of the signal is being lost in the input cap and by the time it gets to ic 1 its completely gone

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    10. Referring to Mark's layout and the schematic I posted above, you're saying that you have virtually no signal on both ends of 6k8?

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    11. there's less than half the original signal at the bottom and none on the ic side

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    12. I'll check my board in couple of hours when I get home.
      Luckily I still haven't boxed it and given it away as promised. :)

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    13. This comment has been removed by the author.

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    14. There's definitely something wrong with your board (duh! :) ), something is pulling your signal to ground.

      I just audioprobed my circuit, there's no discernible volume loss at either end of the 6k8. What I hear at input point is what I hear at IC pin3. Amplified signal comes out of pin1.

      Now, there are not many components between pin3 and input and if you say that you exchanged them and the new ones are functional, there's no other explanation other than a solder bridge or a cold solder joint somewhere. You shouldn't lose any signal on 4n7 or 6k8. Something is interfering with your signal path. First try reflowing and then take a sharp utility knife / scalpel and score between the strips containing these two parts (you may as well score the entire board while you're at it :) ).
      If you have a magnifying glass, use that to make sure there are no solder bridges. You wouldn't believe how tiny they can be...

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    15. if you still have it can you measure the voltage at vb and vr on the schematic, ive gone over it four or five times looking for solder bridges and nothing... i'm getting around 4.5 volts at vb

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  18. Mark, what if I used yellow leds? How would that compare to red/green?

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    1. They have a higher forward voltage and so will clip and compress less. Always worth socketing and experimenting with the diode/LED clipping points.

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    2. Thanks!

      I didn't socket because I fully intended to have the leds inside the box but now that I'm boxing it up together with a RC Booster, leds light up more so I thought why not have them on the outside. With it being a honey themed thing, yellow can't be avoided, now can it? :)

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  19. Hello Everybody!

    I have a problem with my sweet honey!!
    I have only the volume knob working!!
    has anybody still had this problem?

    Many thanks, it's my first pedal!

    ReplyDelete
    Replies
    1. It could be anything, one component in the wrong place could stop things working as they should so we need a bit more info to have a hope of helping you. What voltages are you getting at all the IC pins?

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  20. Thank you for the answer...
    I have almost the same voltages on the IC pins than the values we can see above in the post!
    i m not very sure in the wiring of the pots and the 3pdt switch... i've seen on the web a lot of schematics and i'm a little confused...My LED lights on/off, the volume knob work, and when the footswitch is engagers, there is no drive, and it's almost like if my pedal was bypassed...except the volume....
    I will unsolder the pots, check the board (if i have no bridge) and pray!!

    Thanks for your help!!

    I have builded some Preamps Kits (Neve and Api Clones) but i find it's a little bit harder to find all infos(the good ones!!)

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  21. swwet honey in front of the stone grey distortion.
    went on with NE5532 for this one.
    http://www.youtube.com/watch?v=YZqQLVe8gsQ
    http://instagram.com/p/Xns2-AxWIy/

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  22. Hi Mark
    Many thanks on a wonderful resource you have provided here.
    A total idiot question: how does the indicator LED wire up? LED+ from board to the LED, ok, but then? LED to switch or input?
    Thanks for any advise, medical or otherwise, you can give me.
    h

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    1. LED+ from board > LED anode
      LED cathode > switch > ground

      The diagram here gives a good visual guide as to how the LED connects:

      http://tagboardeffects.blogspot.co.uk/2012/02/offboard-wiring.html

      Except in this case the resistor is included on the board so you just have to take a wire to the LED anode

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    2. Thank you so much. The above diagram threw me a little, and my stupidity did the rest.

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    3. Hi again - all wired up and checked, pots all respond, but I am getting a very tinny sound. Have I made some obvious mistake on the board and used the wrong cap on the focus circuit somewhere? If there's an easy reply, thanks, otherwise I'll muddle through, I wasted enough of your time already.

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    4. No time wasted, don't worry. :)

      Don't know really how to help you, this is a great sounding overdrive and probably the best one I ever made. I'm not really on board with all the pedal lingo yet and can't really say what do you mean by tinny but it doesn't sound right for this pedal.
      Maybe you can try a different opamp in there? I'm just guessing, check the pinouts before you go sticking a different ic in there. :)
      I'm not sure if it has anything to do with the tonestack or is being "tinny" only a function of gain so I'll let others take over from here. :)

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    5. Hi Goran, thanks for your input. "Tinny" means no bass, too much treble, an unnaturally bright sound, that's why I thought I might have messed up the tone circuit. I will check the pins again, good idea.

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  23. I have everything wired up and bypass at least works, but nothing else. Soo...2 newbie questions:
    - It says Volume 2 goes to ground. Can I take that to the bottom ground strip to just link off the board?
    - That bottom ground, can I then take that to the top ground strip and then just solder the ground from the DC jack to that strip?

    Any help would be much appreciated.

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    1. Volume 1 to ground in the first question...sorry...

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    2. All the ground points including offboard need connecting so yes the bottom ground strip on the vero could be used for that.

      You really want to test the circuits before wiring up the switch or you're introducing another potential point of failure that needs to be checked.

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    3. How can I test the circuits? I've checked out the Faults page, but it doesn't seem to say how I can test a circuit standalone. I have a multimeter, so I should have what I need. Thoughts? Thanks for the help.

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    4. Just a small terminal block to attach the socket wires up to the effect input and output, like this:

      http://i76.photobucket.com/albums/j6/IvIark_2006/DIY/Mark%20Builds/1012110003_2.jpg

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  24. This one sounds really great. I went with green LEDs as I didn't really want more distortion and compression from reds. Haven't built the Honey Bee yet to compare the two, but I might have to before boxing one or the other up.

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  25. I just built and tested this SHOD layout (w/red 3mm LEDS) and it sounds great. thanks for posting it Mark!

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  26. got mine completed. YAY!

    pics:

    http://johnkvintageguitars.homestead.com/Effects/Fuzz-ODs/BJFE/SHOD-01.jpg

    http://johnkvintageguitars.homestead.com/Effects/Fuzz-ODs/BJFE/SHOD-02.jpg

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    1. Very nice! I wish mine came out that neat...

      Where do you get that green vero?

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  27. thank you for the layout mark, your site is keeping me very busy, i am going to have to take a break and actually play some guitar! im loosing my chops
    cheers!

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  28. This comment has been removed by the author.

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  29. Hi. Actually, shoulda done more testing before posting. So, just finished building this, and it works; sorta. The gain pot works, I can hear the focus knob changing the tone, and the volume knob works. But even maxed out, the output of the pedal is about half of what the output is when the guitar is plugged straight in, and there is a lot of noise going on - but with a weird twist. When I back off the volume knob a smidgen, the noise goes away, although it's still very low output. (I actually removed the volume pot to see if it was the pot). My first thought was ground, but seems OK. I checked everything else, bridges, etc, couldn't find an issue. IC voltages correspond, except on pin 5; only getting 2.2 volts there. Was wondering if this is one of those "oh, you clearly XXXX" problems? ...
    Thanks

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  30. you must have a misplaced component, a solder bridge, or a bad cut somewhere since the circuit works perfectly if built exactly like the vero.

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    1. ah. Thanks, figured it out. As expected, I made a dumned mistake. Turns out my 100u cap was not 100v like I thought it was (maybe wishful thinking, was the one lying around), but 10v. Dang zeros. hah. Replaced it with proper voltage cap, works great. Hopefully this will help someone in the future if they make the same mistake. Thanks, great forum here.

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    2. I "finished" this build today and get problematic sound. Seems that there is a threshold above which the signal is propagated.
      After checking the layout, parts, possible bridges and finding nothing wrong on that part, I came here and read this commment on Cap voltage. Is it critical? I have a 16V 100uF capacitor. Could that be the issue? How would a too low voltage spec on the capacitor manifest itself?
      Thanks, Haaf

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    3. There's no problem at all using 16V caps unless you're supplying it with 18V. I use 16V 100u caps in virtually everything and as long as the rating is higher than the supply voltage it's never a problem.

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    4. Thanks for the quick reply. On with the search then. I guess I better build a audio probe.

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    5. First thing to do is measure all the IC pin voltages, that will give the best clue

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    6. Will do that as soon as i have time again. Will work on it later this week.

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    7. Finally got some time: this is what I got:
      1: 4.2V / 2: 4.2V / 3: 3.0V / 4: 0V / 5: 0.8V / 6: 7.7V / 7: 7.7V / 8: 8.3V.

      Most of this looks normal to me: V+ and V- are ok. The output and minus-input of both opamps are equal. The fifth pin is were I seem to get different numbers from reported in other comments. I interpret the 0.8V as the forward voltage of d4 and d5. SO it seems teh voltage of teh voltage divered (the 2 47k resistors) is not coming through. Defect D1? But that cannot be teh case since teh voltage on pin8 is 8.5V... Any ideas?

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    8. Still not there...
      I build a audioprobe and follwowed the signal. Sure enaough teh signal is fine on teh input of teh secodn op-amp (pin5). At the output the opamp (pin 7) the signal is really bad ("broken up"). That probably has to do with the 0.8V voltage i get on pin5.

      I checked the voltage between the two 47k voltage divider resistors: it is 4.07V.

      Since the only route to ground of that voltage is through PIN 5, and impendance there should be huge I expect there is a leak to ground elsewhere. Any ideas?

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    9. check al connections, cuts, bridges, componenet values. I'm out of dieas and close to just starting all over. :-(

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    10. Been thinking about this one a bit more, and I'm confused about the 1M resistor that is linking the 4volt offset from the voltage divider to the input on pin5. (I understand that thisis to get teh DC level well within teh workig range of teh opamp)

      This is what I wonder about: If a small leak current exists, the voltage drop becomes high due to the high 1M resistance. Woudln't 100K be a better choice? What consiration would require a 1M resistor?
      Sorry if these things are stupid and don't make sense to those that have a better electronics uinderstanding than me.

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    11. I don't know whether a different value would be better, but the 1M was used in the original and it has been built by a lot of people so I don't think that thinking about how it works will solve your problem. The voltage is too low on pin 5 as you say and so the IC is either damaged or something is pulling it down. Are you sure the cut between pins 4 and 5 is ok? A micro bridge or a copper burr left in the cut could answer why you're losing signal.

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    12. Thanks, I'll check again. And I'll put in another opamp as well.

      ps I'm just trying to figure out how this thing is supposed to work; hoping it helps in identifying what DC signal to measure where,

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    13. TL072 did slightly better (I think it works slightly better at teh low voltage). But voltage remains low at pin5.
      4558 did worsse soundwise, and similar bad for teh pin5 voltage.

      SO it's not tHe.

      I'll sleep a night on it.

      Thanks for your help. I appreciate it a lot.

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  31. Done, w red LEDs, socketed might try the greens if i feel its too distorted. thnx guys

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    1. Sounds AMAZINGGGGGGG (red LEDs, not gonna change em, sounds like how it does on prymaxe and PGS), thnx Miro and Mark for your hard work, made it w the kit from Bitsbox (since it was my first time) - truly and amazing pedal.

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  32. Finished boxing this up tonight and I LOVE it. Thanks to all of you for your help.

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  33. Getting oscillation on full drive with AD712. Is this a bad opamp for the application or should I just try subbing the 100p cap with a bigger one?

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    1. For all those i've built, the OP275 simply works while others give out unexpected results. You should either get those or try to up the cap. Upping the cap will eat up some of the highs though...
      +m

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    2. If you have any 5532s, try those.
      +m

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  34. Tried to work with the cap, no success. Had to go up to 600pf or so, didn't hurt the tone all that much but 40% of the sweep is still unusable without the oscillation. Just turns to flubby nonsense. Gonna order some OP275 :D

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  35. Finally got myself some OP275 and fired it up - NOTHING. Went to measure the IC voltages and I'm getting 8v at Pin 1 so there's definitely something fishy going on here. Should be somewhere around 4v with a 9v supply, right? Maybe it's a misplaced / wrong value component.

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    Replies
    1. Yes and it's suspicious that pin 1 is right next to pin 8 which does have the 9V supply. If I were a gambling man I'd bet there is some sort of bridge under the IC, possible in the cut between pin 1 and 8. I can't see where else pin 1 would be getting anything like 8V from, unless it's an internal fault with the IC?

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    2. Exactly what I was thinking, gonna work from there. The voltage doesn't change when I change the opamp so either the circuit is eating them like bread or the other thing.. I'm guessing solder bridge :)

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  36. HOLD ON! Are the 1u caps supposed to be polarized? Am I noticing this just now? Oh good god that actually explains everything weird about this pedal. Oh boyeh.. So I might as well throw electrolytics in there 'cause I think I have some?

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    Replies
    1. No, I did this based on polyester caps which aren't polarised, but I showed the "-" symbol on there because someone asked which leg was which if they did use polarised caps. So use either.

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  37. Alright, so that's not the culprit. I actually tried electrolytics and it WORKED with AD712 for a while and I also got correct voltages at the IC. Started changing opamps and boom, same problems again. Only AD712 works to some degree. First half of the drive taper is fine, the other half is gated fuzzy nonsense. 4558D and OP275 give me absolutely nothing or just a silent fart. Well. back to the desk.. Also sometimes when I put the pedal on the sounds comes fading in after 5 seconds or so. Weird but I gues something is leaking voltage to the other half of the chip every now and then. I knifed all around already but didn't help.

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  38. First of, thanks to IvIark for this amazing site! The sweet honey overdrive is my first build and I've run into a problem.
    The bypass, switching and power-led are all working fine, but when I switch it on, the volume drops quite a bit, even with volume and gain maxed. Also it doesn't really sound distorted but more like a softer version of the clean signal with a bit of a cracking noise.
    Of the leds only D3 is blinking. I already tried replacing the D2 led but to no success. I also did quite a bit of scraping to make sure there are no bridges.
    Does anyone have an idea what the problem could be (or at least limit it to a certain part of the circuit?). Thanks!

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    Replies
    1. It could be anything from just a description, although often when a pedal is too quiet it can be down to something as simple as a cold solder joint somewhere. Measure the voltages between all IC pins and ground and we can see if that gives us any clues.

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    2. These are ic (LM833) values I measured:

      1. 5,90
      2. 4,15
      3. 3,05
      4. 0
      5. 2,15
      6. 4,32
      7. 4,32
      8. 8,12

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    3. They don't look too bad. 1 may be a bit high and 5 may be a bit low so I'd look around there first for any poor connections. Check all cuts are clean and no burrs left in them which may cause a bridge. If all that fails then you probably need to make a little audio probe so you can see where the signal is dropping out.

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    4. Thanks for your help, I've solved the problem! For anyone with similar symptoms, it turned out to be a bad connection to the 2K resistor.

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  39. I want to build this pedal but cannot seem to find any OP275 ICs around the Netherlands. Is it possible to use a different IC or does anyone know where I can find one in the netherlands?
    Thanks in advance!

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    Replies
    1. You could use any dual opamp, TL072, JRC4558, LM1458, NE5532 etc etc. But you should be able to get them easy enough from eBay.

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  40. Frustrating issue, I've got it working, but all of the sweep is bunched up at the start of the gain pot.

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  41. Just build one! second built for me and it sounds really really good^^.

    here's a picture :
    http://alborea.free.fr/Telechargements/diy/IMG_0346.JPG

    Hard to fit in 1590B with pots ands capacitors, so i've come out to this strange shape^^.

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    Replies
    1. Great stuff, thanks for the pics

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    2. Has anyone built this subbing the 13k7 and 2k61 for the nearest common values? If so, how did it work out?

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  42. I need a little help here. When it comes to LED's on the vero layout, should it be assumed that they are diffused?

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  43. In addition to my prior question. Would the Tayda LEDs be good enough? I have red clear ultras. I was not sure what specs to look for. Thanks in advance for any help.

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    Replies
    1. Most of the time you tend to see diffused LEDs in these, but it's the forward voltage that is important rather than the LED type. I would always recommend socketing these so you can try a few and just use the ones that sound best to your ears.

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  44. Just built this one as my first pedal project. Still working on the box but it bench tested great! Made my crappy practice actually sound nice. This is a sweet OD. Think I'm going to build the micro amp with tone control and box these together with a switch to select which goes first. Thanks for the great site and community. I can confirm that subbing the odd value resistors for the closest values works fine.

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  45. Been playing through this for a while and I find myself using it at the upper end if the gain sweep all of the time and occasionally wanting just a bit more dirt out of it. Can anyone suggest mods to get me 20-30% more gain/distortion? I already have red LEDs...

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    Replies
    1. Increase the Drive pot to 1M log

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  46. This comment has been removed by the author.

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    Replies
    1. http://tagboardeffects.blogspot.fi/2012/02/offboard-wiring.html'
      +m

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  47. This comment has been removed by the author.

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  48. This comment has been removed by the author.

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  49. Will this do the work for 1u capacitos? http://www.taydaelectronics.com/capacitors/monolithic-ceramic-capacitor/1uf-50v-multilayer-ceramic-capacitor.html

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  50. Build this succesfully, D2 D3 are blinking and D6 is not. I read from mirosol above that this is correct. The sound is really bright even if I turn the focus knob all the way down. Great OD pedal but its just too much treble for me.

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  51. If I wanted to make this like the new deluxe version (bass and treble pots) what resistors would I replace with pots?

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  52. Hi,

    just built this as a kit from BitsBox and it sounds pretty awesome. However, the Focus pot doesn't seem to do a great deal - if anything! Have i made a rookie error? It doesn't seem to get darker or brighter!

    Great Site by the way!!!

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  53. I found this OD a hit hard sounding. Nice feel and dynamics but not quite there yet. I used a red LED for D2 and green ones for D3 & D6 and replaced D4 with a BAT42 and D5 with a BAT41. This gives a more airy (less gravelly) sound and a softer feel. Try this if you feel the same about the stock version. Like it very much now!

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