Home Forums General DIY Pedal Discussion Capt. Munch Initial Test

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  • #10413
    Cybercow
    Moderator

    RickMurphy – there is no “white powder”. What you are seeing is the result of the audio probe tip scratching the left-over flux (residue) from soldering.

    Also, to perfectly honest with a sincere intent towards constructive critique, your soldering technique appears to be quite inconsistent. Some solder points are clearly supplied with solder, while other solder points appear to have NOT been heated enough and the solder just blobbed up around the leads\wires poking thru the PCB. I suggest reflowing the solder, with possibly a touch of additional flux on the solder joints. For instance, note the lack of solder around the diode leads (diodes D3 & D4) on the component side of the PCB.

    Once you’ve reflowed the solder, you can use an old toothbrush and rubbing alcohol to remove any excess flux from the solder-side of the PCB. Just let it dry thoroughly before firing it back up after the alcohol cleaning.

    Regarding the volume when the clipping diodes are engaged: clipping diodes will limit the signal to a maximum of the Fvd of the clipping diodes. Silicon typically has a Vfd of 0.78v to about 2.5v – depending on what diodes are used. (1N914 are at about 0.78v and some LEDs have a Fvd anywhere from 0.9v to 2.5v depending on the specific diode used. So when the clipping diode switch is in the center position, there should be no clipping diode engaged. (At least, based on the schematic.)

    #10496
    rickmurphy
    Participant

    Thanks much for your constructive critique. I am new to soldering and I look forward to learning from your suggestions.

    While I followed the guides in using a fine conical tip, I found that the tip did not heat well unless I touched it 1/8 of an inch or so above the pad, then I struggled to get the solder down to the pad. I have a narrow chisel tip that seems to heat the components better than the fine conical tip. Can I use that instead?

    I plan to ask a few follow up questions about the clipping diodes after I re-flow the solder and cleaned the board.

    Thanks again for your help.

    #10497
    Barry
    Keymaster

    Do you tin the tip after every 5 to 10 solder points and clean the tip using a metal scouring pad etc between every couple? The tip should be nice and shiny for even heat distribution.

    I have been using the same exact conical tip now (like in the photo) for 5 years and it still looks great.

    You can tin with solder but I like the stuff below and it lasts forever.

     

     

    Heat the pad and component lead simultaneously for a few seconds (longer with ground pads) before applying solder to the pad and tip.

    #10551
    rickmurphy
    Participant

    Barry, thank you for taking the time to provide this advice.

    Yes. I am very disciplined in cleaning the tip. I have a can of tin and use it on the tip.

    What I did wrong based on the diagram was to touch the solder to the tip-side of the work rather than touch the other side. What I observed was the pad had not sufficiently heated and the solder did not flow from the tip to the pad.

    When I reflow the solder I will experiment with 1) a narrow chisel tip which may provide a larger surface area to transfer more heat to the pad; and 2) increasing the nominal heat displayed on the soldering station from 750 to 850. The nominal heat on the display may not be accurate.

    Thanks again for your advice. I hope to report back later in the week.

    rick

     

    #11301
    rickmurphy
    Participant

    Thanks for your patience on this.

    After some delay I have now re-flowed the solder joints. I still need to validate the build.

    Currently, the Capt Munch produces about a 25dB increase in volume with the volume pot fully clockwise. Is that the expected behavior?

    However it is still well below the volume of the reference pedal. My reference pedal produces about a 35dB increase in volume at one o’clock.

    There’s quite a bit more I could increase the reference pedal, but at 1 o’clock it is already producing about 10dB more than the Capt Munch.

    My measures are not very scientific. What’s the best was to measure the output of the Capt Munch?

    #11310
    Barry
    Keymaster

    What reference pedal are you comparing to?

    Are you trying to produce a copy of something else? If that is the case component choices and their applicable tolerance can make audible differences. Likewise component values are not necessarily going to be exactly identical in regards to exact output. The more the Gain is increased the more Output.

    That said a properly working circuit (which has been around for about 11 years now) produces much more volume than “Bypass” which is well over Unity Gain. That is all that is typically needed. Not all pedals produce the exact same output at the exact same spot on the potentiometer. A resistor value change can also affect the available output of a circuit.

    The questions I have since the last post is only talking about Volume now:

    Does it sound good?

    Are you getting distortion and tone adjustment?

    Is there a reason you need more than 25dB over Unity Gain?

    This way we are not chasing tails to figure out multiple potential build issues. If Volume is your only issue then we can probably rule out things like wiring, solder joints and much more and perhaps just focus on your Volume concern.

     

    #11320
    rickmurphy
    Participant

    Thanks for getting back to me Barry.

    Here are my answers to your questions :

    The reference pedal is a SuperCrunchboxV2. I did not name the “reference pedal” to comply with the prohibition of discussion clones on the forum.

    No, I am not trying to produce a copy of something else. I am trying to verify that I have properly completed the Pedal Parts and Kits Capt Munch Kit. I understand about component choices. In my case the choices were made for me by Pedal Parts and Kits. I also understand the gain dependency. During my test Gain was also rotated fully clockwise.

    The 25dB increase in volume seems to satisfy the requirement that “a properly working circuit […] produces much more volume than Bypass”, but the ambiguity of the requirement does not allow me to verify that I have properly completed the Pedal Parts and Kits Capt Munch Kit.

    No, it does not “sound good”, but that is subjective. More to the point the Capt Munch Kit doesn’t sound like the SuperCrunchBox. I will stipulate that no claims were made that they would sound the same or alike.

    Yes. There is distortion and tone adjustment.

    If the Pedal Parts and Kits Capt Munch Kit intended to provide more than 25dB, then yes I would need more. I am just trying to validate that I have completed the kit correctly.

    Thanks again for the time you spend answering my questions.

     

     

    #11321
    Barry
    Keymaster

    Okay this all makes more sense now. We are absolutely dealing in Apples and Oranges.

    Our Capt. Munch is based on the original CrunchBoxPedal (Pre-V2 Basic design single Passive Tone only) A look at the schematic or just the BOM listing parts indicates this. It also happens to be one of the first three circuits we ever offered more than 10 years ago.

    Additionally the SuperCrunchboxV2 (2017) cannot even be compared with their original V2. Here is why…

    The SuperCrunchBoxV2 is not the same circuit as their original Crunchbox or even their Crunchbox V2 which is still (all Passive Tone controls) What makes the Super, Super is It contains a 3 Band Active EQ (Baxandall) section much like our Tone TwEQ board which is an additional add-on to the old circuit. The Passive (cut only) tone control on their original design is now called their Presence control. Because the add-on Baxandall EQ section is entirely Active that would account for all of your Volume differences. I would not expect either of these circuits to perform the same.

    Doing a bit of Google shows this:

    CrunchBoxPedal original (compare it to our version):

    Note: You could add a Tone TwEQ and it would give you more Volume and lots of Tone control.

    While I could not find a schematic of their 2017SuperCrunchboxV2 if you go to their site this is what they say about it:

    “The original tone control has now been relabeled PRESENCE. the most exciting addition to the Super Crunch Box is the new 3 BAND EQ. This is truly a unique design, utilizing an active design, 3 isolated bands offering +/- 12db of cut and boost”

    Also this image shows the Active Tone Control layout:

    So the result is indeed Apples and Oranges at their most extreme even if you compare their original products.

     

    That said if you up-load a demo I would be glad to listen to see if I think there is something wrong with the circuit based on a demo. It is a simple circuit and provides a smooth tube like distortion that should sound good on any amp. It however is nothing like their current Super model.

    Finally here are two unique audio demos using our Cap’t Munch exclusively:

    I made this one  <– This demo is just made with an iPhone so it is very transparent.

    T-Diddy made this one

    I hope all of that helps.

    Final thought:  If you really want a circuit that is more comparable to the SCBV2 then try the Cranky Charles with similar topography and 3 Band Active EQ.

    #11324
    Cybercow
    Moderator

    rickmurphy – Doing a build and initially concealing the fact that it being compared to another build is not only an apples to oranges scenario, it had us all chasing our own tails trying figure out what’s up.

    #11325
    rickmurphy
    Participant

    Barry, thanks again for the time you spend answering my questions.

    Recall my following statements :

    RM> No, I am not trying to produce a copy of something else. I am trying to verify that I have properly completed the Pedal Parts and Kits Capt Munch Kit.

    RM> I am just trying to validate that I have completed the kit correctly.

    Thanks for your offer to listen to a demo, but that seems subjective as well.

    Notwithstanding the differences between the reference pedal and the Capt Munch circuit, given the components in the Pedal Parts and Kits Capt Munch Kit, there must be some objective measurements that can be performed to validate whether the kit has been built correctly, right?

    What are those measurements, so I can validate that I have built the kit correctly?

    #11326
    rickmurphy
    Participant

    Cow,

    The issue at hand is what objective measures can be performed against the kit given the known components so I can validate that given my limited experience and knowledge that I built it correctly. What are those objective measures?

    While I appreciate Barry’s offer, a demo would likely be subjective. Validation of a completed kit would be an assessment against objective measures.

    #11327
    Barry
    Keymaster

    You can list the voltages of the IC to make sure everything is being powered correctly.

    Follow Pin order as shown in a datasheet (Google Chip name and the word Datasheet).

    Billy and the rest of us already went over your entire build and verified all components visually and since this was a kit I feel extra secure in that everything is correct. There is not much else to check from our end.

    Also an Audio excerpt would indeed be helpful since I can hear if something is obviously wrong or right. I only used an iPhone to record the one I made for you above and sounds like it but I can easily tell if the circuit sounds correct.

    If I say it sounds right and you hate it then it is subjective. (Case Closed) If I hear something wrong then it isn’t.

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