Stage Five Pedal Board issue | Page 2 | The Canadian Guitar Forum

Stage Five Pedal Board issue

Discussion in 'Effects Pedals, Strings and more' started by John Oughton, Sep 22, 2019.

  1. CathodeRay

    CathodeRay

    Joined:
    Jan 12, 2018
    Location:
    Toronto
    Maybe clarify how each 'device' in question can be pushed to it's limits.
    There are misconceptions re this and here's a chance to clear em up.

    If the device is a power SUPPLY, it can be pushed to its limits when ___.
    If the device REQUIRES power, it can be pushed to its limits when ___.
     
  2. mhammer

    mhammer

    Joined:
    Nov 30, 2007
    Location:
    Ottawa, Ontario
    My bad for not being clear enough.
    Think about fuses, the little glass kind. They work by passing current until such time as the heat generated by the current being pulled through exceeds the capacity of the wire/filament. The tiny conductor inside the fuse is selected for its ability to handle the heat produced by passing X amperes through it. As that amount of current is approached and exceeded, the fuse overheats and succumbs to the heat, burning out and creating an open circuit; a useful one, thankfully.
    A well-regulated power supply will include semiconductors that have their own fuse-like properties, and limits to current-handling capacity. Thankfully, many commercial pedals will include circuit adjustments to limit the amount of current they draw, such that the pedal will rarely be pulling more current than it can handle internally. So the risk tends to be more to the power supply.
    The upshot is that if a pedal (or combination thereof) draws more than 100ma on its own, and is being fed by a 3-pin regulator spec'd for handling up to 100ma, the regulator is likely going to get warm, possibly hot, and possibly too hot for its own good.

    I should add that what modulates/mediates the risk of heat damage is heat-dissipation opportunity.

    To illustrate, forum member zdogma has two Diamond Memory Lane pedals. One works fine, and the other worked but had an annoying whine, that he was hoping I could cure. After several exchanges with the good and responsive folks at Diamond, I was able to jog the memory of the tech support fellow, who said that in early runs of the pedal, a shipment of voltage-regulators they received for the Memory Lane had been found to have abnormally thin heat fins. The Memory Lane uses a trio of 1A-rated 3-pin regulators to derive several different voltages from a common wall supply. None of them is in physical contact with any other surface to conduct heat, and rely entirely on the metal fin to dissipate heat from the guts under the epoxy. The Diamond tech sent a pic of what the "bad" regulator might look like, and sure enough, one of the three looked exactly like the pic. What tipped him was that the whining would take about 5-10 minutes to start occurring. The unit fired up fine, but because the regulator could not dump enough heat fast enough (especially in a small closed space), after a short period of use the regulator would overheat and drift off-spec, leading to the "wrong" voltage and the whining. I replaced the existing one with another of the same part number, but having a heat fin with the normal thickness, and the problem disappeared.

    That's not a recipe for curing whining. Rather, it illustrates that overheating of portions of a power supply by taxing it don't necessarily result ONLY in damage, but can also result in a number of other sorts of issues, stemming from components not observing their best-case operating conditions.
     
    Last edited: Sep 23, 2019
  3. CathodeRay

    CathodeRay

    Joined:
    Jan 12, 2018
    Location:
    Toronto
    I just meant...

    If the device is a power SUPPLY, it can be pushed to its limits when it is asked to supply more current (mA) than it can produce.

    If the device REQUIRES power (e.g., a pedal) , it can be pushed to its limits when..
    -the supplied voltage (V) is too far above or below what's required.
    -the supplied current (mA) falls below the required current.
     
  4. mhammer

    mhammer

    Joined:
    Nov 30, 2007
    Location:
    Ottawa, Ontario
    Yes.
    Shorts in a variety of locations can result in a pedal drawing too much current. Depending on the design, if it's a thoughtful and cautious one, that may simply result in one or more components along the power path fry like fuses. I think we've seen many instances over the years of a resistor along the power path fried beyond readability. Because the resistor behaved like a fuse, that saves the life of everything else. Some designs, however, are a bit less anticipating of such catastrophic errors. Remember that there was a lengthy period when the majority of pedals either came with an on-board transformer and AC cord, or else were run off a battery. Many battery-operated pedals lacked a power jack for use with an adapter. The very idea that people would power a pedal with an outboard source that might be able to do damage to the pedal was still a long way off. So I'll forgive pedals from the '60s and '70s that did not include protection against power catastrophes.

    Most semiconductors (transistors, diodes, chips) used in contemporary pedals are either very tolerant of higher voltages (within reason), or else are accompanied by regulator circuits intended to step down whatever voltage is being fed to the pedal. So, whether you feed your chorus or flanger pedal 9, 12, 15 or 18V (though I'm not recommending this), the delay chip is unlikely to be receiving more than 5V because of an onboard 5V regulator. Of course, while the delay chip is protected in that manner, and the op-amps can likely "take it", that doesn't mean that any electrolytic caps included in the circuit are spec'd to handle higher voltages. There's a very good chance they are, but one needs to confirm it first, before proceeding. Powering a pedal that uses 16v-rated caps with a 15v supply is risking those caps being off-spec, and the pedal sounding bad for a variety of reasons. And while it is not a result of "stressing" anything, many pedals have biasing that is predicated on a particular supply voltage, and use of a different voltage is akin to mis-setting the bias.

    Providing insufficient current is unlikely to damage anything, but IS likely to result in poorer sound. I suppose the exception would be fuzz pedals where "starving" the circuit of current results in desirable glitchy sounds. I did this to a Jordan Bosstone clone, and a Fuzz-Face-like circuit, and feeding less current to the circuit yields some interesting results.
     
  5. vokey design

    vokey design Gold Member

    Joined:
    Oct 24, 2006
    Location:
    Not here
    Can you change your username to Wikipedia ;P
     
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  6. mhammer

    mhammer

    Joined:
    Nov 30, 2007
    Location:
    Ottawa, Ontario
    Then I'd have to put up with people editing me. For now, I like the control. For now. ;)
     
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  7. troyhead

    troyhead Gold Member

    Joined:
    May 23, 2014
    Location:
    KW, Ontario
    As damage is unlikely and it seems a bit unclear as to the exact current that is being provided, should @John Oughton just plug the Zoom into one of the DC jacks and see if it works with passable sound? Or is it possible that what works one day will crap out the next if the current is insufficient?
     
  8. High/Deaf

    High/Deaf Gold Member

    Joined:
    Aug 19, 2009
    Location:
    LM,BC,CAN
    If the OP wants it bad enough, use a small transformer to step up the 9V AC to 12V or so and then rectify and regulate that to 9V DC. That output has more than enough power behind it, but the complication would probably have me just use the pedal's supplied PS.
     
  9. knight_yyz

    knight_yyz Gold Member

    Joined:
    Mar 14, 2015
    Location:
    Hamilton, Ontario
    If the dc output is 100Ma per outlet as I stated earlier and the pedal needs more than that, it won't turn the pedal on. I have a T Rex Chameleon that has outputs @250Ma. My digitech trio needs 500Ma. The pedal will not work. But I could buy a current doubling cable that could plug into 2 of 250Ma outlets and give the pedal 500 Ma.....

    The OP could spend 10 bucks on the current doubling cable but if I am correct he will only have 200Ma. Still not enough if the recommended wart is 500Ma

    How old is the board?? Year 2000? Did they have pedals requiring more than 100Ma back then?
     
    Last edited: Sep 25, 2019
  10. knight_yyz

    knight_yyz Gold Member

    Joined:
    Mar 14, 2015
    Location:
    Hamilton, Ontario
  11. greco

    greco Gold Member

    Joined:
    Jul 15, 2007
    Location:
    Kitchener, Ontario
    What about these?
    Screen Shot 2019-09-25 at 12.42.59 PM.png
     
  12. knight_yyz

    knight_yyz Gold Member

    Joined:
    Mar 14, 2015
    Location:
    Hamilton, Ontario
    Still 100Ma. No room to print it in that little box
     
  13. knight_yyz

    knight_yyz Gold Member

    Joined:
    Mar 14, 2015
    Location:
    Hamilton, Ontario
    Reddit post from 4 years ago.....

    madcow104

    4y


    Assuming this is the board in question, you cant power any Strymon pedals with it.

    The page says "ALL of the DC outputs on the PS-55 are 100mA."

    Strymon pedals require 9v and varying levels of mA, but unless you have an OB1 (20mA), you need at least 250ma to power them, 300mA for the bigger ones (Mobius, Timeline, Big Sky)

    So long story short, looks like you cant do it without extra equipment, like a Current doubling cable, but even then you are still short of the proper power. Maybe if SKB makes a VAC to DC converter cable/rectifier you could use one of the VAC connections that provide 1.3a. but its not likely.

    You want to make sure your pedals (especially the digital ones) are powered properly, don't want to mess em up.
     

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