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Distortion pedal causing random jumps in volume??


yeeter

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Whenever I engage my Boss DS-1 (Modded) or my Ibanez SM7 (Not modded) my volume will jump randomly. Fender Strat> Dunlop cry baby> Behringer TU300> Ibanez SM7> Boss DS-1> Digitech Tone-driver> Tomsline Dumbler> Boss BF-2> TC electronic skysurfer> Fender Super Champ X2 Head> GearOne PA2400> two yamaha 15" speakers. None of my other pedals are doing this and I can see the peak LED on my mixer amp light up at random in coordination with a volume jump whenever I turn on either of the two pedals. I'm running the board off of a onespot with a daisy chain adapter. Please help.

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A few questions and some places to start...

Did this start after you added something [new/recently] to the signal chain?

Whatever that last unit was remove it and see if the issue is resolved.

Running multiple distortions can have unexpected results, so that is where I would start. They can cause 'cascade' effects which could manifest in a transient volume spike such as you are reporting. Do you have the Dumbler on when this happens?  May I suggest that you try taking the Tomsline Dumbler out of the signal chain? It is the least 'respectable' unit in the chain and so would be my first suspect.

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If it jumps when turned on and stays high its likely a gain staging issue.  If it randomly jumps yo and down when turned on I'd suspect something like a bum connector or possibly a dirty pot is causing the issue. Boss pedals are buffered and transistorized latch switching so its not likely to be a switch problem.  Maybe an issue with the DC power jack. The jack has a switch in it that switches between battery and wall wart but anything that happens when that pedal is on will occur when its off when it comes to power or connectors, just not as loud if the gain is cranked. 

 

The other possibility is over gain staging one pedal into another.  Drive pedals especially often have the ability to boost the output signal much louder then the bypassed signal.  Volume creep can begin to happen as soon as a drummer start slamming cymbals in your ears. It desensitizes your ear drums and you turn up the gain to sound normal.  Ever leave a guitar amp set up at the end of a session and simply turn it back on a few days later and notice its twice as loud as you think it needs to be?  It didn't sound that loud at the end of a session because youre ears were attenuating the loudness by the end of the session. 

You can easily over gain one pedal into another and force the next pedal in series to overload and do strange things.  What I typically do on long pedal chains is normalize my signal for each pedal to prevent the gain from stepping up too much causing big jumps when turned on and off.  You cant always trust your ears here either. 

You can download a free decibel/loudness meter for most cell phones for free. Turn it on in the room with the amp and start by setting your amp volume with no pedals tuned on. Then you can try each pedal solo and in combination with each other.  The decibel level shouldn't vary that much.  If you want a boost for leads start this process by turning your guitar down 1/4 to 1/3  then set your pedal gain staging up so its fairly even, then you can crank the volume up on the guitar for leads.  if you use a volume pedal at the beginning of the chain you can do it there if you want instead.  Gain pedals and compressors are the toughest to set because they give you a false perception of loudness. get used to using a db meter to set the actual loudness.  Your sound man and recording engineer will love you for this when your actual volume doesn't jump up or down every time you kick it on. 

 

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8 hours ago, 1001gear said:

Is it just a power spike or a more obtrusive jump(s)? How long has this been going on? Maybe you just need to clean stuff; pots, contacts, cable connections - solder joints or screws - whichever.

I don't know whether it is a power spike or not. All I know is that it just jumps in volume a lot for a second or two, then it goes back to normal.

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I didn't add anything new to the board itself. I had it taken apart for a church gig (my board has no case or velcro) and I had put it back together when I ran into this problem. I haven't had any other pedals turned on when this happens but the ds-1 started working normally again and so far the sm7 has been working normally.

[Edits]: It just did it again. ;-; | Engaging the other distortion pedals seems to make it stop happening or at least make the spikes as loud as everything else.

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There's a fair chance it's a bad connection between pedals. Set the board up at home as usual, turn it on and play while nudging the individuals pedals and cables etc with your foot - you'll quickly find where the fault lies, although it more than one connection is bad it can be a little harder to track down.

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Many inexpensive cables used connectors which are simply riveted together instead of being securely welded.  They combine layers of plastic for insulation between the metal and if you know anything about mechanics plastic and metal expand at different rates. Over time the contacts get loose and then make intermittent contacts.  Loosen the covers on the connectors and make sure there aren't any cats whiskers touching from hot to ground inside.  Also take the connector tops and sleeves and see if you can twist them. Dollars for donuts one or more is loose. 

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I have had transistors and caps create similar effects, in fact I just repaired a high end stereo that had a blown channel. It would make a weak sound till you turned it up then it would blast.  The sound quality was distorted however and I knew the cause was a blown transistor.  I had left the volume maxed when I turned it on and blew a middle stage transistor so only a half wave was coming through.  I thought for sure it was the power transistors because of the heavy AC hum so I changed them first but no soap.  When testing I saw a crack developing in the Transistor that was bad so it confirmed the readings I was getting. 

A foot pedal is much more likely to have a loose connection vs a bad part.  Pedals like the Boss are even polarity protected with a diode so the chance of zapping something with the wrong type of adaptor is nill. I would advise using a zero hum AC adaptor like a Dan Electro, Boss, or a brick that has the correct current levels.  I have seen those pedals plugged into a generic wall wart and had them create all kinds of hum due to their poor regulation and filtering.  The pin on the jack needs to fit the plug properly too.  Non standard 9V adaptors can have different sized barrels and make a poor DC contact. That plug has a switch that toggles from battery power to the adaptor power which is activated when the proper sized jack is plugged in.  A non standard DC jack may cause intermittent power and jump between wall power and battery if you have one in there. 

Likewise the input jack on most pedals is a 3 contact plug and the ground is completed to the circuit when you plug in. 

Loose PCB connections and cold solder joints are another possibility. Most circuit boards are wave soldered and occasionally a contact doesn't get properly joined.  Either the fl8ux fails to clean or the temp isn't right and you wind up with a cold solder joint. This is where the two contacts are touching but the two metals aren't atomically joined with heat.  Over time the lead in the solder exposed to oxygen tarnishes making it an intermittent contact.  When you increase power like when turning up the volume, the current jumps the oxidized contact and it works for awhile.  Then as it sits unpowered the tarnish comes back making it a bad contact again.  The only way to find these kinds of bad contacts is to inspect the board and reflow the solder joints on anything that looks suspicious.  In extreme cases a tech will signal trace the circuit using a buffered amplifier and listens to the input and output of components till he pinpoints the exact component that's failing.  using heat and cold can also contract and expand the circuits and reveal component failures. 

Something like that boss consists of a low cost op amp if I remember right and a couple of clipping diodes.  Its "extremely" rare when an op amp becomes intermittent.  If thay fail they don't magically fix themselves and start working again, so I don't believe you have any bad components based on your symptom.  Again, its most likely intermittent power or  signal flow and both of those can be narrowed down by swapping cables and power supplies.  Running it on a battery vs a wall wart of different cords.  Plus the Boss pedals are buffered. If it happens turned on it should happen buffered is its power or a cable. 

 

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