SOLVED Muzzle (Classic) crackle and fizziness

[ThatDude]

Hi all! I finished up a Muzzle (Classic) build this past weekend. The pedal seems to work as intended but I am getting some crackling and fizzy sounds when the input signal is crossing below the pedal’s threshold setting. This happens with the four cable or the two cable method. The noise happens even when the threshold is fairly low and you allow the input signal to sustain and decrease till it reaches the threshold. The noise only last about 2 seconds, or until the signal fully crosses below the pedal‘s threshold setting. Anyone else experience this and have any input on what the cause could be?

 

[ThatDude]

I am adding some photos in case they will help. Maybe I am just overlooking something.

 

[mkstewartesq]

I don’t have a solution for you but I’ll be interested in hearing what suggestions you get. I built a different PPCB noise gate (the Muffler) this weekend and noted in my build report that I was getting a similar fizzing and cracking when the sound transitioned below the threshold. I noted some things in my build that might or might not be responsible and solicited any feedback but didn’t get any. Perhaps hearing thoughts on whatever issue is ailing your build can you give me some thoughts on how to tackle mine.

Mike

 

[ThatDude]

I don’t have a solution for you but I’ll be interested in hearing what suggestions you get. I built a different PPCB noise gate (the Muffler) this weekend and noted in my build report that I was getting a similar fizzing and cracking when the sound transitioned below the threshold. I noted some things in my build that might or might not be responsible and solicited any feedback but didn’t get any. Perhaps hearing thoughts on whatever issue is ailing your build can you give me some thoughts on how to tackle mine.

Mike

I just checked out your build post. I like your Muffler! I also used a glitter brown enclosure from Tayda for my build. Funny, two separate gates and PCBs built by different people near the same date (I am guessing) with the same sonic curiosity. Maybe it’s the glitter brown enclosures haha. I don’t think all gates have the same fizz or crackling sound when they dancing near the threshold. I did an AB comparison to a friend’s ISP Decimator, and the Decimator did not make that sound, but maybe this is the way the Muzzle and Muffler work. Hoping someone can chime in and let us know if this is expected.

 

[benny_profane]

Do you have the enclosure itself grounded?

 

[ThatDude]

Do you have the enclosure itself grounded?

I believe I do. Through the footswitch making contact to the enclosure.

 

[benny_profane]

I believe I do. Through the footswitch making contact to the enclosure.

Unless you've run a wire connecting a ground point to the lock washer on the footswitch, the circuit ground will not connect to the enclosure via the footswitch. You may want to consider removing the powder coat from around one of the top I/O jacks and create contact with ground by running a wire from a ground lug and securing it between the jack and the enclosure when the jack is installed. Note that this is because the jacks are isolated, this extra step of creating ground connection is not necessary with non-isolated (i.e., metal frame) jacks.

 

[ThatDude]

Unless you've run a wire connecting a ground point to the lock washer on the footswitch, the circuit ground will not connect to the enclosure via the footswitch. You may want to consider removing the powder coat from around one of the top I/O jacks and create contact with ground by running a wire from a ground lug and securing it between the jack and the enclosure when the jack is installed. Note that this is because the jacks are isolated, this extra step of creating ground connection is not necessary with non-isolated (i.e., metal frame) jacks.

I just tested running a ground lead from the ground of one of the jacks to exposed metal enclosure and still had that noise. Going forward though I think I’ll switch to metal jacks to avoid the enclosure not being grounded. Thank you for the heads up about the isolated jacks. I hadn’t considered it.

I am suspecting that it is either an issue related to the THAT4301 I have, or maybe a capacitor issue since it is seems to be related to the signal oscillation near the threshold setting.

 

[Paradox916]

I wouldn’t go shot gunning parts yet but one thing I have noticed was people that have used the cheap ceramics in C14 and c16 along with something other than a MLCC in c11 have issues keep in mind correlation doesn’t denote causation in this case, but make me wonder, there has been more than a few people who say they have had issues with the 4305 retrofit module and there is always that possibility of manufacturing defects but I have built this pedal multiple times with both the 4301 and 4305 module and have had zero issues with ether.. and as @benny_profane had said grounding one of your jacks to chassis/enclosure is a good idea I prefer the input jack personally.

 

[ThatDude]

I wouldn’t go shot gunning parts yet but one thing I have noticed was people that have used the cheap ceramics in C14 and c16 along with something other than a MLCC in c11 have issues keep in mind correlation doesn’t denote causation in this case, but make me wonder, there has been more than a few people who say they have had issues with the 4305 retrofit module and there is always that possibility of manufacturing defects but I have built this pedal multiple times with both the 4301 and 4305 module and have had zero issues with ether.. and as @benny_profane had said grounding one of your jacks to chassis/enclosure is a good idea I prefer the input jack personally.

Thanks @Paradox916. I tested grounding the input jack after @benny_profane mentioned that I am not grounding the enclosure through the foot switch like I thought. I will also make sure to ground the enclosure for my builds going forward. I am still getting the noise though even when the enclosure was grounded during testing. Like you said, instead of shotgunning components, is there any value in trying a different LT1054 or TL072? I have some extra TL072s I can try swapping out also, but would need to get another LT1054.

I made a video of the sound I am getting from the pedal. I moved the threshold up higher than needed and I am playing softly to really bring the noise out.

IMG_1087

This is "IMG_1087" by Pat Gutty on Vimeo, the home for high quality videos and the people who love them.

vimeo.com

 

[Paradox916]

That is weird… taking a closer look at you pic I believe that TL072 might be a fake so swap that out and see what happens… would be an easy swap just to see.

 

[ThatDude]

That is weird… taking a closer look at you pic I believe that TL072 might be a fake so swap that out and see what happens… would be an easy swap just to see.

I got the TL072s in a pack of 12 of Amazon. I wouldn’t be surprised if they are fake. Haha I’ll try some of the possible solutions provided by the collective and report back if any of those things are the culprit. Thank you!

 

[Paradox916]

Don’t buy parts off of Amazon unless you know they are a legit source, they are almost certainly counterfeit

 

[ThatDude]

View attachment 69679

Don’t buy parts off of Amazon unless you know they are a legit source, they are almost certainly counterfeit

Well this is embarrassing. It looks like a counterfeit TL072 is to blame for the noise. I changed it out for a genuine TL072 from another pedal, and the crackle is gone. It also raised the threshold sensitivity significantly. Lesson learned, source parts from a reputable dealer. Thanks everyone who contributed to troubleshooting and @Paradox916 for spotting my bootleg IC!

 

[Paradox916]

Well this is embarrassing. It looks like a counterfeit TL072 is to blame for the noise. I changed it out for a genuine TL072 from another pedal, and the crackle is gone. It also raised the threshold sensitivity significantly. Lesson learned, source parts from a reputable dealer. Thanks everyone who contributed to troubleshooting and @Paradox916 for spotting my bootleg IC!

Glad it was an easy fix. It’s a great gate. And arguably the best DIY noise gate out there.