Tonepad Smallstone buzz

[LaceSensor]

Hi

Built up a tonepad Smallstone
It phases, seems to work as decribed. I havent boxed it, just rocking, and thropugh my test setup (basically some jacks hooked up with crocodile clips) I get a buzz with the phase. Im just going direct with the in out 9v and ground connections on the pcb, not via a footswitch, so I cant say if it buzzes in bypass.

However, I would say that it seems like a ground issue, right? But the ground wire is soldered fine. What can I check next? Its like 18 transistors and 5 ICs... should I swap these out one by one and see if one is dodgy? Surely it would phase if one of the semiconductors was an issue?

Any help interests me. For what its worth, the cheap test rig I use, works fine and normally silently for other testing of pedals...

thanks!

[twin1965]

Hi there. I would take the psu you are using out of the equation. I assume you are using one with your test rig? Use the cleanest source of dc - ie 9V battery and see if there is still buzzing. Use two in parallel to increase the current.

I had a noise issue with my Harbinger One and it was the psu. I tested it with a couple of 9V batteries and the problem went. I had to buy a new psu!

Hopefully its something as basic as this.

[LaceSensor]

same psu used for testing of my schumann PLL clone and its silent. Its a high quality Boss type..

Pretty sure its not that. but granted, I could try a battery...

[jimilee]

same psu used for testing of my schumann PLL clone and its silent. Its a high quality Boss type..

Pretty sure its not that. but granted, I could try a battery...

If you're rocking it outside the box with actual jacks,then you gotta ground both the audio jacks, otherwise you'll get that hum.

[LaceSensor]

same psu used for testing of my schumann PLL clone and its silent. Its a high quality Boss type..

Pretty sure its not that. but granted, I could try a battery...

If you're rocking it outside the box with actual jacks,then you gotta ground both the audio jacks, otherwise you'll get that hum.

Hi, I did ground the jacks.
this is a test setup I use for almost all builds, and the other one on my desk right now works great with no buzz. Therefore its not the hookups or the power supply.

Im wondering what else it can be...

thanks

[RobA]

Does it sound like ground hum? Is it high pitched or a low hum? Squeal like?

By buzz with the phase, do you mean that there is a buzz that is phased along with the signal or that it moves with the LFO?

Could it be a bad or noisy part?

One of the things I've noticed about OTA's is that if the balance between the signal strengths on their inputs gets a bit out they hiss like mad.

[LaceSensor]

Hey guys

thanks for all the input
I basically went and reflowed the whole pcb and now its working great.
I think it was a cold solder joint on one of the grounds

cheers and happy building