Build Your Own Clone Message Board

Hi Guys,
I built the Rams Head version from here, and it works and sounds great, but there is a hum I get that is too high for my noise gate to process.
It's there with either battery or power supply, and its more of a low-frequency hum than a buzz. I haven't measured it specifically, but I have the test equipment to do so, so maybe I'll do that sometime.

It's not unusable as-is, its not terribly loud unless you're not playing anything, but compared to my other tube overdrive circuits I use, its much louder.

I've searched the forums and haven't found any similar reports. Is this typical?

Did you ground the Sleeve on the output jack? Do the controls effect the hum at all?

I have heard of people getting some hum or noise with a cold solder joint. Maybe do a quick reflow.

Thanks for the reply. It's been a little while since I've opened up (been busy playing).
I just wanted to know if its typical to have that sort of hum noise before I tear into it more. Like I said, it's not unusable, but there's no way I can leave it enabled while I'm not playing or during a pause in a song.

With 4 cascaded transistor gain stages, the LB will tend to be noisier than many other "dirt boxes". But a noise gate should take care of it (I run mine with a Boss NS-2, and it's very quiet), so that makes me think something else is going on. What's the rest of your signal chain, from guitar to amp?

There's been at least one case where a member had a noise issue that turned out to be due to grounding the PCB to the output jack. This connection creates a ground loop because the jack is already grounded by being in contact with the enclosure. When the person removed this connection it corrected the noise issue they were having.

If that doesn't fix the problem I'm willing to bet that it's an issue with your build somewhere. The LB is very quiet IMO when you take into consideration the amount of gain the circuit has.

+1! Amazingly quiet, given its gain.