Hiya everyone.

Is it safe to add a ground wire to a Micro Terror?

Here's the story. I have had the classic ground humming when not touching strings/metal on my guitar/pedalboard which I know is completely normal. However I've realized my Micro Terror has much much more hum/buzz than my other amps. Well I got to thinking that it was because the micro terror power supply doesn't have a ground prong.

So taped a ground wire from the handle on the MT and connected only the ground prong to a power strip, and poof no more humming at all. No ground hum at all, even while running a distortion/compressor/EQ and a few others. I played around for a good 20 mins and no issues. But I'm not sure if I lucked out and escaped a good shock or was this a good fix.

So what do you think? Would it be safe to wire a permanent ground to eliminate the hum? Or am I just going to get myself electrocuted?

Heres a picture of the wire
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Adding a ground won't get you electrocuted. Remember... the ground is there to provide a path for any voltage on the chassis. Since it's the closest path to ground, that's where it goes.

However, as an electronics tech... I would want to do a more professional job of adding that ground lug. What you have it work, but it's far from ideal.
that's odd i thought the whole reason for a ground lift was to eliminate
this problem .

he's adding a ground to eliminate noise which is total opposite .
Sometimes lifting the ground reduces noise, sometimes keeping the ground connected reduces noise. Depends on the wiring of the receptacle the amp is plugged into, and environmental factors may play a part as well.

On old, cheap amps with non-polarized line cords, sometimes inserting the plug a particular way around would affect the noise level, but this could be simply because there was usually a capacitor wired across the circuit/chassis ground and what would ideally be the neutral wire of the line cord. They were a holdover from old transformerless radios and were called "death caps" for good reason.
Last edited by Invader Jim at Jun 8, 2014,
Thanks for your responses! I feel safer now about it. I was pretty sure adding a ground wouldn't be dangerous. Yea the electrical tape was my test run. I'm planning on securing it to one of the screws on the back panel.

The power supply that came with is a laptop style one and only has two prongs. I wouldn't know how to go about adding a ground to those. That would sure be more convenient.
Quote by Someone5698

The power supply that came with is a laptop style one and only has two prongs.

if you bought it used they changed the original supply for more pwr

they talk about it on orange forums
Last edited by gocosfs at Jun 8, 2014,
My micro terror was supplied new without a power supply (at s discount)
I purchased a 15v 2amp wall wart from Jaycar which worked but I was experiencing the horrible earth buzzing discussed here.
On above advice I connected a copper wire to the earth pin of a 240v power plug and plugged it into my power board with the other end screwed to the metal handle of the micro terror. Booya! No buzz. Problem eliminated.
Interestingly when I attached the earth cable to the micro chassis it made no difference. I'm assuming the decent paint job on the micro was insulating the chassis from the earth wire rendering it inaffective.

Thanks all for your wisdom
Someone5698 Hey man, I know this thread is a year old, but I just got a second hand Tiny Terror and I'm having the same problem you describe. Lood buzz when the instrument cable is connected, and even when the instrument is not plugged. However when I touch the metal handle of the TT with the connected instrument cable, sudden silence.
If it worked for you, I'd like to know how you built that ground wire, and if I could have a diagram or pictures of your installation ?

Thanks a lot.