Help with MG15 amp buzz

[Back to Marshall]

Hello, I'm sure this has been discussed a million times, but this is probably a little different.
My MG 15 has a buzzing on the overdrive channel. Swapping guitars and cables doesn't help. Even tried a new Line 6 G30 wireless and still get the buzz. My sons bass amps don't buzz like this, and several years ago my Peavey Classic 100 tube head didn't buzz. I need to nip this in the bud, because I have a DSL 100 head on order, and don't want that buzzing. I bought a Furman SS-6B outlet strip and that didn't help.
Touching the strings on any guitar only helps a tiny bit. I can put the clean channel to full volume with no annoying sound, but turn on overdrive with the gain turned up, the buzz starts at volume 1!! Any help will be appreciated. I've already tried turning off lights, dehumidifier, etc. Also no dimmers in house.

 

[Whiteknuckle]

I don't know what they're called in english, but do you have an autonomous lawnmower droid?
I've read about alot of guys who get them, and suddenly have noise issues. They make a everything inside the guidewire basically a magnetic field.

 

[fitz]

Hello, I'm sure this has been discussed a million times, but this is probably a little different.
My MG 15 has a buzzing on the overdrive channel. Swapping guitars and cables doesn't help. Even tried a new Line 6 G30 wireless and still get the buzz. My sons bass amps don't buzz like this, and several years ago my Peavey Classic 100 tube head didn't buzz. I need to nip this in the bud, because I have a DSL 100 head on order, and don't want that buzzing. I bought a Furman SS-6B outlet strip and that didn't help.
Touching the strings on any guitar only helps a tiny bit. I can put the clean channel to full volume with no annoying sound, but turn on overdrive with the gain turned up, the buzz starts at volume 1!! Any help will be appreciated. I've already tried turning off lights, dehumidifier, etc. Also no dimmers in house.

I'm not sure about robot lawn mowers, but I get interference on some of my amps from LED light bulbs.
More buzz with more gain, and less when clean.
Try eliminating various electrical sources of possible interference.
Try moving the amp to different rooms and see if the buzz changes.
It might still be an amp problem, but eliminate external sources of the problem first.

 

[Back to Marshall]

Moving the amp hasn't helped. Meaning different rooms/circuits don't seem to change anything. There is a transformer on the pole in front of my house that my power lines come from, as well as an LED street light. But the buzzing is present during the day when street lights are off.
I just tried the amp on different circuits throughout the house. I got the least buzz in the basement near the electric panel. All the outlets I've tried the amp on are properly grounded, and I am using Sweetwater Excellines cables. This happens with a Fender/single guitar as well as my knock-off Les Paul. There are two outlets in the house in a circuit with any "Open Ground", but the only thing plugged into them are a light and a laptop computer and monitor, which are both in sleep mode most of the time.
There is virtually no buzz until I plug a guitar cable into the amp.

 

[Back to Marshall]

Could the amp need a better ground? Or are these MG amps prone to this, whereas mire expensive models are probably grounded better?

 

[fitz]

Could the amp need a better ground? Or are these MG amps prone to this, whereas mire expensive models are probably grounded better?

I wouldn't categorize it as an MG series issue, and it's hard to just say it's a grounding issue that more expensive models handle better.
Might just be an issue with that particular unit.
I had an MG15HCFX that gave me no problems.

 

[Back to Marshall]

Trying to post a video of issue.
Can anyone help? Can I forward it to someone?

 

[JohnH]

what if you plug in a guitar cable and short the jack tip to the barrel? usually this cuts out any hum coming in and you can see if any is generated within the amp itself.

 

[EADGBE]

Maybe try a different guitar lead/cable.

 

[Back to Marshall]

Give tried three guitars, different cables and different outlets. Other amps in the house don't buzz like this. Wonder if its possible to put a better ground in the amp? It also does this with my Line 6 G30 wireless.
Trying to attach a link to the video since I cant attach a video.

 

[fitz]

Trying to attach a link to the video since I cant attach a video.

Post to YT and paste link.
Starting to seem more like it's just a problem with that amp.
Is it new, or used?

 

[Back to Marshall]

They amp is new.

 

[fitz]

They amp is new.

Can you return for an exchange?
If it doesn't seem like external interference or bad power source, might just be something wrong with that particular amp.
It sucks, but sometimes they ship out a lemon.