My Marshall started flaking out.

[Securb]

I play the hell out of my Marshall VS100 combo. I literally played the amp for 6 hours before practice and it was working perfectly. I took it to practice and intermittently it would make an almost chirping rhythmic sound. I thought is was my board at first but I unplugged from the amp and it would continue. I turned the amp on and off and it stopped. I played another song and the noise started up again. This went on all night.

My first though is to open it up dust bust the amp and clean all the contacts. If anyone has any other trouble shooting tips it would be helpful.

 

[DankStar]

Re: My Marshall started flaking out.

I always figured preamp tubes in hybrids didn't ever need changing, but right when I got my Randall hybrid, it was making funny noises. I switched the preamp tube out and all was good. Might be worth a shot.

 

[Securb]

Re: My Marshall started flaking out.

I will give that a shot I have a ton of preamp tubes I can swap out. The tube in there can't be more than 5 years old? maybe. Any advice is greatly appreciated.

 

[Gone_Shootin]

Re: My Marshall started flaking out.

I would try the tube swap first since you already have several laying around. If that doesn't work, I'd look into the power coming into the amp (maybe you need a power conditioner if you don't already run one), and any potential RF interference (maybe your amp needs some more shielding).

Where my band practices there is the same phenomenon with our PA. Sometimes it's a chirp like you described and other times it's a buzzy type of sound. We finally figured out it was RF coming from cell phones (usually an incoming text).

 

[BrianS.]

Re: My Marshall started flaking out.

I've had that cell-phone interference before...definitely worth looking into. For me, it only happened when my phone was on or very near my amp.

Cleaning contacts is always the first stop.

 

[Securb]

Re: My Marshall started flaking out.

I've had that cell-phone interference before...definitely worth looking into. For me, it only happened when my phone was on or very near my amp.

Cleaning contacts is always the first stop.

Where my band practices there is the same phenomenon with our PA. Sometimes it's a chirp like you described and other times it's a buzzy type of sound. We finally figured out it was RF coming from cell phones (usually an incoming text).

I had my cellphone sitting on top of the amp last night at practice and I never do that. That could be the culprit. I will plug it today and see what happens. If it is the phone I might still give the contacts a clean and check the tube for GP. If it is the phone I am going to feel like an idiot.

 

[DrNewcenstein]

Re: My Marshall started flaking out.

My phone stays in the case until I need a pizza or a cop.

 

[Securb]

Re: My Marshall started flaking out.

Weird I got a few beeps and some static when I first turned it on then it went away. The amp was in the garage overnight and it is super cold out there. I am going to leave it on for a while to see if I get and weird sounds out of it. So far it has been super quite. After a while I might throw my phone on top of the amp to see if that duplicates the problem.

 

[Securb]

Re: My Marshall started flaking out.

Thank you to the greatest brotherhood of musicians ever the SDUGF. I put the phone on the amp and it started flaking out again. Pulled it off and instant silence. I still might do some general maintenance to the amp - contacts, pot/switch cleaning and maybe a new preamp tube. But you guys got me right back on the road. Thanks again.