A Guitar Amp Question...believe it or not.

[Mikeyd74]

I have resorted to coming here for advice about a guitar amp of mine. It seems that the guitar community cannot seem to get it's collective **** together and form a decent forum. Kudos to all of us bass players at Talkbass!
Anyway,
Last night I was coming up with some simple chord progressions on my guitar for a bass part of mine and I noticed that there was a light coming from inside the amp itself. I never noticed it before, I was pretty much playing in the dark. The light was only visible from around the button that switches channels between clean and dirty. I switched to the clean channel and it was still doing it.
The light is white and starts to turn red as I hit the strings harder. As far as I know it's solid state. Just wondering if any of you know what I'm looking at before I open up the amp and take a peak. I'm just concerned about a potential fire.
The amp in question is the Marshall Microstack MG15MSll.


Any help would be greatly appreciated!

[98dvl]

Inside the amp (head) or cab (speakers)?

If it's coming from the cab, it's most likely a light bulb.

They're put in there to keep your speakers from blowing.

You're most likely driving the cab too hard.

If it's from inside the head, probably a clipping light? If so you're pushing the head too much (sending to strong of a signal from your guitar/pedal chain).

[edit]

Just re-read your post, sounds like the clipping light...

Turn down the output on your guitar, or turn down the input volume on the amp...

[69nites]

+1 on the clipping light

[Mikeyd74]

It's coming from inside the amp head itself. There is no LED indicator to tell you if you are clipping or not. If there is one inside the head why would't they just make a spot for it on the face plate of the head? Weird.
I was using my ESP with active pups last night so I just plugged in my passive strat and it's doing the same thing whether the input is high or low. I'm hoping it's just an internal function of the amp.
I might crack it open and take a peek later just to make sure.
Thanks for the help though.

[theshadow2001]

Really your best bet is to email marshall or check the marshall forusm.

[The Golden Boy]

Originally Posted by Mikeyd74

I have resorted to coming here for advice about a guitar amp of mine. It seems that the guitar community cannot seem to get it's collective **** together and form a decent forum. Kudos to all of us bass players at Talkbass!

There's plenty of awesome guitar forums.

Can't help you with that light thing inside your head. Do you do work on amps at all? Might want to pull the chassis and see what's going on in there-

I found this on the NAMM release for the unit:

Like all amps in the MG Series, the MG15MSII incorporates Marshall's proprietary FDD (Frequency Dependent Damping) circuitry, which is controlled via an on/off switch on the front panel. FDD mimics the interaction of an all-tube amp's power stage with the loudspeakers it is driving and, in so doing, emulates tube amp feel and sound.

I'd check that first.

If you're hitting it harder and the light changes colors- and the amp is designed to simulate "sag" (change it's response to the intensity of the input signal), it sounds like it might be related to that.

[PunkRocker33133]

Sell it and buy a better amp? I was never too impressed with the MG series and you can get a blackheart 5 watt tube half stack for 250 USD that sounds so much better

[Mikeyd74]

I already sent an email to Marshall and I've been playing the "waiting game." I'm hoping that "The Golden Boy" is right. As for getting another amp, no way, I love this amp! Such a huge sound for such a small amp. Plus it's great for recording purposes!