#1
Hi all,
Yes it is a marshall amp, but its a tiny MS-2. Anyway a while ago I posted about a problem I had but I found it difficult explaining exactly what the problem was. It basically makes a horrible wobbling crackling sound that doesn't sound good at all. Below is the link for a video I took where it shows how when you lower the voltage the noise gets less but it becomes distorted. Anyway its a cheap amp and I have lots of components lying around that I can swap in, but hopefully the video will give a better indication to what the problem is.

Thanks again and like I said the like is below


Marshall Ms 2 Amp Problem: https://youtu.be/jQJoHtL2dso
#3
get some deoxit d5....take it apart...clean the potentiometers(switches)


poof. amp will work.
#4
I know what pots are! But it sounds worse than just scratchy pots, they do seem to affect the sound, however the actual sound is odd. I will clean them though
#5
1. open trashcan
2. throw marshall in said trashcan
3. infinitely better sound
2002 PRS CE22
2013 G&L ASAT Deluxe
2009 Epiphone G-400 (SH-4)
Marshall JCM2000 DSL100
Krank 1980 Jr 20watt
Krank Rev 4x12 (eminence V12)
GFS Greenie/Digitech Bad Monkey
Morley Bad Horsie 2
MXR Smart Gate
#6
Ahahahah, that is a fair point. Although, I'd love to get it working, cus although not sounding amazing, its small and compact and a handy practice amp.

PS Have you got any genuine ideas or is it more expensive to repair it 😂😂
#7
Quote by EpicGuitarGuy13
Ahahahah, that is a fair point. Although, I'd love to get it working, cus although not sounding amazing, its small and compact and a handy practice amp.

PS Have you got any genuine ideas or is it more expensive to repair it 😂😂

unless you are good with electronics trouble shooting, That amp is not worth messing with IMO.

like said some good contact cleaner in the pots/jack is worth a try
2002 PRS CE22
2013 G&L ASAT Deluxe
2009 Epiphone G-400 (SH-4)
Marshall JCM2000 DSL100
Krank 1980 Jr 20watt
Krank Rev 4x12 (eminence V12)
GFS Greenie/Digitech Bad Monkey
Morley Bad Horsie 2
MXR Smart Gate
#8
Some questions about the amp to start with, I couldn't tell everything from the video but i'll walk through this to try and help.

Schematic is here: http://4.bp.blogspot.com/_VuFNYQK52XE/TAi_l6o-J7I/AAAAAAAAARk/3KRThCRfahA/s1600/MS_2+schematic.png

Was the OD on or off?

About how far down does the volume have to get before you lose the farting but get distortion.

Do you have a multimeter, if so can you check the following points on the circuit with the amp powered but no guitar plugged in. All voltages reference to ground

Juction of the OD capacitor to the other capacitor to its left
Junction of the capacitor to the left of the OD capacitor to the 180k resistor to its left
Pin 2 of the IC

Sorry that I don't have designators for these parts, but it should be possible to trace them on the PCB.
#9
Yeah I will try cleaning the pots as a first try. In answer to your question ( sorry I probably should have made it clearer!) The knob to change channel is on the far right - turned fully anti-clockwise is off, the middle is just "on" and the right is OD. So from 0:10 to 0:30 approx the OD is on and on and off near the end. I have a multimeter, but seeing as I can answer the other questions before I will. Basically you get the amp to roughly around the "2" mark without the wobbling sound, but unless the amp just sucks as it is (probably) the distortion sounds horrible and comparing it to videos of this amp, nothing like it really. The tone knob also somewhat effects it, but I suspect that that's because it is the tone knob and therefore effects what frequencies are more prominent.

And I will try testing with a multimeter later, although I may need to get some new probes!
Although I'm slightly confused about which capacitors you mean, because I can see the 180k resistor, but could you give me the value of it, for example 0.1,1 or 0.056 (I know you the area of the schematic to look)
Last edited by EpicGuitarGuy13 at Aug 20, 2015,
#10
have you run it with a battery?? does it still do it??....to me it sounds like its pick up interference (did you have a cellphone anywhere near it??)
#11
Okay before I started doing tests I did try running it with a battery and weirdly it worked! Obviously sounding as bad as it should have, but none the less it worked. So I'm guessing it's some fault from the how the the adapter connects into it. I can rest assure its not my adapter as ive tried different ones. So yeah I havent done those other tests yet, but out of curiousity would this just be a faulty component or something worse?