Top 20 Marshall Amplification Marshall MG15FX Guitar Combo Amplifier - 8 Inch, 15 Watts Questions & Answers

you may have a loose connection

Have you checked a different cable?. Also, when you plug in the unit, there should be a "pop" if everything is turned on. If there isn't, the connection is bad someplace.

Mixer uses balanced outputs, this unit does not... Also ground loops can be a problem. Make sure this and the mixer are BOTH powered from the same receptacle. The next problem is that the level of the mixer is MUCH too high for an amp designed to recieve guitar signals if you are sending a mixer into this. It is NOT clear how you are connecting this to a mixer... IF you happen to be trying to send signals from this to a mixer, either use a mic OR use a Direct Input box. You should tell us exactly how you are connecting this to the mixer since there are MANY ways, and most do not make sense.

check to see if your fuses are blown should be an easy fix

https://www.dropbox.com/s/6spu98r39t2wvcr/Marshall%20G30RCD%20Schematic.pdf

Most likely cause for this is an intermittent potentiometer. Check to see if any of them are mechanically loose as this is a sign that they have been damaged and could have cracked the wiper surface inside the pot causing this problem. Alternatively, any switch that controls any gain setting could also be intermittent or dirty. Gain of the amplifier should be stable, but is controlled by the feedback and signal injection at the pots so that is where to look first. Good luck, as intermittent problems are tricky, but sometimes better than no function at all which can be more costly.

Hi. Doesn't look like it as the speaker is a 4 ohm one and the head needs at least 8 ohm as far as I can see.

What type of Marshall, please? First of all, control the fuse and let me know.

clean switch connections

Make sure speaker cable works and is connected then check fuses. If it has a master volume, make sure it's turned up.

Does anything happen while you turn the knobs on the amp? I had a similar problem with a yamaha amp. It turned out a couple of knobs went bad. Soldered new pots and it works fine for me now.

http://www.manualslib.com/brand/marshall-amplification/amplifier.html Scroll down alphabetically.

Some Marshall serial numbers might tell you the year your 3005 was made, Marshall stamped the different years of the micro's in different spots, your number could either be on the back metal plate stamped right above the AC power cable port, or barely visible on the front gold plate above the power switch just under the Tolex, at least that's where my 1988 3005's serial number is stamped. But it should have one on it somewhere, could even be inside the head too, my sis plays and has an old 1977 50watt tube head with an interior serial number. I've been a huge fan of the Micro stacks since they came out in the mid-80's. I believe the 3005's were only produced from 1985 or so till around 1988 or 89 in Black, White, Red, Orange, Blue, Purple, and Grey, a Camo Tolex was a custom option as far as I remember. 1987 was Marshall's Silver 25th Anniversary, so a Silver Tolex Jubilee edition was made that year only. Than the newer MG15-II's were made from around 2004 till 2010 along with the Zakk Wylde signature series micro stack,. And now they make the newer MGD's since 2010, I just tried one last week at my local guitar shop, I liked it a lot, it's very different sounding than my old 1988 or my 2009 micro's and has a few built in effects which weren't great, but not that bad at all, I have a 1988 3005 stack that came with Celestion G-10's in the cabs and an MG15-II series micro stacks, that one came with some no name 10's, but believe it or not they sound better than the G-10's! Mine are all in black, I have been after an original micro stack in white for many years.Did your old 1x10 cabs come with Celestions too?

First check the preamp valve in that curcuit

Open the cabinet (remove back panel). Either a wire came loose or one of those 2 speakers is blown.

https://www.manualslib.com/manual/99237/Marshall-Amplification-Mg15msii.html

No, the ATV50 head is rated for 4 ohms total. Using both 4 ohm cabinets at once will fry your amp. Your only option would be to rewire your cabs internally to 16 ohms each by connecting the speakers in parallel, but that would cut your amp's power in half.

No, the ATV50 head is rated for 4 ohms total. Using both 4 ohm cabinets at once will fry your amp.

It may be dirty, spray it with contact cleaner, and also make sure the retaining nut is tight and solder connections are sound.If the jack is actually damaged, you can get suitable replacements from http://www.tubesandmore.com Digikey and mouser have them too, but the price is about the same with less searching. Also check to make sure any connectors into the preamp are snug and secure as well.