Question about Marshall Amplification Marshall MG15CD 2-Channel 15-Watt Guitar Amp

Open Question

My Marshall MG15CD suddenly died, no sound coming from the speaker. checked the speaker and its fine. power supply is also okay since led indication is on. tried the cd input but with out success.

Posted by on

3 Suggested Answers

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

icansolve
  • 45 Answers

SOURCE: Marshall Amp Quit

According to the schematic, once the signal is initially amplified (also where the LED shows signal), the audio is sent to the send/return jacks (shown on pg3-C7). A quick test to see if audio exists at the insert point will require an insert cable. An insert cable can be a balanced 1/4" cable which splits out to two mono 1/4" connectors or a pair of RCA's. Connect one of the insert outputs to a console (if 1/4" cable) or a tape loop on a home stereo receiver (if send cable splits out to RCA's) and see if you've got sound when playing your guitar (with LED on the Marshall showing signal). If no sound, go to (A) below. If you have sound, go to (B) below.
(A) Ten pin connector labelled CON2 (shown on pg5-B1). Make sure connector is tightly seated and that the pins on the jack and the female connectors in the plug are clean and that good contact is being made.
(B) Twelve pin connector labelled CON1 (shown on pg5-B4). This is the DFX board - make sure this is tight and well seated.

According to the schematic there are voltages seen at several of the connection points previously mentioned. If you have a multimeter and are qualified and careful - check to make sure the voltages are present as shown.

If you're not qualified - meaning you have little or no experience - STOP and refer this repair to a qualified bench tech. They get paid to keep the magic smoke inside the amplifier. You may end up damaging things worse or even beyond repair or even damaging yourself.

Posted on Nov 13, 2013

jimbusse2003
  • 6 Answers

SOURCE: Marshall Amp Quit

Having repaired many marshalls, I find that the mechanical support for connectors, riser cards, and even the pots for the front panel can break the etch on the PCB. Remember these amps are subject to significant vibration so this kind of breakage where the vertical cards aren't supported or the pots don't interface to the front panel just right can happen pretty often. You can take a wooden popsickel stick or a wooden pencil and poke these interfaces. If you hear a crackel or sound, you can re-solder or perhaps run a jumper wire to fix the problem. Or you can rent a scope and track it down. I've used both methods in my past.

Posted on Jan 16, 2015

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

Marshall Amplification Marshall MG2FX Guitar Combo Amp power turns on but no sound


Hi!
At this point, I would just take it to a tech rather than poke around in it. It sounds like the power section is the problem as you have guessed, but without the technical knowledge you'd be shooting in the dark. That particular amp is right on the line of being expensive enough that would be worth repairing, but you might do just as wel to check Ebay for another used one.
Good Luck!

May 21, 2014 | Marshall Amplification Marshall MG2FX...

1 Answer

There is no sound coming out of my Marshall 100 watt tube amp head?


make sure the standby switch is operating correctly.Sounds like the power tube.

Dec 18, 2013 | Marshall Amplification Marshall JCM800...

1 Answer

My Marshall 250dfx has stopped working, there is power but nothing is coming out. No crackiling before, one min it was fine, the next it stopped.. Help!!


try another speaker or test the speakers on another amp. if the speakers are working then it's your amp . check out the output ic's. they maybe blown.

Dec 03, 2013 | Marshall Amplification Marshall MG30FX...

2 Answers

Marshall Amp Quit


According to the schematic, once the signal is initially amplified (also where the LED shows signal), the audio is sent to the send/return jacks (shown on pg3-C7). A quick test to see if audio exists at the insert point will require an insert cable. An insert cable can be a balanced 1/4" cable which splits out to two mono 1/4" connectors or a pair of RCA's. Connect one of the insert outputs to a console (if 1/4" cable) or a tape loop on a home stereo receiver (if send cable splits out to RCA's) and see if you've got sound when playing your guitar (with LED on the Marshall showing signal). If no sound, go to (A) below. If you have sound, go to (B) below.
(A) Ten pin connector labelled CON2 (shown on pg5-B1). Make sure connector is tightly seated and that the pins on the jack and the female connectors in the plug are clean and that good contact is being made.
(B) Twelve pin connector labelled CON1 (shown on pg5-B4). This is the DFX board - make sure this is tight and well seated.

According to the schematic there are voltages seen at several of the connection points previously mentioned. If you have a multimeter and are qualified and careful - check to make sure the voltages are present as shown.

If you're not qualified - meaning you have little or no experience - STOP and refer this repair to a qualified bench tech. They get paid to keep the magic smoke inside the amplifier. You may end up damaging things worse or even beyond repair or even damaging yourself.

Nov 12, 2013 | Marshall Amplification Marshall MG250DFX...

1 Answer

External Speaker hookup problem. I hooked up 2 external speakers (8 ohm, 160 watt) into my Marshall AVT 50 amp (tag on back says 4 ohm minimum). Everything worked fine, then I shut it down and now (next...


If you are competent with electronics, open it up and check the fuse(s). Especially if no lights come on. If you get voltage, then check the jacks you plugged into- they may have dirty interrupt contacts. When you plug the jack in- it opens those contacts that otherwise are closed making the circuit to the cabinet's built in speaker. Contact cleaner should clean them up if that is the issue.

While it is possible there is a power supply issue, you can see that quick with a voltmeter, it is not likely you did much more than blow a fuse.- very possible if you unplugged speakers with the amp operating..

If you think you killed it- you usually still get distorted noise.

Mar 29, 2012 | Marshall Amplification Music

2 Answers

Low volume on my marshall


I am very new here and don't know how to answer a question to a specific problem so I will write about the most common problems that I have had over the decades doing guitar amp repairs. If you find that your amp is extremely low in volume and then suddenly comes back to normal- check out the effects return [or power amp in] jack. Especially in Marshall amps-these corrode and your signal dies. If there is loud noise such as hissing and crackling with no guitar patch cord in the input jack- the input jack is likely at fault. They normally have switching contacts that ground part of the input circuit when the 1/4 inch male plug is disconnected. When this in is corroded or too weak to make normal contact, you can get these symptoms. If your amp is a solid state Marshall or Fender and there is a random buzzing sound with no guitar signal connected- hit the side of the amp and listen for the buzz to go away or become louder-if it does, this usually means that the connections are loose at the two large filter capacitors. In one or more Marshall amps, they use a filter circuit in the low voltage power supple for the preamp tubes. If you encounter a dead Marshall[the model escapes me now] remove the circuit board and resolder the four connections at the bottom of the bridge rectifier. If you have any other amplifier repair questions you can email me direct at computerlen@hotmail.com.

Nov 14, 2011 | Marshall Mg100dfx 100-Watt Combo Guitar...

1 Answer

My Marshall Haze 40 Amp started making a very loud humming noise after a couple hours of playing.I let it cool down,and turned it back on and the noise came back after a few minutes


may be one of the electrolytic capacitors in the power supply has become leaky...this is a common problem among amplifiers...so you let it cool down..then after a period of time the capacitor heats up and then causes the hum...the power supply caps filter out the 60 hertz ac line noise...which is probably the frequency of the sound it is making...this is a good indication of these caps going bad....another thing you can check is to see if the amp is properly grounded(eg: the ground pin on the plug is present) and that you dont have an open cord or input

Jul 10, 2011 | Marshall Amplification Marshall Haze 40...

1 Answer

Hi. I have a Marshal MG10CD amp. It was working fine, till a few days ago, when it suddenly stopped functioning. The amp gets power supply, as you can hear static when switched on, however, when the...


Check for a dry/cracked solder joint where the 1/4 inch phono input jack connects to the printed circuit board. Solid state Marshalls are renowned for this.

Feb 23, 2011 | Marshall MG10CD 10 Watt Combo Amplifier

1 Answer

Marshall MG50 DFX makes a squealing noise on power up


Yep, chalk that one up to poor design...The amplifiers are going out of balance during power up and down. Two seconds is pretty long... Try turning down the gain during power on and see if that affects it.

The pop on turning off is normal... None of these have speaker disconnecting hardware that is necessary for very high power amps. The biggies have hardware that checks amplifier is balanced before connecting the speakers and a relay also cuts the speakers immediatley on power down. As power goes up and down the circuitry comes to equilibrium and until it does, strange things happen.

I would investigate the CONDITION of the filter caps for the main power because if they age to a higher internal resistance that COULD cause the high freq oscillation on power up... Two seconds is MUCH too long.

There should also be some non-electrolytic caps NEAR the power output transistors to handle high frequency supply power bypassing.

Check the power bypasses that service the preamp stages. Look for pregnant electrolytic caps that have failed.

Ultimately, you MAY need an oscilloscope to isolate the high freq problem.

Jan 03, 2010 | Marshall Music

3 Answers

Marshall mg100hdfx loud fuzz and distortion and no guitar sound


Check your input (guitar signal).
Also, check your gain and volume levels.
Make sure that you have a reliable, steady, and clean power source as well.
If the problem persists, contact the store from which it was purchased. There are a lot of things that can go wrong internally with the cheaper Marshall models.

Jun 25, 2009 | Marshall MG100HDFX 100-Watt Amplifier Head

Not finding what you are looking for?
Marshall Amplification Marshall MG15CD 2-Channel 15-Watt Guitar Amp Logo

Related Topics:

96 people viewed this question

Ask a Question

Usually answered in minutes!

Top Marshall Amplification Music Experts

matt martin
matt martin

Level 3 Expert

1210 Answers

Vito Vacirca Jr.

Level 2 Expert

140 Answers

The Knight
The Knight

Level 3 Expert

74118 Answers

Are you a Marshall Amplification Music Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...