Marshall Audio Players & Recorders - Recent Questions, Troubleshooting & Support

Retired sound engineer here, so you're in luck. First, it depends what you're trying to do. 1. If you just want computer audio to come out of the Marshall, just get a 3.5mm male to 1/4" male cable. 2. Usually you wouldn't plug into the earphone output, but the audio line output on the back of your computer (usually green). 3. If you want the computer to create effects in real time on your guitar, instead of plugging the guitar directly into the Marshall, get a second 3.5mm to 1/4" cable and plug the guitar into the computer audio input (usually a blue jack in the back of your computer). Best of luck!

Not certain what you mean by "cable music" but if works normally on the other, that shows there is a connection problem. Does it connect to this source via a cable? If so I suggest you replace it.

I had to recently repair a Kilburn and couldn't find any schematics. However, if you read my post below it may help you get yours fix. I feel there might be common failures in these 2 models: Marshall Kilburn bad caps WARNING: VERY LONG POST (cannot upload pics due to size) One of my coworkers asked me the other day if I could take a look at his Marshall Kilburn speaker to figure out why there's no audio coming out at all. The speaker would charge the battery, turn on, select the source input and even connect to bluetooth, but absolutely no audio playback whether connected with audio cable or bluetooth. The speaker was not exposed to the elements, it simply decided one day when he turned it on to not play any audio. I disconnected the AC power and the battery and opened up the unit to inspect the board for obvious signs: burnt components, dislodged connectors etc., but found nothing unusual. I had a hunch that something went wrong on the audio part of the board, but being unable to find the schematic, I started with the data sheet of its audio "brain" - U10. This chip is NTP8230 and you can get the data sheet here: http://www.zpxic.com/manual/NTP8230_icpdf[1].pdf copy the address and paste it in your browser. This was enough to get me started on checking the voltages ( I reconnected the battery ONLY), which turned out to be ALL correct and again no signs of damaged components. I disconnected all the connectors and removed the board from the metal back plate to be able to have a closer look under the microscope. This was the EUREKA moment. While the normal inspection could find anything wrong, a closer look found tiny traces of corrosion in certain spots on the board-see pics below: 5940, 5954, 5955, 5959 Since the resistor R95 looked quite corroded, I started poking around (literally) the black compound covering the other half of it. 5945, 5946,5952 I have manufactured my own tool for the job: soldered a sewing needle to an old multimeter probe. As I was poking the black resin, I could see some oily liquid seeping from underneath. As I EXTREMELY gently poked and picked chunks of black resin, I had the deja-vu moment. This was the BREAKTHROUGH ! Just when we thought the bad caps nightmare that plagued the industry for more than a decade was over, the curse of the leaky caps strikes again. Now the culprits are the cheap CHENGX electrolytic caps used on this high end (?) speaker. The electronics companies never really learned the lesson ? It has become very obvious what I was dealing with: corrosion damage incurred by the electrolyte leaked from the caps and nicely concealed by the black compound surrounding various components. From this point on, you are about to embark on a long and tedious journey and I cannot emphasize enough about how gentle and careful you have to poke and pick the compound to expose all the affected areas , without damaging traces and the surface mount components hidden under the compound. Do not cut corners ! After all, cutting corners created this mess in the first place: clear nicely all the affected areas. The area around the AC input was not affected ( no caps) and didn't need to remove the compound. The next step was to neutralize the corrosive liquid and clean up the mess. I always had the best results with de-ionized (or distilled) water to clean the corrosion and the residue. Use a little semi-stiff artist brush for local clean-up, DO NOT submerge the board! Once you are happy with the outcome, finish the cleaning job with 98% IPA (isoprop alcohol). This one you should apply freely making sure it penetrates under the big components as well. You can do this twice if you feel like it. Th IPA will remove other residue and most importantly will remove the de-ionized water used before. Let the board dry nicely and at that point you can start assessing the damage incurred by the corrosion. 5960,5961,5962,5963 In my case, the resistors R95 and R97 suffered the most damage: 5952 R95 was completely corroded and came off, R97 looked a bit better but still had to be replaced. Luckily enough the pads were still ok, once I scraped off the oxide. Luckily I had exact replacements for the two 100 Ohms resistors and these are the results: 5964 So, were these two the root cause of my initial issue? Short answer: YES ! Long answer: both resistors were open circuit. Tracing the pads I found them leading to our audio ic U10, pins 8 and 9. Looking at the NTP8230 data sheet, pins 8 and 9 are SDA and SCL. Now it all make sense ! These 2 pins are the i2c communication lines with the rest of the board and they were disconnected (open). Our beloved audio chip is in i2c slave mode and although it was powered on, it couldn't talk to the master. So it would just sit there, doing nothing. Hence no audio output ! Reconnected all (except for AC power) and gave it a try. Wow, I soon understood why my coworker wanted this puppy repaired. The sweet sound coming out of this speaker was the prize of my hard labour :) Sooo, is the repair done ? Yes and no. Well, the leaking bad caps became worse and they will probably leak some more or dry out completely. In order to properly finalize the repair, all the electrolytic caps should be replaced with proper ones and reapply some compound (RTV maybe?) to prevent vibration damage ( it is a speaker enclosure, remember?). Luckily, digikey and mouser offer a very good choice of quality caps (Nichicon, Panasonic, ChemiCon) which will not break the bank either. Totally worth it (20-30 bucks total). All you have to do is to cross reference the original cap specs to make sure you get the correct replacement caps. CHENGX provides a spec table for their caps which is not the best technical sheet but it is better than nothing: http://www.bentex.com.hk/catalog/capacitors/electrolytic/index.shtml (copy and paste in your browser) Now, it would be REALLY nice if any expert out there would pitch in and provide a tested and proven direct replacement info for the caps replacement. It is time for me to move on to other projects, but I will still be lurking around for a while in case you have any questions regarding the above. Good luck everyone and happy fixing !

Hi Lisa. I had to recently repair a Kilburn and couldn't find any schematics. However, if you read my post below it may help you get yours fix. I feel there might be common failures in these 2 models: Marshall Kilburn bad caps WARNING: VERY LONG POST (cannot upload pics due to size) One of my coworkers asked me the other day if I could take a look at his Marshall Kilburn speaker to figure out why there's no audio coming out at all. The speaker would charge the battery, turn on, select the source input and even connect to bluetooth, but absolutely no audio playback whether connected with audio cable or bluetooth. The speaker was not exposed to the elements, it simply decided one day when he turned it on to not play any audio. I disconnected the AC power and the battery and opened up the unit to inspect the board for obvious signs: burnt components, dislodged connectors etc., but found nothing unusual. I had a hunch that something went wrong on the audio part of the board, but being unable to find the schematic, I started with the data sheet of its audio "brain" - U10. This chip is NTP8230 and you can get the data sheet here: http://www.zpxic.com/manual/NTP8230_icpdf[1].pdf copy the address and paste it in your browser. This was enough to get me started on checking the voltages ( I reconnected the battery ONLY), which turned out to be ALL correct and again no signs of damaged components. I disconnected all the connectors and removed the board from the metal back plate to be able to have a closer look under the microscope. This was the EUREKA moment. While the normal inspection could find anything wrong, a closer look found tiny traces of corrosion in certain spots on the board-see pics below: 5940, 5954, 5955, 5959 Since the resistor R95 looked quite corroded, I started poking around (literally) the black compound covering the other half of it. 5945, 5946,5952 I have manufactured my own tool for the job: soldered a sewing needle to an old multimeter probe. As I was poking the black resin, I could see some oily liquid seeping from underneath. As I EXTREMELY gently poked and picked chunks of black resin, I had the deja-vu moment. This was the BREAKTHROUGH ! Just when we thought the bad caps nightmare that plagued the industry for more than a decade was over, the curse of the leaky caps strikes again. Now the culprits are the cheap CHENGX electrolytic caps used on this high end (?) speaker. The electronics companies never really learned the lesson ? It has become very obvious what I was dealing with: corrosion damage incurred by the electrolyte leaked from the caps and nicely concealed by the black compound surrounding various components. From this point on, you are about to embark on a long and tedious journey and I cannot emphasize enough about how gentle and careful you have to poke and pick the compound to expose all the affected areas , without damaging traces and the surface mount components hidden under the compound. Do not cut corners ! After all, cutting corners created this mess in the first place: clear nicely all the affected areas. The area around the AC input was not affected ( no caps) and didn't need to remove the compound. The next step was to neutralize the corrosive liquid and clean up the mess. I always had the best results with de-ionized (or distilled) water to clean the corrosion and the residue. Use a little semi-stiff artist brush for local clean-up, DO NOT submerge the board! Once you are happy with the outcome, finish the cleaning job with 98% IPA (isoprop alcohol). This one you should apply freely making sure it penetrates under the big components as well. You can do this twice if you feel like it. Th IPA will remove other residue and most importantly will remove the de-ionized water used before. Let the board dry nicely and at that point you can start assessing the damage incurred by the corrosion. 5960,5961,5962,5963 In my case, the resistors R95 and R97 suffered the most damage: 5952 R95 was completely corroded and came off, R97 looked a bit better but still had to be replaced. Luckily enough the pads were still ok, once I scraped off the oxide. Luckily I had exact replacements for the two 100 Ohms resistors and these are the results: 5964 So, were these two the root cause of my initial issue? Short answer: YES ! Long answer: both resistors were open circuit. Tracing the pads I found them leading to our audio ic U10, pins 8 and 9. Looking at the NTP8230 data sheet, pins 8 and 9 are SDA and SCL. Now it all make sense ! These 2 pins are the i2c communication lines with the rest of the board and they were disconnected (open). Our beloved audio chip is in i2c slave mode and although it was powered on, it couldn't talk to the master. So it would just sit there, doing nothing. Hence no audio output ! Reconnected all (except for AC power) and gave it a try. Wow, I soon understood why my coworker wanted this puppy repaired. The sweet sound coming out of this speaker was the prize of my hard labour :) Sooo, is the repair done ? Yes and no. Well, the leaking bad caps became worse and they will probably leak some more or dry out completely. In order to properly finalize the repair, all the electrolytic caps should be replaced with proper ones and reapply some compound (RTV maybe?) to prevent vibration damage ( it is a speaker enclosure, remember?). Luckily, digikey and mouser offer a very good choice of quality caps (Nichicon, Panasonic, ChemiCon) which will not break the bank either. Totally worth it (20-30 bucks total). All you have to do is to cross reference the original cap specs to make sure you get the correct replacement caps. CHENGX provides a spec table for their caps which is not the best technical sheet but it is better than nothing: http://www.bentex.com.hk/catalog/capacitors/electrolytic/index.shtml (copy and paste in your browser) Now, it would be REALLY nice if any expert out there would pitch in and provide a tested and proven direct replacement info for the caps replacement. It is time for me to move on to other projects, but I will still be lurking around for a while in case you have any questions regarding the above. Good luck everyone and happy fixing !

Yes this is a 'feature' of Bluetooth. (I have never seen the point of Bluetooth... Wi-Fi does everything it does, but better !) It DOES usefully enable a phone or tablet to play though headphones or speaker and to use a headset 'cordlessly'... Consider instead a 'Bluetooth Receiver' (under US $10 from China) connected to a FM Stereo Bug (Transmitter) - Then you can use any number of quality FM Radios (including phones with built in FM) up to 50 metres or so away... example: http://www.ebay.co.uk/itm/Wireless-3-5mm-Stereo-Audio-Adapter-A2DP-Bluetooth-Dongle-Transmitter-Receiver-/141227224470?pt=UK_Home_HomeDecor_Accessories&var=&hash=item20e1cc6d96

Most likely. Good luck with the outboard supplies. Or else, just buy some cool SM57s and be saved. Peace-

Use a mixer with Phantom Power. Otherwise, forget it. Or get an external supply. Peace-

Darn, I do this kind of work, but am in Caracas. So sorry.... Think of around 40$..? Peace-

Very delicate work. Take it to a Watchmaker ot a good tech. Do NOT clean with alcohol or any solvent ! I would say bring it over, I do these things, but I am in Caracas... Peace-

Check if U have Phantom Power on your mixer. If not, change either mike or mixer. Peace-

Darn, OK. First, check with a multimeter and find which pins give you around 200 Ohms. Next, touch one tip to the chassis and find the GROUN pin on the cable (lowest resistance) The GROUND goes to pin 1 on XLR The other two go to pins 2 and 3. Sorry I can't tell you which goes to which (phase), but you can check putting it next to another one and seeing if they sum or cancel. If cancel, invert them two... Peace-

You need Phantom power for condenser mikes. No mac gives that. Use a dynamic mike and try, now you know. Peace-

Open up carefully. Something came loose on the ground cables or the chassis inside. Tighten screws, check cables, and connectors. Peace-

I would see if the Phantom Power is OK. Check with a voltmeter between pins 2 & 3 on the feed cable. Should be around 40 Volts. If not, check it on another mixer. Now you know. Peace-

usually just a normal XLR (or Cannon) cable. BUT you must connect to a mixer with PHANTOM POWER. If not, nada. Peace-

These things use Phantom Power, from your mixer. If it HAS it. If not, now you know, get an external supply ($$!). Peace-

Dude mine died a week ago heard this constant buzzing sound wouldn't connect to anything then litterally lost all power it is now a beautiful paper weight. contacted the vendor told me if I didn't have a receipt I was S.O.L ... And everyone that owns one knows it's plagued with issues. For me it was serious connectivity issues right out of the box I had to buy a Logitech Bluetooth receiver to even connect to the thing which is 12' from the source... It would be nice if the vendor would help people that invested 400.00 in their speaker with the expectation that it would an investment

No it is not. This is going to be a wiring/grounding issue. Most likely coming from the source equipment.