tatthecant Posted December 26, 2020 Share Posted December 26, 2020 Hello I have a Little Mark Tube 800, the volume is really low have checked all the obvious leads etc, taken it to my repair guy who is usually quite good, but he says he can't find what's wrong with it, has anyone had similar issues?, was it something simple ,an easy fix? or is the amp F****d, Cheers Quote Link to comment Share on other sites More sharing options...
MoonBassAlpha Posted December 27, 2020 Share Posted December 27, 2020 Have you tried bypassing the preamp section, plugging straight into the effects return? I'm thinking the valvein the preamp is a likely candidate. Did your tech try swapping it out? Quote Link to comment Share on other sites More sharing options...
tatthecant Posted December 27, 2020 Author Share Posted December 27, 2020 Not sure what he did , but I've used him for a few years now and he is pretty good, I think he probs did try valve as it's quite an obvious thing, but I'll try going through effects return later and let you know if it works, thanks Quote Link to comment Share on other sites More sharing options...
BassBunny Posted December 27, 2020 Share Posted December 27, 2020 (edited) I had exactly the same problem with an SA450. I ended up selling it cheap as a " half output" job. The alternative is to send it to Real Electronics in Sheffield who are the Mark Bass official repairers. The problem is that it would cost more to repair than it is worth. MB won't release the circuit diagrams and Real just swap circuit boards. Edited December 27, 2020 by BassBunny Quote Link to comment Share on other sites More sharing options...
BassBunny Posted December 27, 2020 Share Posted December 27, 2020 Just remembered an email I got from @johnny2shoes who managed to get his LM3 fixed by someone in Bolton. Might be worth messaging him. I'm pretty sure his was a Class A/B one, same as the SA450, rather than a ClassD, which most tech's won't touch. Quote Link to comment Share on other sites More sharing options...
ikay Posted December 27, 2020 Share Posted December 27, 2020 I found an LM Tube 800 circuit diagram here if that's of any use - https://el34world.com/charts/Schematics/files/_miscellaneous/Little_mark_tube800_sm.pdf 1 Quote Link to comment Share on other sites More sharing options...
Jakester Posted December 28, 2020 Share Posted December 28, 2020 I’ve just had my Combo Amp II (the combo equivalent of the LMIII) back from Real Electronics for similar issues. They tested it fully and couldn’t find anything wrong - the only thing they could suggest was a dodgy pot so they replaced all of the control pots - might be worth getting that done? Quote Link to comment Share on other sites More sharing options...
tatthecant Posted December 28, 2020 Author Share Posted December 28, 2020 Hello , I've tried bypassing preamp into effects return, no different ? Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.