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  1. Well, it's back to standard, apart from the 820k resistors on r5 and r6 and the master volume mod. Sounds just how I want it to sound now so that's the end of tinkering with it. Will just be basic maintenance like tubes now.
  2. Well I've been thinking about this the past few days and I'm going to put the amp back to stock. I will keep the master volume mod though. Reason being is that I used my laney vc30 for the first time in ages yesterday and it blew the epiphone away 😕 Might be the difference in output tubes? Obviously 2 5881's in the epiphone and the laney has 4 el84's. Could be speaker related too of course, 2 x 10' jensens cq10's in the laney The laney just sounded so much better and its annoying because I love using the epiphone 😭 Not sure what to do
  3. The r39 mod is definitely worth while and quite simple to do. It effects both channels so you can crank both while retaining a bedroom level volume. I've not noticed any tone difference with this mod so its win win. I run mine on triode too, I've not tried pentode with the new mods yet but got a band practice tonight so will give it a shakedown
  4. Another update as this thread has seems to have died 🤣 R21 is now 1.1k and C15 2.2uf, made a nice difference to the drive channel and the tone controls seem a lot more responsive. So list of mods I've done are: Master volume (R39) R15 now 1.5k R21 now 1.1k C15 now 2.2uf C3, C5 and C6 removed Standby switch deleted Fan power moved from valve supply area to before the 5 diode's (V1 - V5) That'll do I reckon, very happy how it sounds now.
  5. Super thread resurrection!!! This thread has helped me a lot with my BC30! Got hold of one about 6 months ago, first thing I did was swap out the sovtek output tubes which made a huge difference. All the 12ax7's are JJ's, so is rectifier. Also have cut out c3 c5 c6 and added master volume on r39. Have moved the fan power supply from the middle of the board to the place indicated on the schematic. Amp sounds killer and it's now my main gigging amp. Going to give the r15 mod a go, parallel a 5k resistor to the 2.2k to see what happens and then that'll probably be it!
  6. Well, turned out to be a failed drive pot, changed it, also deleted the standby switch, all is well again
  7. Hello all, Picked up a BC30 yesterday and I've come across a problem with channel 2. It sounds good (will do the cap mod though) but the volume keeps dropping out randomly. It will go real quiet and turn quite fizzy? Then it'll come back to normal and keep repeating. The preamp valves are the original Chinese cheap ones and the power valves look original too (sovtek date stamp is 02). Rectifier valve has been replaced by a JJGZ34S at some point. I've tapped all the valves and they dont seem to make any noise when powered up. Is it best to try new power valves to start off with? Looking at some tung sol 5881's. Never had problems with that brand. Channel 1 doesn't have this problem at all, swapped v1 and v2 but the problem didn't move. Have also noticed that the gain pot was loose so have tightened that up and reflowed the solder. But if you press on the knob you can hear a pop through the amp. I've ordered a new alpha a1m pot so hopefully that'll be fixed. Any possible help would be much appreciated! Thanks Matt
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