JapanAxe

Well I’m now rolling my own.

Well that's interesting. I have been studying the guts of the Bugera with the schematic to hand. I identified all the connections to the output transformer (OT) so that's good. There are three secondaries on the power transformer (PT), which you can see where they connect to the main PCB in the photo below: grey/grey - I measured 373V AC, bridge rectified (there's no centre tap), with a B+ of about 500V DC orange/purple/orange - 20.5V-0V-20.5V AC, rectified to give a split rail supply of +/-24V DC. This is further reduced to create a DC supply for the heater filaments in the three preamp valves and +/-15V to run the digital reverb board. 20.5V AC is also run through a couple of stages of voltage doubling (C73-C75, D20-D22) to create -76V DC, then dropped to -56V DC for the bias supply (all measured). yellow/yellow - 6V AC (measured - within 10% of 6.3V so it's fine) for the heaters of the phase inverter and the four output valves. The Bugera can run EL34s in place of 6L6GCs. EL34s need 1.5A heater current each but 6L6GCs only 0.9A so there is sufficient capacity to run all the valves in my build without messing about with DC supplies. Also I can tie off the purple centre tap and rectify the orange/orange 41V AC to give me a nice -57V DC for my bias supply. We have a plan!

The Bugera PCBs won't be involved in my build. I'll be making my own eyelet board - the layout will use some aspects of the original, but modified to accommodate the smoothing capacitors which Fender used to put in a separate 'dog house'.

I've decided to base my build on the Fender Bassman 100, with a circuit more or less like the one below. In the past I've reduced such circuits to one channel with a single input but I like the idea of being able to use this as a guitar head too. Rather than jumper the inputs (which would work, as the channels are in phase), I'm thinking of having a single socket that connects to Input 1 (high gain) of both channels. Then I'd have a 3-way switch to select channels (Bass-Mix-Guitar) and use the channel volumes to mix their relative levels.

Below - the donor amp, minus front panel. The seller was proudly demonstrating its clean, crunch and filth sounds when I admitted it was going to be reincarnated as a bass amp. I think that made him a tiny bit sad... All the 6L6GCs test good and are perfectly matched so need to drop a ton on buying a matched quad. Two of the 12AX7s are good, two test as 'worn'. Result.

I hope never to find out...

I’ve just snagged a 120W valve guitar amp head from eBay and all being well I’ll pick it up tomorrow morning. My plan is to use the iron and valves (and possibly some of the hardware) for my build, harvest any other usable parts, and move on the headshell. I have a slightly more compact headshell that I obtained in a trade. The new amp should deliver 100W+ from four 6L6GC valves but I haven’t yet decided what to base it on.

OK, decided not to mess with the pickup selections - the good sounds are already there (good job @Dood!). Did this instead, and fitted a 100nF tone cap which gives more range on the tone control.

I hit this problem when the first lockdown happened - suddenly I had loads more time (no commuting) but found I lacked the motivation to do the things I’d always wished I had time for. What helped me was starting a Bullet Journal, and I still do it now. I use it just for the fun stuff (bass, guitar, keyboard, singing, electronics) but many people use it for all aspects of life. I note down (in ‘spreads’ - see video) things I want to try, improve on, buy, sell, build, repair, whatever. At the end of each day I give myself 2 or 3 things to do the next day - I don’t always get them done, but every day I have a record of the small steps I’ve made to reach my goals. It’s a way to: - Track your past - Organise your present - Plan your future Here’s a good place to start:

I have for now abandonned the idea of adding more switching options to my D-Roc. Instead I tackled the issue that was more pressing to me - I can never remember how I last left the rotary selector switch! So I popped off the metal knobs and replaced them with push-on chicken-head knobs as pictured above. Now I can instantly see (and just as importantly, feel) where the selector is set. Result. *Apologies to Frank Zappa and Ike Willis.

May 2 gigs June 4 gigs July 1 gig (2 if you count playing at my niece’s wedding ceremony - yikes!) August 6 gigs (that’s more like it!) September 1 gig A bit variable, but I’m actively seeking out more band work on JMB.

I’ve seen some discussion that Rhythm Stick was originally recorded a semitone lower but the pitch was raised by speeding the tape up. It would be a lot easier if the open E string were available. Not sure whether anyone has asked Norman about it.

You and most cover bands then! When I play it on skinny-string guitar I find the trick is to count the drummer in. The first guitar note is on beat 4 but most people seem to hear it as the back of 4. One of the ways I work on improving my bass playing is to keep a folder of dots for numbers I struggle with. Now and then I have a bash at one of them. It currently contains: Highway Star Hysteria Master Blaster New Born Son of a Preacher Man

A friend of mine is a solo guitarist/singer with backing tracks and all his kit is linked up wirelessly. His only cables are for mains, and he covers these with hefty rubber mats. The benefits to him are (1) quicker setup, (2) less stuff for drunken feckwits, sorry punters, to trip over.