Tuesday, 21 April 2009
Mucking about with valve amps is fun...but less so when the original manufacturer of my amp project's idea of a safe mains connection was a knotted (for strain relief) length of two core with a 1.5 amp slow-blow fuse in a weedy holder, they didn't have health and safety in 1964 clearly. As a concession to modern use I've chain drilled and punched out a hole in the back of the amp chassis for a three pin euro-socket, added a proper period Bakelite fuse holder and grounded the chassis to boot...that ought to stop all that leaky electricity making a big puddle on the floor that someone can step in!
I keep finding bits of redundant circuitry (left over from it's tape recording origins) in the amp as I work on it and have great satisfaction in ripping it out. Every time I junk something I fire up the amp to check I haven't trashed anything vital and so far so good.
Even though I've used valve guitar amps most of my playing life, their inner workings...short of simply swapping tubes...have always seemed some sort of voodoo to me. I decided that was going to change, so I started reading up on valves and amplifier theory...In fact I've gone a bit mad and burnt the midnight oil more than a few times learning my plate resistors from my cathode bias. This little amp has taught me more already than I can quite believe.
I'm now scouring e bay for a vintage 16 Ohm 12" speaker to go with the little beastie.
Monday, 20 April 2009
First little job on the valve amp was to remove the 'play/record' switch. This two position wafer switch gave me some headaches when I tried to figure out how to rewire and cut it out of the circuit......
It took an evening of looking it the job and a night of sleeping on it to work it out! I seem to have got it right as the little beastie fired up without self destruction....granted the wiring is a dogs breakfast and needs a length of tag strip to tidy it up but I have succeeded in impressing myself.
Now I need to sort out the input gain, as a humbucker overdrives the poor little machine too far!
Wednesday, 15 April 2009
I have just come by an interesting old amplifier........It languished in a busted tape recorder circa 1964 until it found a home with me. I would have loved to get the old reel to reel mono beast working again but the heads were stuffed, so out of curiosity and simply coz the valve layout looked a bit like a Fender Champ...I bunged my Strat into the mic in and was rewarded with a beautifully gutsy overdriven growl......hummmm.......Okay so the strain of putting a guitar through the strange oval 6" speaker caused bits to fall off of the plywood casing, but the sound was there, so I spent a happy couple of hours removing the amp from the casing and separating it electrically from the tape recorderish bits that would no longer be needed.
On the bench it fired up again fine......this time through an 8" guitar speaker I happened to have about the joint...Sweeeeeet but bloody dangerous with exposed mains wiring etc.
Next Step? Well perhaps a new custom casing to make baby 'Plexi' head, proper tone controls for bass mid and treble(hi fi amp tone controls suck the big one with guitar) . A master volume shouldn't tax my amp modding skills too much...and of course a standby switch to save those Mullard tubes!
Lets see, twenty quids worth of leathercloth and MDF....twenty quids worth of components equals a small hotrod 'boutique' style head for the studio or small gigs (10-15 watts)......a saving of several hundred knicker!
I’m off tomorrow night to see ACDC at the O2 Arena…….A happy accident as I was invited by one of my guitar students to go with him.
I have always had a great respect for ACDC, they have served up solid unpretentious, chauvinistic, testosterone fuelled hard rock since Adam’s dog was a foetus……and the quality of the product never wavers.
Angus Young, apart from in interview coming over like Sir Les Patterson’s bastard lovechild, is a stunningly expressive blues rock soloist; idolised by fans of the band but never really given the credit he deserves by the ‘serious’ music press……however the genius of the band in my opinion is his brother Malcolm. Always a bit in the shadows Malcolm Young is the ‘boogie engine’ of rhythm guitar playing……like Mick green of the Pirates, Wilko of Dr Feelgood or Pete Townsend, he builds a solid and instantly recognisable framework for the band’s swaggering ‘in your face’ style……plus he has the balls to play a Gretch!
Thursday, 9 April 2009
Above you can see the SG strung and next to my 'number one wife' Strat. Okay I still need to do a little more action adjustment when it has gotten used to being a guitar again....but initial playing brought forth the expletive '----king hell'...... the difference between it's sound before being smashed to smithereens and after rebuilding is dramatic with the sustain is surprisingly much improved. The sound is typically SG: sweet and round until you drive the amp hard when it becomes a tight, raw, aggressive bark. I have difficulty in believing that this is a £200 quid copy that has been well trashed in the recent past...I have heard real Gibbo SGs (usually seventies/eighties ones) that sound much worse than this.
I think stripping off the straitjacket of the Poly finish and giving it a Nitro one like a real vintage SG has helped the instrument breathe. This coupled with the added neck mass of 2.9mm frets, a real bone nut and a damn good setup as raised this old girl's game. The pickups remain the alnico magnet Wilkinson originals...and damn fiddlingly good they sound too!
Tuesday, 7 April 2009
years of gigging without even a refret! Solutions are there.....lets go innovate!
So unveiled here is my design for a relatively cheap instrument built with a chambered semi acoustic ply body a maple neck.
This may be my next project.......Oh yes the design is copyright 'Cocksoldier Guitars 2009'
Monday, 6 April 2009
The work on the SG copy is nearing completion, as is my usual quirky way of doing things I have 'flatted off' the last clear coat of lacquer before fitting the hardware and allowing the finish to harden for a month before polishing and relicing it (if relicing is not a word I'm officially making it one!) I won't be going for trashed finish as I have done on some Fender relics I have built....just the well played sweat and bar-room look.
The guitar formally known as the 'green mess' my scratch built roughly Les Paul Junior inspired baby is also now advancing after her decade of being in the bedroom cupboard. The experimental green polyester gloopy-crap finish was stripped....except for the the bits that got into the grain. The headstock has been sprayed black and a home brewed 'Junior 79' transfer applied. The 79 bit refers to the fact that this year it is the thirtieth anniversary of me building and selling my first custom guitar.....it was a bass anyway , but that by the by......
I have decided to put the Artec active onboard preamp/distortion in the Junior.......see this demo
I like the idea of a guitar I can take to a jam night......and when the house band guitarist tries to make himself sound streets better than everyone else by removing all the decent overdrive on his amp for any one else using it (that's a common trick around here)......I will have a little secret onboard weapon! For seventeen quid from Axesrus how can you go wrong?