1985 Gibson Chet Atkins Classical ~ pickup preamp

Hard to believe it's been five months since the last post ~ where does the time go?

Here's a fantastic Chet in rare white (aged to blonde) finish.  The owner complained of a pickup issue wherein some of the strings were considerably quieter than others, making this guitar unplayable when plugged in.  This pickup configuration is quite rare and acquiring parts or repairing the transducer is nearly impossible, so the challenge was to repair the problem while keeping it all original.  The very expensive alternative would be to replace the saddle completely and install a new pickup system, which would be rather arbitrary and likely unnecessary.






This was a very innovative system for 1985.  There is a transducer for each string integral to the saddle and connected to a preamp via a ribbon

cable.  On the circuit board of the preamp itself is a trim-pot to adjust the volume of each string individually, allowing the player to customize the EQ of the instrument for more bass, mid, or trebbly output.  Quite cleaver.  Then there is a conventional master volume and tone control easily accessible on the upper bout of the body.

After a thorough cleaning of each internal and external pot as well as the area in and around the saddle itself, there was still a noticeable drop in volume from the low E, D, B and high E strings.  My fear was that there was a break somewhere along the ribbon cable itself, but it didn't make sense that only those strings would be affected.  While the solder connections at the circuit board that connect the ribbon cable appeared intact, a much closer inspection revealed that the fragile ribbon cable had somehow been folded downward along the bottom edge, severing the connection at the solder joint.  It then became obvious why ~ the battery had no clip and was housed rather loosely beside the circuit board, and had bumped against the connection to sever the link.  In turn, the plastic in the ribbon cable had become very brittle and delicate over the years so it was an accident waiting to happen.

So I put my Dentist hat on and armed myself with a tongue suppressor, some dental tools and a magnifying glass to isolate the wire from the ribbon cable and the pin connector at the problem strings.  Once complete, each link was re-soldered into a much more robust connection.  I also had to add a very small 5mm length of three strands of hair-thin wire to the high E connection to bridge the gap.  A very delicate process indeed.  Once complete and after confirming that the problem was resolved, I coated the connections with a generous amount of transparent super glue to strengthen the entire area.

It was then time to address the battery.  Unfortunately, I didn't have a suitable battery clip in stock to install.  Instead of making the trip to the store to purchase one, adding another hour to the job, I decided the more economical way was to make one.  I have various scraps of metal for just such a thing!  A piece 55mm (that's about 2 11/64" for you non-conformists!) in length would do.






Bending it in the vice leaving 17mm (21/32") for the thin side of the battery, then pinching together the opening slightly to add a spring effect made this a very strong clip.




Installed with industrial double-sidded tape (to negate drilling any holes for mounting screws) and this job was complete.  Very happy to have kept it all original.  This guitar is ready for another 29 years of classical wizardry!  I hope Chet would be proud...

1972 Traynor 2x15 cabinet

We recently acquired this cabinet for the arsenal and it arrived infused with a thick coating of nicotine and THC ~ and smell to go with it!  It's missing the Traynor badge, but the screws alone are a tell-tale sign of where it was made.  Only in Canada would a manufacturer use Robertson-head screws!









Equipped with a pair of Marsland 15" ceramic magnet speakers, which give it a super clean, fat tone with a throaty midrange.  The design was originally for bass, but many guitar players have found these speakers quite excellent for Fender-type amp tones with single coil guitars.



We disassembled the cabinet completely for cleaning.  A good scrub-down of warm soapy water did the trick and the brown sludge that resulted was used for weed control in the garden!  It cleaned up very nicely and now has a great road-worn look, plus it no longer smells like Keith's tour bus.  The grille-cloth on these 70's amps is much easier to clean than old tweed style cloth from earlier generations that used cotton as a main material.  Regardless, it still requires special care.

A spray bottle filled with 4 parts hot water, 1 part white vinegar and a few drops of scented mineral oil (to dull the smell of the vinegar) works very well.  Just make sure to remove the speakers first!  With the entire baffle removed, the grille-cloth was sprayed liberally then very gently scrubbed with a soft bristle brush.  We then used a shop-vac to remove all excess water and repeated the process twice more.  Huge difference!  Before and after pics below show the same area of the cloth.  Left in the sun to dry, it took on a classic vintage patina that didn't look stained at all.  This will sure look and sound great under our '69 silverface Bandmaster Reverb!










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Broken potentiometer shafts

Here's a Les Paul who's owner prefers the look of Tele Custom style volume & tone control knobs.  Not a bad option until a while later they go wobbly and off-centre because they're a set-screw, solid shaft type that don't fit properly over the typical splined shaft of a Les Paul or Strat.  Once removed, the two tone control shafts were broken as a result of the set screw and the volume controls were obviously destined for the same result.

In order to keep the original controls intact ~ and to have the guitar ready for a fast approaching gig ~ a workable solution had to be found.  The intact volume shafts were an easy fix/mod.  Inserting a 1/16" piece of metal cut to fit the gap in the splined shaft is an effective repair that is easily reversible.  You can see how the lop-sided knob has dug in to the maple cap, which won't be a factor after this.  For the tone controls pictured above, however, I had to think outside the box...

It needed a small piece of sculpted 3/16" diameter steel rod to complete the missing 2/3 of the shaft, effectively making it a solid shaft.  Where to find such a thing without driving across town to the industrial metal supply store to ask for scrap?  Peg Board hangers!  They are the exact diameter required and also have a protective coating that prevents corrosion.  The added bonus is the little blue rubber ends ~ they fit perfectly snug over the 9v adapter cable train to stop shorting out of the unused terminals of my pedalboard.  For a package that was less than $2CDN at the local hardware store, this is a great find!

After some persuasion with a hacksaw, vice grips,  sander, file and some super glue, the solid shaft was established.  Granted, this can't be used with the original knobs but for this particular instrument it's all about function and less about fuss!