Fender Hot Rod Deville Makes Funny Noises!

Matt from My Twilight Pilot told me that his wonderful Fender Hot Rod DeVille had developed some strange noises.  The volume control was really too sensitive, no low end audio, audio clipping, and we were experiencing some general shakes, rattles, and rolls.  Could the Unbrokenstring Crew help?

Finally, an appropriate warning label…

This brand new tube chart clearly shows that this is one of the wonderful reproduction units from Fender.

Service literature is easy to get from Fender for this model.

The treble tone cap was replaced with a silver mica unit (already installed.)

The bass tone cap on the right was replaced with the orange film cap on the left.  The larger size buys us some reliability as the internal dielectric is a little thicker, a good then when operating at a plate voltage of 350 volts.  The mid-range tone capacitor was also replaced with another orange CDE cap of the proper value.

The tone stack capacitors are now soldered in.  The leads will be trimmed and the rosin flux will be cleaned off.

When the signal generator was swept through the audio range, a mechanical rattle was heard in the vicinity of the reverb tank.  I’ll loosen the reverb tank and do the test again.  This thing IS loud!

A quick check of the electrical connections shows that everything is as it should be.  But the rattle remains!

The loudspeakers are a little loose, but no rattle here.

Aha!  It’s the bottom of the baffle board.  All the bolts were loose.  Here they are re-torqued to about 5 ft-lbs.

A fresh set of output tubes were run for four hours and re-biased per Fender specs.  A 12AY7 was installed in the first preamp.  This tube has lower gain than the 12AX7 used at the factory.  This change gives a little more ‘spread’ to the volume control, increasing its usefulness.

This is a view seldom seen unless you are in the business!  Nice lead dress.

To do the full-power tests, the window is opened and the amp is turned around.  Yes, this is VERY LOUD!  And quiet when it should be.  My job here is done.

Support this local band!

Thanks for reading all the way to the end!

Contact – David Latchaw EE
Cell – 281-636-8626

How Gibson Les Pauls Lose Their GForce Tuners

I own several old Gibson guitars , so I am only passively interested in, and mildly amused at, the flame war over the self-tuning GForce system included on new Les Paul guitars.

Jacob of The Unbrokenstring Crew said “The Internet is where nuance goes off to die.” Like most topics of discussion, the flame wars over the Gibson GForce system has devolved into a bipolar, binary love/hate relationship. Perhaps, someone actually thought about the situation, and decided that they would sell more guitars WITHOUT the GForce system installed. To that end, our local national guitar retailer has received some interesting tool in the mail.

These blocks of steel have nylon alignment pins that fit in the factory tuner holes used by the GForce system. The small holes are where the headstock will be drilled for manual tuners of various makes and models.  The Klouson holes are in the wrong place, so we are only installing Grover tuners for now.

Here is the back of a Les Paul headstock with the GForce system removed. Except for the indentations in the wood where the printed circuit board traces were, you would never know that they were there… more or less…

The GForce tuner assemblies were removed from the headstock. These are to be returned to the Global Headquarters of the National Guitar Retail Chain when we are through.

Perhaps they will salvage the rechargeable batteries, or maybe they will be used for spares as these fail in the future on other guitars. Hey, it could happen!

The nylon alignment pins hold the template in place. Drilling a hole and installing new manual tuners is straight-forward.

Grover tuners, anyone?

How about some locking Grover tuners?

For the purists, here are some Klusons on an older guitar.

I will not weigh in on the flame war over the deployment of the GForce system. But now you can go to a retail outlet and find a 2015 Les Paul that does not have the GForce system installed. We’ll see how this decision plays out over the coming years.

Thanks for reading all the way to the bottom!

Contact – David Latchaw EE
Cell – 281-636-8626

Gallien-Krueger 700RB MKII Hit By Lightning!

In a few instances, poor wiring in the venue has killed sound equipment.  More rare is the instance when you are actually playing and lightning strikes!  If you are Angus Young, being “Thunderstruck” is OK, otherwise, it is NOT COOL.  This Gallien-Krueger bass amp was soldiering away at church when a nearby lightning strike ended the Praise and Worship portion of our service.  Could the Unbrokenstring Crew help?

Let’s start off with some gratuitous tech porn.  This unit has a built-in DI box with a balanced output.

We have all sorts of tone-shaping capability.

The separate outputs for tweeters and woofer are nice.

The effects loop connectors in are front, as well as an easy means to attach a tuning pedal.  The POWER / PROTECT LED is RED until everything stabilizes, then turns green;  And, of course, the ubiquitous ON/OFF switch.

Here is a block diagram for those who are unfamiliar with all the architecture and features of this amp.

These speaker outputs connect the combined woofer and tweeter signals to a cabinet.  The AC input is self-explanatory.

These Neutrik connectors allow access to the separate tweeter and woofer amps, if that works with your cabs.

The fuse was blown, but I smelled something burnt.  The main circuit board needed to come out.

We had a blown fuse, so I did some troubleshooting before replacing the fuse and powering up again.  The filter capacitors were slightly swollen, so I checked them for ESR.

The ESR meter showed that these caps were OK.

The only visual sign of anything burned was this residue from an arc flash. Little bits of metal are burned and blown around the vicinity of an electrical arc.  The electrical surge of the lightning transient plus the conductivity of the ‘smoke’ from the arc flash blew the fuse.  All this happened during the lightning strike.  Fortunately the circuit board was not pitted.

The case was pitted.  This is where the metal in the arc flash came from!  We’ll clean this up and then replace the fuse.

Everything worked well.  The unit was returned with a very modest repair bill.  We have yet another happy customer!

Thanks for reading all the way to the bottom!

Contact – David Latchaw  EE

cell – 281-636-8626

Ibanez Bass Fretless Conversion

This straight-ahead Ibanez four-string bass will become a springboard for a bassist to expand his musical horizons. Can the Unbrokenstring Crew turn this into a fretless bass? Let’s find out!

Because this will be a training tool and not a piece of performance art, the customer wanted the fret channels and position dots to remain visible.  Maple, a contrasting wood will fill the fret slots.  The maple veneer is coiled up in the yellow box next to the bass.

We’ll take one last look at the frets.  Say goodbye!

These strings are the original OEM Malaysian strings.  These are headed for the recycle bin.  The customer also asked that the headstock logo be removed, to add a little mystique.  The tuners will be removed and stored.

The tape protects the fret board from me.  An Exacto knife clears away the junk from the bottom of the fret to be removed so we can have something to grab.

With a little care, the Exacto knife blade can be pushed under the fret wire to start the removal process.  Do Not Attempt This At Home, Kids!

Each fret is heated with the soldering iron.

These Harbor Freight end-nippers have been ground flush and serve as a pretty good set of fret pullers.

What the Exacto knife started, the fret puller finishes.

This takes a few moments so that I don’t tear out the wood around the fret tang.

Houston, we are clear the tower.  Rinse, repeat.

These are headed for the recycle bin, along with the strings.

Some Dr. Ducks Ax Wax has just enough petroleum distillates to cut the headstock silkscreen.

The head stock logo yields easily to a little Dr. Duck’s and a little Elbow Grease.

A tiny bit of compound restores the gloss in an even manner.  You can’t tell the silk screen was ever there.

Say goodbye to the identification decal, too.  What the customer wants, the customer gets!

This was a decal, so it shattered into tiny fragments.  Be sure to remember this trick when you steal your next guitar.

Now we move to the maple veneer.  The material we are using is sold as edging around laminate counter tops.  One face is covered with a thermally-sensitive glue.  This glue can be easily removed with some paint stripper.

The stripper was brushed on, then scraped off.  This is kinda fun!

After the paint remover evaporates, we cut the veneer into two and a half inch long strips.

The bottom of the fret board slots are curved at the same radius as the fret board.  So I am using this home-made radius gauge as a cutting guide to radius the bottom edge of the maple veneer to match the bottom of the slot.

An Exacto knife makes short work of the veneer.  You sharp eyed visitors may note that the Ibanez bass fret board is 14 inch radius, not 13.  Leaving the center a little high allows a place for more glue.  This radius works perfectly.

As one edge is cut, the veneer is slipped out from under the radius gauge, and another cut is made.

The fret slots need to be clean and straight.  Here, my scraper is just the right size to clear out the slot.

The ends of this scraper were ground square, creating a nice slot cleaner.

The radiused maple veneer pieces were glued into the slots using hide glue.

This looks like an oriental stringed instrument neck.

After the glue dried, I used the end nippers to do most of the coarse trimming.  A fret board protector acts as a shim to raise the cutting edges off the face of the fret board.

Next, I’m trying out the Exacto knife on the maple.  Nice curly shavings came off the maple filler.

Working from the center of the fret board out, the single edged razor blade was perfect for the final smooth cut.  Note that a bit of the glue fillet is being removed here, resulting in a nice flat surface on the fret board.

Here is a closeup of the job the razor blade did on the fret board.  This will sand nicely.  A final check of the truss rod assures that the fret board is held absolutely straight, no relief or bow of any sort.

This Stanley spirit level has one edge machined to a very precise flat surface.

This emery cloth is a very aggressive and durable abrasive medium.

A sheet of emery cloth was cut to fit the machined edge of the spirit level.  Now we’re ready to build our own sanding beam.

The emery cloth will take at least two coats of contact cement because the first coat soaks into the cloth.

In case you missed the first one, here is the second coat of contact adhesive

The strips of emery cloth form a continuous abrasive surface along the entire length of the spirit level.

This heavy aluminum fret board gauge is just right to mash out all the air underneath the emery cloth.

The spirit level makes a sanding beam that is the perfect length for this bass fret board.  See the dust at the right end?

Now that the fret board is straight, we will reestablish the radius of the fret board with this 14 inch radius sanding block.

Radiused and straightened, we’re ready to apply a hard finish to the fret board.  Everything that is not fret board is covered with tape.  If you hadn’t noticed, the nut was removed prior to sanding.

I didn’t want to put much finish on the end grain at either end of the fret board in order to minimize any swelling or expansion that would spoil the shape of the fret board.  When the wood is sealed, I’ll go back and finish the end grain.

The unlabelled can contains Diamond Varathane Floor Finish, a commercial polyurethane finish used in roller rinks and bowling alleys.  I discovered this stuff when finishing pine furniture.  The Diamond Varathane was the only thing that would stand up to my cat’s desire to chew on the corners of the furniture.  Absolutely bullet-proof.

The first ten (yes, that’s TEN) coats were applied with a brush.  We are filling a lot of wood pores, you know.

The radiused sanding block gets quite a workout, starting with 80 grit, then moving finer.  This is 220 grit.  The tiny dimples around the fret slots are filling in with each coat of Diamond Varathane.  Ten coats were applied and sanded to radius over a period of nineteen days.

For the final finish process, the next five coats of Diamond Varathane are applied with an airbrush.  Here, the Diamond Varathane is thinned slightly with distilled water.

Thanks to my Darling Bride, this stirring moment in history will be preserved forever.

A plastic soda straw makes a nice disposable pipette to transfer the finish to the airbrush reservoir.

We’re loaded.  Not much finish is needed for the final coats.

Everything is assembled.  This little air brush comes from Harbor Freight, and is surprisingly good quality for cheap ChiCom junk usually found there.  The air and the flow of material is easily controlled on the fly, while you spray.

We are experiencing technical difficulties.  One moment, please, while we display a Test Pattern.

The sprayed finish goes on much more smoothly than a brushed coat, which is why I switched to the airbrush for the last five coats.

Now this is beginning to look like a fine musical instrument!

The exposed edges of the maple fret veneer is sealed with some Diamond Varathane as well.

For the last two coats, I also sealed the end grain of the fret board.

One coat on the fret board does not require much finish.

The last five coats were wet sanded.  Three coats were radius sanded with 400 grit paper, the last two with 1000 grit.

A little rain water was spritzed on the work piece.

Keeping the sandpaper wet is a good way to keep material from building up and clogging the sandpaper.

Wet Sanding At It’s Finest!

Tiny bits of the Diamond Varathane are floated away in the wet sanding process.

Thus begins the final sanding session, 1000 grit wet.  Very little material is actually removed.  This is just surface prep.

Here is the fret board after the final sanding and dry-off.

This is fifteen coats of Diamond Varathane, rubbed with a cotton cloth to bring out the shine.

Here is a nicer view of the hand-rubbed finish, with reflections courtesy of Mr. Brewster Angle.

Off comes the tape.  A tiny bit of wet sanding and rubbing is used to smooth the edge of the finish so that it blends into the original finish on the back of the neck.

Time for tuners!

Some folks can artificially age guitars with ultraviolet light to remove these ‘tan lines’ but I don’t do that.

Warning – Guitar Porn.

Oops, I need to remove some fingerprints on this side.  The nut is glued back on and we’re ready to reattach the neck to the body.

The action is, of course, WAY too high now that the frets are gone.

These strings are about 0.056 inch off the fret board at fret one.

As a sanity check, this gauge shows the same measurement.  This is a nice closeup of the finish on the neck.  The Diamond Varathane is absolutely rock-hard after curing.

I put this 0.022 inch feeler gauge under the string slots, then proceeded to deepen the slots to just touch the gauge.

Here is the A string file at work.

The plastic nut flows a bit when worked.  An Exacto knife trims away the flash.

Time to take any sharp edges off the nut.  Playing a fretless bass is all about the “feel,” after all.  After a neck shim and a simple setup at the bridge, this bass is ready to mwah.


Thanks for reading all the way to the end of this long post!

CONTACT – David Latchaw  EE


Crate CR2R Combo Refurbish

The oak cabinet houses a simple solid state amplifier and a Celestion G12 loudspeaker.  The rustic look is intriguing; the wife agreed that this matched the decor and would therefore be allowed into the house.  This particular amp was languishing in a pawn shop until Dave called me to bring the truck and refurb this guy at the Unbrokenstring Shop!

The grille, metal handle, and metal corners had plenty of surface rust.  The wood hadn’t been conditioned in, like, forever.  And, it didn’t play.  When shaken, loose parts were heard rattling around.  So we have a starting point for electrical test…

A scan of the front panel shows typical controls found on 1970s era units.  The LO input has a 10dB pad in series with the input jack.  The BRIGHT switch is a throw-back to earlier times.

This unit has a three-band EQ and a reverb tank.  As we will see later, the electronics were built by St. Louis Music.  Crate had licensed Ampeg’s intellectual property and were rebranding it into their own units.

Here’s a quick peek at the rear panel.

A pair of TO3 transistors handles the push-pull duties.  Nice to see insulators over the cases of the transistors, which may be at 40 volts or more with respect to ground when operating.

A foot switch can be plugged in here to enable or disable the reverb.  Don’t know if the LINE IN and LINE OUT signals are really ‘line level’ e.g. 2v or not, but back in the 1970s, who cared?

A utilitarian Celestion loudspeaker handles the electricity to sound transducer duties. This particular loudspeaker is in good shape considering that it is probably original for that time period.

I took this pic to preserve the location of the reverb tank wiring and the cable to the loudspeaker.  They are all RCA males.

The output from the reverb tank was manually marked with a Magic Marker. Interestingly, the Magic Marker ink has dispersed into the plastic jacket of the cable but is still visible.

I unscrewed the chassis and removed it out the back of the amp.  Yeah, we’re a little dirty and dusty.

Now we have a little more room to remove stuff to clean up the cabinet.  Two screws hold the reverb tank in place vertically along the side of one wall.

The grille is held in with some of these screws.  Everything is coming off in order to clean this cabinet and oil it.

The grille frame is pine, painted black.

Here we find Vincent Price’s “funk of forty thousand years.” TIP: If you don’t get the association, Google Michael Jackson “Thriller” lyrics.

This portion of today’s program is brought to you by Pledge furniture polish.  It contains enough petroleum solvents to clean the wood and condition the exposed wood in the scratches.

The bottom of the cabinet hasn’t been this clean since 1978.

Now, to start on the electronics. I took this pic to document the orientation of the BRIGHT slide switch.

Rather than unsolder these wires, I’ll remove the front panel jacks to liberate this side of the circuit board.

I’m going to disconnect this internal wiring to free the circuit boards.  This pic is for documentation purposes.

All the knobs pull off, no set screws.  These knobs have an interesting tri-lobed scheme to hold to the knurled shafts.

Removing the nuts will free this side of the circuit board.  This socket is covered in felt to keep from scratching the paint.

Remember this switch? The BRIGHT switch needs to be detached from the front panel.

Aha! Here’s one of the loose parts rattling around inside the cabinet. Only the component leads secured this part to the circuit board. Over the years, the leads were repeatedly bent by vibration, work-hardened, and eventually broke. No audio passes through a broken lead!  There are two of these guys running loose inside the amp.

The preamp board is loose from the chassis.  These controls will be cleaned and lubricated before reassembly.

Some service has been performed in the past.  Why can’t these people remove the old rosin solder flux?

More solder rework is apparent here.

The white stuff is RTV adhesive, commonly used to secure components in place so they don’t vibrate loose.  We have a problem here.  Can you see it?

More tech porn.  The topology of this preamp is pretty standard, with op amps performing the heavy sonic lifting.

Everything here looks pretty good.  Let’s fix what we’ve found so far.

This cap came unsoldered.  It checks OK otherwise so this will be reinstalled right where it is.

Remember those green parts that were found rattling around inside the chassis?  My fingers are pointing where they go.

Radio Shack had these parts in stock.  They are installed here.  This board is the power amp assembly.

The first amplifier IC right at the input is bad. It goes here, to the left of center of this picture.

My reassembly helper has decided to perform a Quality Audit.

The controls were cleaned with Blue Shower, then lubricated with Rid-Ox, sprayed directly into the control. The control shafts were twisted from one extreme to the other several times until the Rid-Ox evaporated.

The grille is firmly reattached to the cabinet. Loose grilles are often the source of mysterious buzzes and rattles.

This yellow gripper is handy as a screw starter.  The power amp board is being installed here.

And our old friend, the BRIGHT switch, is reattached here.

The reverb tank is refastened to the side wall here. The Pledge furniture polish does a good job of removing crud from the tank sleeve.

More reverb tank action.  Exciting, huh…

Those cables are finally put back where they belong.

This guy doesn’t look too bad now. This is just a straight-ahead practice amp, but the cool factor is bumped up because it’s a Real Crate. And it plays well!

Thanks for reading all the way to the bottom!

Contact – David Latchaw EE
cell – 281-636-8626

DigiTech TSR-24 Repair

This stereo rack mount effects processor had a couple of problems. When turned on, the display would flash. And the rotary encoder is busted.  And we really need to get this fixed this week.  And many parts are obsolete.  Can it be fixed in time?  The Unbrokenstring Crew to the rescue!

These units are, in my opinion, highly-under-rated. When they work, they sport an innumerable list of effects. When they don’t work, they are still prized for spare parts.

This unit needed a new rotary encoder.  If there is one mechanical design problem, you are looking at it.  This big knob sticks out farther than anything else on the front panel, and therefore takes a beating if the unit is abused.  And, of course, this exact part is not available anymore.  Let’s open up the unit and go to work!

A firmware upgrade kit is still available from an eBay vendor, that adds delay time and new effect algorithms.  The new parts go here.  This unit will not be upgraded at this time, but if you are considering the upgrade, it’s not difficult at all.

More tech porn.  This is a custom processor flanked with other members of the DSP chipset.

We need to remove the circuit board entirely from the chassis in order to replace the failing voltage regulator.  These nuts and washers all come off.  Fortunately, they are finger-tight.

Interestingly, the screws holding the front panel in place are Allen head cap screws.  They look very cool.

More Allen head cap screws secure the external heat sink.  The voltage regulators are behind this heat sink.

Just documenting where all the cables go.

The configuration of the wiring harness determines if the particular unit is 115vac or 230vac.  No switches or jumpers!

This pin was loose in the circuit board.  We’ll repair this solder joint when we get the board out.

OK, I think I got it out.

The voltage regulators are inside this sandwich of aluminum channel.  The big heat sink seen in a previous picture bolts behind the aluminum angle bracket, seen at the top of this photo.

With the top piece of aluminum channel gone, the voltage regulators are easily accessible.  DigiTech used a grey silicone pad underneath the regulators instead of messy grease.

The new regulator is soldered in from this side.  Can you tell that the three joints to the right are ‘shinier’ than the others?

The aluminum sandwich goes back together.

Now that the mechanical sandwich is secure, I am reflowing the solder joints to remove all mechanical stresses.

The loose pin seen earlier was not the only issue.  Two pins fell out of their holes!

The solder joints beneath pins at Q11 and Q12 were re-flowed with rosin solder.  The flux seen here will clean up with isopropyl alcohol.

This sub-assembly, called the “Pot Board,” carries the rotary encoder, the control with the white shaft seen in this pic.

That’s the problem!  Of course, this part is no longer available.

Here is a better look at the damage.  When the knob is banged inward, the phenolic circuit board used to implement the rotary encoder takes most of the stress.

Let’s clean up this mess.  No sense in leaving the broken pieces in the unit!

I prefer braid and rosin to clear out plated thru holes in circuit boards.

The plan will be to transplant the white nylon shaft and bushing into the new encoder body.

The new rotary encoder was dis-assembled.  The old shaft assembly is on the left, and will mate directly with the circuit board.  Note that this rotary encoder has a different land pattern than the original.  This circuit board will make fewer pulses per revolution.  In my opinion, slowing down the action of the knob is a Good Thing on this unit.

Here’s the completed “V’Ger” rotary switch.  The tabs on the back hold everything together, assimilating the two encoders; a tip of the hat to the Star Trek movie when the Voyager space probe ‘merged’ with an alien probe, then returned to Earth to ask the question, “Who’s my daddy?”

Here is a good view showing how everything lines up.

The new encoder board has a slightly wider pin spacing, but nothing that will keep us from finishing this project.

Here is the pot board assembly with the new encoder assembly installed.

That pot board assembly shoe-horns behind the front panel.  All the electrical connections are made thru the ribbon cable.  The cable needs to be mated first before the pot board is installed, because it won’t mate after the board is installed.  Don’t ask me how I know that…

Now everything fits.  This is a good view of the little bit of gun-smithing necessary to get the new encoder board onto the site on the pot board where the old one was located.  We’re on the home stretch!

Re-using the original shaft and bushing allows us to stay with the original knob and hardware.

The instructions to perform a factory reset are freely available online and in the manual.

All done!  No flashing display, and the rotary encoder knob steps through all 255 different banks of effects at a sane rate.  This unit is ready for another decade of duties around the studio.

Thanks for reading all the way to the end!

CONTACT – David Latchaw   EE

cell – 281-636-8626

Plato de Golpeado On Highly-Figured Wood

While lost in conversation with a friend, I picked up this guitar and started playing a few scales. The guitar was FANTASTIC!  Had I not been distracted, I never would have picked up such a presumptuous, pimped-out guitar. But this guitar will replace my stolen Rogue RD-80 acoustic.

I’m not too proud to show off the price tag. Minnie Pearl would be proud!

This thing is so flashy, traffic will pull off the road to let it drive by!

Eye candy all around!

Even the head stock is done in figured wood and mother of pearl.

While we’re gawking, check out these tuners; Really nice for an inexpensive guitar.

But, the darned thing was made in China. Gotta take the good with the bad.

Note that the nut is stepped, not uncommon on Ibanez guitars.

The intonated saddle is apparently made of the same stuff as the nut.  Ibanez calls this “Ivorex II”

My bride purchased this guitar. I took it home and did a setup. The fret board was as dry as the Sahara.

Likewise, the bridge hadn’t seen much care in a few years.

The previous owner was a smoker. Everything was covered with nicotine.

Something else that hadn’t seen much care in the last few years was the battery compartment.

The battery box needed a big clean-up.

Let’s string it up!

Among flamenco enthusiasts, the plato de golpeado, or tap plate, protects the sound board of the guitar from the finger taps, or golpes, a rhythmic percussive element of flamenco music.

This guitar has no pick guard, and I don’t want to put a pick guard that would hide the view.  However, a clear tap plate may be just the ticket to protect the sound board.

This product is a simple way to add a pick guard and not spoil the view.

A pair of scissors works this material easily.

Here is the other side cut to shape.  I rounded the corners to avoid sharp corners that would snag something.

One end is stuck down, and the rest of the backing is removed.

Another view of the peel and stick process.

In this view, you can see tiny air bubbles under the pick guard.  We can burnish these away.

A lint-free rag and some elbow grease is necessary at this step.

That’s better!

Jen puts this wonderful guitar through its paces.  No pick scratches on this guitar’s sound board!

Here is another review:

And a little bit more about how this model sounds (mine sounds like this but I can’t play it as well…)

Thanks for reading to the end!

CONTACT : David Latchaw EE

Guest Blogger – How Not To Buy Your Child A Guitar

WooHooo!  This posting is the fiftieth blog post for The Unbrokenstring Crew!!

I asked my high school sweetheart and wife of thirty-eight years, Glenda Latchaw, to tell her story concerning a disturbing event that she witnessed while shopping for guitars.  This story is offered in juxtaposition to my blog entry http://unbrokenstring.com/engineers-tips-selecting-first-guitar/ and is intended as food for thought for parents who wish to encourage their children to pursue music.


How Not to Buy Your Child a Guitar

Or maybe I should call this How to Embarrass Your Child in Public. Or maybe more importantly, How to Teach Your Child to Hate Playing Guitar.


I had gone with my darling husband to Guitar Center (shameless plug, you’re welcome…) to look at Ibanez guitars (I had just bought David a used one that he had played and fallen in love with to replace a stolen guitar and I was curious…) while he delivered repaired amps and picked up broken ones for his side gig, Unbrokenstring.com (You’re welcome, dear…). I had talked myself into getting a nice little Ibanez classical that I could bar all the way up and down the neck with my bad finger and I had just failed to catch my favorite salesperson, Laura before this family came into the area and grabbed her.


It looked to be a nice enough family, mom, dad, and two young boys. The oldest was somewhere in the middle of the grade school years and the youngest was maybe kindergarten or thereabouts. I heard Mom mention to Laura that they were there to buy the older boy his first guitar for his birthday since that was what he’d requested. I thought, “How nice. Kid’s got an interest in music and they’re going to encourage it instead of letting him sit in front of the tube.” That was pretty much the last thing I heard Mom say. I figured it’d be fairly quick. I mean, Laura has the boy try out some guitars, he picks one out, and they buy it. Right?




Dad opened his mouth next. I could immediately tell he didn’t want to be there. I’m not sure if he was unhappy that the boy wanted a guitar and not some more … intellectual instrument (my intuition’s favorite choice), or that this was going to cost him some money, or that the boy had made a decision without asking his father’s opinion.. Dad seemed a bit of a control freak. And he obviously wanted out of there as soon as possible. He as much as said so as he was staring at his watch. (What a way to make a child feel special. Way to go, Daddy Jerk!)


The boy was not permitted to look at anything on his own. Daddy Jerk did the looking. He wandered to the classical/flamenco wall. “Those have nylon strings. I don’t want one of those. The strings don’t last. I need steel strings so they’ll last.” Evidently the fact that nylon strings are gentler on delicate young fingers never crossed his mind. (Hello? If it hurts, he ain’t gonna’ practice, dodo…) He wandered on to the other walls.


“Those with the thin bodies, they don’t last as long, do they? I don’t see how they could. And they’re not as loud. They can’t be. The body’s too thin. I want a loud one.” He grabbed an adult-sized guitar off the wall. “Here, try this one. Really hit it. Be sure it’s loud enough.” The boy strummed it like you strum a guitar. “No, not like that! Harder! Like this!” He put his hand up next to his shoulder and swung it down like he was using a machete to cut off his toes. “It needs to be a loud one!” (Hate your neighbors, do you?)


He kept looking at the adult-sized guitars, pulling one, then another down and handing it to his son. “Try this one.” Laura tried suggesting he look at the ¾-sized guitars for the boy. Daddy Jerk told Laura, “No, I don’t want a small one. I want to get something big so he can play it for a long time, but not too expensive in case he doesn’t stick with it.” Yes, the child was right there, hearing that his father half-way expected him to fail. Mom said nothing. Laura looked a bit shell-shocked by this time. I was biting my tongue and wondering if my self-control would hold. My husband would have been proud. (He knows me. I don’t deal well with idiots and tact is not my strong suit…)


He asked Laura questions. Stupid ones, mainly. Laura was still too dumfounded with his behavior to say much, but that was okay. He wasn’t listening to her. He didn’t care what she had to say because she didn’t agree with him. He continued looking at adult-sized guitars. He never once asked the child what he wanted or what he thought of a particular guitar. He never noticed that the adult guitars actually forced the child to extend his right arm straight out from the shoulder to put a guitar under it. He never asked the child to try and reach across the neck with his left hand to see if he could actually ‘play’ the guitar. What mattered to him was that the right hand could make a lot of loud noise. (You jerk, just set the kid up to fail, why don’t you?)


The boy kept sneaking looks at the smaller classical guitars and the ¾-sized ones. For a smaller person (ahem, like me and that poor child) the adult-sized guitars are just too hard to handle. The necks are too wide, the bodies way too big. The boy knew it. He managed to take advantage of Dad’s distraction by the ‘big, loud’ guitars once to get his hands on a smallish classical. He put his left hand on the neck and was playing around with it. He could reach all the way across and fret that sixth string. He was comfortable with it and it looked good on his knee. It tucked neatly under his right arm. Daddy Jerk saw him. “Put that back. It’s too small. And I said I wanted steel strings on it.”(Hey, whose birthday gift is this anyway, <insert obscenity of your own choice here>?)


Another customer eventually took pity on the boy and handed Daddy Jerk one of the advertised ‘under $100’ guitars that he’d been playing, saying he’d been thinking about buying it himself. It was a name brand, Yamaha, I think. It appeared to be satisfactory in the loud requirement. It was still too big, but not quite as too big as the others Daddy Jerk had pulled down. Daddy Jerk looked interested. He was ready to get the flip out of there and here was this guy recommending this guitar. Perfect.


He looked at Laura. “What about tuning it? I’m going to have to tune this for him.” (What? Wait a minute! Isn’t part of tuning it part of learning to play it?? Did I miss something here?) Laura mentioned that the particular guitar they were looking at had the built-in tuner and demonstrated how it worked. “That’s good. We’ll take this one.”


And then on the way out of the acoustic room, Daddy Jerk asks, “Do you have any books of chords and things that he can use?” I interpreted that as “I don’t want to have anything else to do with this idiot instrument that my idiot child wanted,” even though all I heard was “I, I, I,” throughout the whole hour of excruciating hell that he had just put his son through in picking out ‘his’ birthday guitar.


In summary, this is how not to buy your child a guitar:


  • Act like you have something more important to do. This will make him feel really special.


  • Don’t let him look for himself. After all, you know best and it’s your money.


  • Don’t buy a guitar that fits his size. He’ll grow into it, assuming he stays with it long enough.


  • Don’t buy a guitar that he can actually play using both hands. It just needs to be loud. He won’t need all those extra notes on the neck for a long time.


  • Don’t consider something that might be easy on the left hand’s fingertips. Pain’ll make him want to practice all the time.


  • And most importantly, don’t ask what him what he thinks. You’re buying him the stupid guitar he wanted.


I hope the boy’s still wanting to play his birthday guitar, but I doubt it. Thanks, Daddy Jerk. I hope your younger boy asks for a real drum set and bangs on it all the time.



Glenda has published articles for The Texas Clogger Magazine, and was the creative genius behind the selection of ‘unbrokenstring’ as the Web identity for the blog you see here.  She is the dance instructor for The Rhythm Cloggers of Houston, Texas, is a charter member of The Science Fiction Book Club, and serves as staff for sixteen cats on the Sprawling Branch Latchawvian Cult Compound, hidden somewhere in northern Brazoria County, Texas.

Seymour Duncan Twin Tube Classic Pedal Refurb

This pedal was making a strange, whooshy noise. Could the Unbrokenstring Crew fix it? Let’s find out!

There are many pictures on the Web of the top of the pedal, but nothing about the back. Here it is! We haven’t missed much.

The bottom of the unit slides off. Four screws hold the bottom plate on the unit. I love that big non-skid pad on the bottom of this pedal!

An interior view shows the pair of 6021 tubes and the circuitry to support them. Most everything else is switching, tone and volume controls.

I located a stash of NOS RCA 6021 tubes from a resale shop on eBay. I purchased all they had.

Here are two volunteers from the group.  The individual wires are soldered to eyelets, rather than having pins that fit in a socket.

One screw removes a bracket that holds the tubes in place.

I cut one of the old tubes out, then unsoldered the pc board terminals.

This is a roll of Teflon tubing.  Some of this will be slipped over each lead of the tubes to keep them from touching each other.  This stuff dates back to my NASA days.

Pieces of Teflon tubing are cut to length and slipped over each tube lead.  The leads are then threaded through the holes in the eyelets, where they will be soldered.

Just a couple more leads to thread into the eye of the needle!

Each lead is pulled through the eyelet until the tube is seated in its final resting place.  Each wire will be hand-soldered and the excess lead trimmed.  As you might suspect, the second tube is replaced in a similar manner.

Having all the knobs pointing the same direction is a nice touch.

Sean and his beautiful bride pose for a pic!

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CONTACT : David Latchaw EE

Ex-GF Smashes Jackson Guitar

Can’t live with them, can’t live without them. A late-night call was the starting point of the end of a relationship between a young man and his guitar. His prized Jackson was smashed by a cray-cray now-ex-girlfriend, and his new squeeze sported dull, boring factory pickups. Could the Unbrokenstring Crew salvage anything from what had been broken, and spice-up the rebound relationship?

Here is most of what was left of the Jackson.  These pickups sounded pretty cool with his rig, so he wanted a pup transplant.  Beyond the bridge, strap buttons, switches, and maybe the neck, this guitar was now firewood.

I’m not into Jackson guitars, but that is some unusual artwork.  Maybe a fake?

Now this is a purty guitar!  Hope his new girlfriend isn’t the jealous type.

The neck pickup of the Jackson is a DiMarzio Evolution.  It measures about 13k ohms.

Yep, it’s an Evolution.  Steve Vai, anyone?

I’ll give you three guesses who made this Custom Custom pickup.  However, it is a tight fit for that trim ring because the trim ring is pulling the tape off the windings.  I can fix that.

The coils read 14.4k ohms, which tells me these are OK despite the rubbing damage.  Lidia Daniels wound this pickup!

This selector switch is OK but not needed today.  I’ll clean it up and return it to the customer.  What a hack job!

One of the broken pieces has this cut-out switch.  I’m not going to route the new guitar to add this button today.

We’ll clean this up too and return it to the customer.  The blue button would look ‘cheap’ on the deep red guitar.

The cadaver is ready for the body bag.  The police can clean up the crime scene.  Our job here is done.

The bridge pickup trim ring was scraping against the insulation on the windings.  A Dremel tool with a sanding drum created some space in order to set the pickup height properly.

However, the pickup height could not be set because a screw and a spring was missing.  I just happen to have here, in my formerly-nicotine-stained fingers, some left-over hardware from another pickup installation.

From this angle, you can see the bump in the pickup windings, and the clearance for the bump carved into the ring.

Yeah, that’s better.  Not too shabby-looking, either, after a quick buff and polish.

The factory pickups in this LTD F50 work fine, and will be removed and returned to the customer.  I have marked them N for neck and B for bridge.

We’re going in!  Everything here seems to be in order.  The pickup wiring goes straight to the selector switch.  Easy!

This is the DiMarzio in its new home.

All the wiring is pulled through the routes in the body.  The guitar is starting to look snazzy!

This does not look a whole lot different than it did before I started.

Pimp My Ride!  Y’all have seen new strings and a setup before, so we’re done with this blog.  One relationship ended, and another one begun.  BTW this guitar sounded FANTASTIC in the hands of the owner!


Thanks for reading all the way to the bottom!

Contact:  David Latchaw  EE