NOISE-FREE TELECASTER

The Whys and Wherefores of Making the Tele Digital Ready

'Noiseless' pickups aren't the end of the story. New component swaps, rewiring, and fastidious shielding lowers the noise floor. Herein, an overview - with some thoughts on 'the electric', itself.


INTRODUCTION

As I was initially writing about my new Telecaster acquisition, I opened up the panels to have a quick look-see at the cavities and internal wiring. It was, in that brief instance, something of a surprise to see some rather ill-formed solder joints and questionable connections – especially coming from The Fender Custom Shop.

But it would be with a more detailed examination, following my written piece, I would know for certain that the previous owner of this otherwise magnificent 1996 offering had been inside, changing things around – then changing them back … kind of. Indeed, once I pulled the knobs, I further saw that the pots had been changed – using splined shafts of slightly different heights. This would have never come out of any Fender factory that way – no less from the Custom Shop.

But yes, many people – with even the most rudimentary of soldering skills – take on the rather small project of changing out the potentiometers once they become ‘scratchy’, or sometimes, they simply want to see what another resistance value might conjure in the guitar’s sound.

Still, there were additional signs that the guitar had been played with – more than the more common indications that the instrument had been played on, for it was essentially immaculate. Internally, the blade switch had solder loaded on terminals that would normally remain dormant, and a couple of those eyelets had, indeed, been ‘clipped’ – not at the wire, mind you, but the actual terminals, eliminating their apertures. I also noticed a couple of minor variants in the wiring that functioned normally, but still didn’t represent what was common to Fender. And then there was the general execution of the solder joints that remained in evidence. Not cold, per se. But not good.

And yet … the guitar played on, pretty much as intended – if with some transient noise between a couple of switch positions … something to be expected for a guitar dating back to 1996.

None of this conjured regret for having purchased this outstanding Custom Shop Fender, naturally. Yes, while many purchasers would like – or expect – the instrument to be perfection, right out of the box, I would be undaunted as the plan was always to swap out the parts under the control panel, in any event. It would be time, after all, even without someone other than Fender messing with it. And, moreover, I knew that I wanted to further lower the noise floor of an already quiet guitar …

IT’S ALL NOISE, ANYWAY …

Indeed, for those parents of the World War II generation, all “electrified instruments” (their term) represented the breeding ground for “noise” by virtue of their sonic existence. And the music associated with the ‘new fanged’ was also noise, to boot. But for many of subsequent generations, ‘noise’ was, indeed, the point. Loud, raucous, grating. Impolite. Such was the appeal. It was one long, windmill-strum sustain of “fuck you” to all that came before. The Dorsey Brothers could simply go fuck themselves with the slide trombone they rode in on …

Such was the birth of Rock ‘n Roll – even if its Surf Music cousin sounded much like it was spawned out of a church social, remaining polite, conjuring the sandy-toed, heartthrob response of holding hands, rather than the more pudendal throb of cumming inside. And somewhere in that metamorphosis of escalating intimacy, virginal to carnal … was Rock ‘n Roll.

Fast-wind tape to the future when tape, itself, would be abandoned …

THE NEW NOISE IS LOW-NOISE

So many of us sit here, on this day, with digital recording facilities that boast – and generally deliver – a huge signal-to-noise ratio and, by extension, a broad dynamic range - sometimes approaching or topping the 100db mark, nowadays. And many of our ‘circuit board instruments’ – from synthesizers to samplers – also deliver with similar, low-noise aplomb. Even more contemporary condenser microphones have, in this regard, out-paced the classic and revered Neumanns.

But … there is the ‘High Noise Potential’ of Low-Noise: Multiple, multiple, multiple-upon-multiple tracks …

My particular recording setup can serve up 255 raw audio tracks, 255 software instrument tracks, and 99 external MIDI tracks. Shit-loads of tracks, in short. The problem: Each and every track is its own little ‘noise generator’, no matter how low in noise each individual track may spec on paper (and a single track is, indeed, what they use to ‘spec’). So, go ‘Full Hog’ with your Digital Audio Work Station – without intelligence, and your actual noise floor will pull you back to that of an analog cassette machine of 1973 – without Dolby (kind of, sort of). Personally, if you’re running 250 tracks at a swipe, you may really need to ‘re-think’ the music, anyway (with precious few exceptions). The ‘extra’ tracks are generally there to print several versions of a take – perhaps to be ‘comped’ later on to some ‘clean tracks’. But even holding at, say, 24 tracks … noise can build up. Yes, even in digital.

But the point is this: With all of our track availability, we’re afforded the opportunity to ‘build our noise’, track by track – not only within the Digital Workstation, itself, mind you – but with each and every instrument (outboard noise generator) plugged into the individual tracks – be they synthesizers, samplers, microphones … or guitars. In short, digital is not your low-noise elixir, by simple default. Your problems are potentially compounded by the available access of your “Six Inch Tape” on virtual reels.

 

The control panel being inserted after the rewiring. Copper tape extends underneath pick guard to meet yet more copper adhered to that underside. The tight and narrow cavity also uses a clear layer of Scotch brand packing tape, cut to size (over the copper) to keep any 'hot' components or wiring coming into contact with the shield (ground). A bit more on this, somewhere below ...

QUIETING THE NOISIEST BEAST OF ALL

It is for the reasons I cited, above, that I can go though great pains (or attention to details) regarding all sorts of circuits (and even the power supplies that drive them). And I’ll do so in the interest of even a 1 ~ 2 decibel improvement in the noise floor – for, as I explained, noise compounds, and the floor raises – always heading towards the penthouse. And a single, 1 ~ 2db improvement … tracked four times over, say … yields that improvement, compounded, across the mix. And this doesn’t even consider the ‘digital doubling’ you may employ to thicken up the sound, out of the box, or in the mix.

But surely, the ‘noisiest’ of all instruments known to man is the ever-popular, electric guitar – be it conventional or ‘bass’. In fact, in pure engineering terms, the electric guitar is the biggest piece of audio-generating shit one has ever laid their hands on. Requiring mounds of boost to get a useable signal across multiple pickups – none of them isolated or ‘buffered’ from one another before combining or ‘blending’, with untamed inductances that vary wildly across variable resistors (‘pots’), further influenced by the ‘load’ they’re hooked into – amplifier or console – and additionally impacted by the very cabling used for the transfer of their micro-mini signal ... electric guitars, indeed, suck.

Of course, the work-around for the above – in theory – would have been active electronics, contained within. But at the time of the electric guitar’s inception, that would have meant the rather impossible task of cramming a series of vacuum tubes into the body, driven by a heavy transformer (and yet another cord). And, with this, your Ash-bodied Stratocaster would soon become … ash. And if the electric guitar had, instead, been created in the Integrated Circuit (IC) days of the 1980s, say, the instrument might sound similar – yet decidedly different ... And one’s ‘pet sounds’ may have been in notable absence. Likely, even.

For it is the very manifestation of piss-poor engineering, as an ‘Epic-Fail’ of high school Electronics class – even for a ‘passive circuit’, that guitarists use to ‘get their sound’ – with many not even realizing they’re truly playing with – or tweaking – a grand fuck-up of epic proportions, at its core. And that carefully, pot-adjusted fuck-up is … ‘their sound’. Indeed, a sizeable portion of the aural cues one uses to identify the instrument as being “an electric guitar” in the first place is founded in engineering defect and anomaly – one that wouldn’t be accepted in the crudest of home-built, passive mixers. And yet … it is the sound one clamors for – independent of its laughability as an engineering project.

Beyond this, for those of us who play electric (about 20% of the time for me, maybe), we find ourselves comparing notes regarding the deliberately imposed application of ‘distortion’. That is, how can we make this thing sound like shit – though less than complete shit – in a selective and tasteful kind of way? An upscale, snooty kind of shit, say. So clearly – given this, for the electric guitarist, the fact that one is playing a ‘Fire Safety – Don’t Do This With An Outlet’ wiring scheme behind the scratch plate is of little concern.

But what can concern them … is noise. Though, their primary noise-related nemesis is often ‘hum’ – at 50 or 60 Hertz, depending upon where they live. And buzzes. Crackles. Pops. Snaps. Clicks.

The ‘Hum Portion of The Program’ (not to be confused with buzzes, by the way) is often the nature of the beast, tied to ground. In fact, one old Nashville studio player – whose name I can’t recall to credit – made a “device” years ago that was comprised of a bare wire with an alligator clip soldered to one end, and a pinky ring formed at the other. When in the studio, he’d slip the ‘ring’ end on his finger, and clipped the other end to the bridge plate of his Telecaster, making himself the ‘path to ground’. Hum was decidedly diminished … and the buzzes would often disappear, as well. Rather effective, yes – but those Pete Townsend ‘windmill strums’ just had to hurt.

But naturally, the relative need to ‘cold water pipe’ one’s guitar is often reflective of the wiring particulars of the room, itself ... and what other devices surround you in that space – inclusive of what’s sharing the circuit, relative to the amp. For the very notion of ‘isolation’ is alien to the electric guitar. Its very design says, “Go ahead. Fuck me.” And it, in turn … fucks you.

Then there are the cereal-conjuring, snap, crackle and pops – almost invariably tied to the dirty, old men of guitars: The pots and switches. And yeah – bad solder joints, as well. While these ‘welds’ generally don’t come from the factory (though don’t absolutely count on it), I’m amazed to see otherwise competent ‘setup’ luthiers who can’t lay down a clean solder joint to save their lives – one that isn’t a pitted, grey blob of tin snot. And while they may work for a time, doom looms ahead.

Beyond this, there is what I call the ‘light surface noise’ of an electric guitar circuit. This, again, can come from bad solder joints and sloppy wiring practices that are also receptors to extraneous interference. And I’m not speaking of the obvious, ‘lamp dimmer’ buzzes. I’m talking about a light ‘micro-grit’ noise that rides shotgun, along side the desired signal. This residual noise would often be lost in the noise floor of analog - but no more, in the digital age. And just one bad solder joint or leaky capacitor can be a prime contributor.

REWIRING THE CUSTOM SHOP TELE

So, there I would be, closely examining my new Telecaster, three-pickup acquisition. A jumble of wires – true to Fender form – and a 5-way switch (to accommodate that extra pickup). The switch terminals had the evidence of at-home rewiring and at least one pot had also been replaced – with a shorter, splined shaft that would have never been installed by Fender in a Telecaster. The course of action was obvious: Rewire the rewiring with all new control components.

And while I was in the guitar anyway, I’d fully shield the cavities with copper. While a black conductive ‘paint’ had been applied by Fender, copper simply has a much lower resistance and far better path to ground. Yes, aluminum can also have its benefit as it relates to rheostats (light dimmers), say, so a hybrid of metallurgy may be entertained, as well. The black conductive paint is still very good for the wiring tunnels that are less accessible (applied with a Q-Tip), but the open cavities can always benefit from the copper treatment.

By the way, in tests I conducted some years ago, when using ‘Noiseless’ pickups (such as in this guitar), there was no audible or measurable advantage to using shielded wiring within – when the body cavities were fully ‘potted’ - or shielded. Naturally, I’m speaking of solid body guitars. My hollow-bodied Gibson Byrdland is another animal.

THE PARTS

Here, I wanted to be respectful to the original guitar. With this, I would use two CTS potentiometers for both the volume and tone circuit. While they’re generally regarded as being “all the shit” in the guitar world – generally preferable to Alphas, say, guitar pots are – as a genre – ‘adequate’. As it relates to audio applications, there are far better pots out there – in terms of construction, precision, tolerance, linearity, and longevity ...

 

Really think the CTS pots are all the shit? Think again. The exteriors shown here are quite reflective of their respective interior builds.

But, again – particularly as one who swaps out pots every 3 years in any event – I chose to remain respectful of this Fender Custom Shop instrument. Two 250k audio taper pots from CTS were selected – with the tone pot being of the ‘no load’ variety. Actually, a small array or the pots were measured, from which two were selected. Most measure lower than stated value.

As to the 5-Way switch, Fender was still using the generally excellent CRL switches in 1996. I located one (along with most other parts) at www.specialtyguitars.com … I always preferred these switches to what Fender would use in later years, having a more defined detent in each position. Yet, many Strat players, in particular, seem to like the more vague switch feel of the newer switches. Me, I’m a CRL man.

From here, poly film capacitors were selected – along with a single resistor – to adjust the linearity of the volume pot for a more consistent upper register at all volume settings, as well as the appropriate values for the ‘no load’ tone circuit.

For those not familiar, the construction of a ‘no load’ pot simply scrapes away a small section of the carbon element at the end of the tone pot’s travel. This essentially takes the control “out of circuit” and offers a little more top-end – or bite – at full rotation.

I chose to modify the volume pot response – more as a ‘matter of form’, as I most commonly record at the 75% ~ 100% pot position where this modification would yield the most negligible of influence.

 

These would be rather standardized values. The added components to the volume pot keeps the guitar's tonal character more even throughout its rotational range. Consider it a refinement - not a must, though can certainly be useful when one 'rolls the pot' for dynamic swells. Values may be played with, naturally. Here, both pots would be of a 250k value.

The wire … Here, I use a 22 gauge solid core for the point-to-point wiring behind the control plate – and the stranded core variety for wiring that leads to the control plate, inclusive of any ground wiring … I completely toss the ‘string wire’ used from the underside of bridge plate (compressed against the wood) to the control plate. It’s uninsulated - not so much as a lacquer coat – and can so easily touch the ‘hot side’ of things, even as you reinstall the control plate. So, a stranded – and insulated piece – is sent from the bridge plate cavity (below the bridge pickup) and sent over to the control plate section in place of the ‘string wire’. Naturally, the pickups are already equipped with stranded core wiring …

I used solid core for the point-to-point wiring at the control plate principally because it’s “shapeable” and becomes it’s own, rigid wire-management system. Neat. Clean. Easy to trace back should something ever go amiss.

One may use any brand of wire for this application – even the ‘reprocessed’ wire they sell at Radio Shack in three colors, as the spectral audio signature of an electric guitar is not one of high-end refinement, in any event … But … as it relates to the solder …

Okay … I know you’re going to get your solder at Radio Shack, anyway. It’s so conveniently around the corner. But let me state, flat out, that – in more recent years – it’s probably the worst solder I’ve ever encountered. It’s as if its core isn’t rosin, but contaminant. You can keep on resoldering the joint – or try – but once the joint is dull, you really have to remove the solder – not simply ‘add more’ to get a clean joint.

But given that you’ll likely use the Radio Shack variety anyway, make sure all connections are really clean – even sanded – before you make your approach. And yes, sand the back of the pots where you make some ground connections – being real careful not to get any sanding debris in the pot. In fact, mask off the open aperture near the terminals – along with any smaller holes you may see to the sides. Use a new, package-fresh soldering tip – properly tinned and heated fully. All of this, no matter what solder you use …

But I would advise some other brand of solder, in any event – Weller, whatever. Most anything other than Radio Shack. Make it a light solder – you’re not doing pipe welds, remember. That designed for circuit boards is fine – yes – even for switches and pots.

As to the ‘added switch’ on the control plate – it’s a mini SPST, two-terminal switch. Here, you may pick that up at Radio Shack. Their simple switches are perfectly fine. As used here, it’s the one that comes with four colors of switch covers (that I don’t use, keeping it chrome).

As to the copper tape, I get this from www.stewmac.com … The adhesive back is miraculously as conductive as its front – much better than the black ‘conductive paint’. And, if applied correctly, I have found no need to solder the seams across the tape overlays. Not for years. I use both the 2” variety, as well as the ¾” size for the sides of the body cavities. The ¼” size is useless unless you want to wrap your pickups – not at all advised as it will alter the sound of the pickups … significantly.

Aluminum tape (at any hardware store) may be used in conjunction with the copper variety – particularly on the underside of the pick guard, if desired. Think of a layered hybrid. Any order in the layer is fine.

 

Copper tabs that extend to the top of the guitar surface meet their metalic companions at the underside of the pickguard and bridge plate (containing the bridge pickup). It's not actually necessary to fully shield the pickguard's underside - just enough to create 'enclosed boxes' where the pickups live.

See the stainless screw at the bottom of the bridge plate well? That secures a new stranded and insulated ground wire - replacing the stock (and naked) 'string wire' that's merely compressed between the bridge plate and wood.

HOT TIP: Top the copper tape off with Scotch brand packing tape (not the cheaper off-brand, drug store equivalent). It will prevent any curl-back of the copper tape and - as it relates to the narrow control panel 'slot' - it will prevent your hot wiring from touching ground. Just remember - keep the extension tabs on the guitar's top surface naked. They have to make an electrical connection to the pickguard and bridge plate.

Also provide a small cutout in the copper tape where the screws attach the pickups to the pickguard - while also having some copper way from the pickgurad aperture at the neck pickup. You don't want that pickup's metal shield (on the Tele) to make contact with any copper. Trust me.

THE FINAL ANALYSIS:

Upon the completed component swap and rewiring, I compared the guitar’s residual noise to that of a fully shielded ‘dummy circuit’ that replicated the load of the guitar. Upon jack insertion – and cranking the amp up to full tilt – the only detectable noise component was in the amp, itself. At more reasonable recording levels, the combo was so quiet, residual room noise would become the larger issue. And for direct injection – through an amp simulator, say – there simply was no issue. Indeed, the guitar had gone … ‘digital’. For all practical purposes … noiseless.

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