Resistor and an aluminum neck

[frets]

Hey guys,
Another weird one. I’ve got a guy who wants me to build a harness. He has a Kramer with an aluminum neck and claims there is a resistor on the harness for the aluminum neck. I have never heard of such a thing. Does anyone know what he’s talking about?

[Deleted]

I don't know about this
To me if not grounded you could make the neck in to a variable resistor. Between the strings and neck..

But I'm unsure why a resistor

[newey]

Yeah, I can't see any reason for it either. The Kramer aluminum neck guitars evolved from the Travis Bean guitars (G. Kramer worked for TB before starting Kramer Guitars). While I've never looked inside one, the wiring diagrams for the Beans didn't show any such resistor.

If the bridge is grounded (it is), then the strings are grounded. Unless the shafts of the tuners are non-metallic, then the tuners are grounded through the strings as well. So the aluminum neck would presumably be grounded because the tuners are bolted to it. Adding a resistor between the neck and the harness would still leave the path to ground through the strings/bridge with less resistance, so the resistor wouldn't be accomplishing anything.

The only two possible reasons for doing so would be noise reduction or shock protection, and the bridge ground presumably takes caree of the noise issue just as it does on most guitars. Potential shock reduction/protection would call for a capacitor, not a resistor, and it would need to be in circuit after the string/bridge ground since that pathway remains connected to the neck. I wonder if your guy is referring to a cap such as the 400V cap John Atchley recommended in the original G-Nutz's shielding scheme, but again, that would not simply connect to the neck, it "isolates" (not really, but I can't think of a term for it) the whole harness.

[cynical1]

This is one of those, "you're gonna have to bring it in" moments. If that's not possible, picture of the crime scene are required.

HTC1

[b4nj0]

The resistor must be intended to counteract aluminium's positive coefficient of expansion.

I suppose I'd better get me coat then?

でつ e&oe ...

[cynical1]

Honestly, if the customer has an old aluminum neck, his major issues probably won't be resistor related anyway...

HTC1

[thetragichero]

in some circles aluminum necks are quite popular. new ones cost more than I'm usually willing to spend on a complete instrument (like 800 clams). it's part status symbol and part "this instrument is so metal it's metal"

[asmith]

Aren't all harnesses resistors? They resist gravity.

[frets]

The guy lives out of state. I’ll ask him for a pic. What he told me is a previous guy who installed the neck did this. I’ll get him to send a pic. But I’m in agreement with you all, it would do nothing. But, as we all know, once something is done in a guy’s guitar, they believe it must be done by every future guy (gal in this case). It is magic.

I’ll see if he can get me a pic because I’d love to see what you guys thought.

Thanks😺😺😺

[frets]

Well, this has been solved. He was looking at a treble bleed. After swearing it had to do something with the neck. This is what one encounters in this business. Ha!

But as a side note, I was looking for the Atchley cap ground scenario and could not find it on a search. Can one of the angels point me in the right direction? 😸😸😸Thanks!

[unreg]

Aug 8, 2022 12:54:56 GMT -5 frets said:

But as a side note, I was looking for the Atchley cap ground scenario and could not find it on a search.

In “Guitar Wiring” this thread appeared, but I think it’s matching John Atchley…

guitarnuts2.proboards.com/thread/1474/ground-loop

maybe this post:

Mar 23, 2007 19:45:22 GMT -5 sumgai said:

Dan,

WHOA! STOP!!!!

You did WHAT?

[I] then attached the tremolo ground to one end of the 400 V capacitor and attached the other end of the 400 V capacitor to the hot lead of the output jack

You wanna repeat that?

6) run the tremolo ground to one end of the 400 V cap and the other end of the 400 V cap to the hot lead of the output jack

OK, that's it. Put your hands in your pockets, and back away from the workbench, right now!

I might have let the first instance pass, thinking you just made a typo. But your second iteration isn't a mistake in typing, that's a gen-u-wine shortcoming in your electrical ed-ju-ma-cation.

Short and sweet:
The point of that 400 v, 0.33µf; cap is to isolate the guitar's ground from you, as you touch certain metallic items like f'r instance, the strings. So what's important to me right now is, just where did you "learn" that connecting the cap to the jack's hot lead is the proper method?

Long and drawn out:
What John Atchley is all up in arms about (and there's no conclusive proof that he's tilting at a windmill here) is the fact that under certain conditions, a particular kind of malfunction in a tube amp could lay the B+ High Voltage onto the ground circuit. The time it sits there may be short, but in a worse case scenario, that's exactly the time you'd be touching the strings, and touching something else at the same time, like a mic, or another player, or standing in a puddle of water at an outdoor festival, whatever....... The shock may be short, but it will definitely be no less sharp than any other kind of shock you could possibly receive in these conditions.

John's recommendation for reducing that hazard down to non-life threatening levels is too cheap not to do it. Not only that, he also explains it pretty well on his site, and has some pretty good images to show what he's done, and how to do it.

While I've been rather curt with you on this one, I'm sure you realize that what I'm really in tizzy about is safety, first, last, and foremost. You, my fine feathered friend, are on the way to becoming my dearly departed FFF, should you rely on that wiring for your health and safety any longer than it takes you to open your guitar and correct this mistake.

Aside from all that, it seems to me that you were also introducing a path whereby your body's natural aerial tendencies were being sent directly to the output jack's hot lead...... didn't that kinda cause just a teensy bit of extra noise in your sound, every time you touched the strings? Inquiring minds wanna know.

OK, diatribe over. The rest of your plan looks good to me. Just get past the above deficiency, and all will be well! ;D


sumgai

is what you are looking for?

[unreg]

Hmmm…

Kept searching… in this thread:

guitarnuts2.proboards.com/thread/3197

someone, maybe sumgai, said that John Atchley’s page couldn’t be found in Archive.org bc John Atchley blocked bots from visiting his pages.

a little later in same thread, reTrEaD posted this link:

www.singlecoil.com/docs/shielding_strat.pdf

I believe ^that could be what you are looking for frets.

[frets]

Thanks Unreg, I have it now.

[sumgai]

unreg,


Ya know, I had to go back and read that original thread, being as it was dated 15 years ago.....

Seems I was addressing a newbie at the time, one DD842, later to adopt the screen name of D2o. Dan turned out to become a good friend both on and off the board. He also, like newey, paid attention and learned from the bunch of us who were well-equipped to espouse bits of knowledge when and where needed. Of that core group, JohnH and I are just about the only regulars left, and even I have been known to take long leaves of absence.

Back then, I was posting prodigiously, and most of the time I was pretty much correct. Nowadays, I'm lucky if I can remember my own name when I wake up in the morning. Which would explain why I no longer get into the depths of most technical discussions - I'd just muddy the waters. But I've one word (phrase) for those that think I'm irrigated about this.... I'll just quote cynical1, if you don't mind:

Never regret becoming old enough to judge.... it's a privilege denied to many.   

sumgai

[newey]

There are any number of threads hereabouts that discuss Atchley's capacitor "isolate" scheme. As was often the case, ChrisK's take on it (with diagrams) covers most of the salient points:
guitarnuts2.proboards.com/thread/4187/blocking-capacitor

As one will see from reading that thread, Chris believed that rather than rely on a "blocking capacitor", better to use a wireless system and a GCFI cable, and to check the outlets in any venue where one is playing. Do those things and there's no need for the capacitor.

The failure mode here is typically seen only with vintage tube amps with a two-pronged power cord, and especially with the ones with a two-way power switch. Playing through a modern solid state amp, the risk is minimal. But the cap, as ChrisK notes, is better than nothing. If one plays a vintage tube amp, it should be done. Or even if one doesn't know for sure whether the guitar will ever be used with an old tube amp, better safe than toasted . . .