Shielding a Guitar

[newey]

Any grounding would be through my body to the bridge. I'm mostly water, so it should be adequate.

I'm dubious. A poor substitute for a wire to the jack, the way shielding would be grounded.

I suppose completely surrounding the PUP might make a difference,

Yes. You can never completely surround it, since the pup will need to be open under the strings (or tone will definitely be affected). But the more the merrier. The whole idea is, more or less, a Faraday cage around the pickup(s).

but I doubt it would be much different with a thin sheet of foil.

Faraday used an open wire mesh in his original experiments. So long as the openings are smaller than some multiple of the wavelengths (and no, I don't have the formula at my fingertips) one wishes to exclude, there will be an effect.

I think D2o's methodology, where he tested the same guitar (same room, same amp, etc) before and after a proper shielding job, is more likely to be valid.

[ozboomer]

Apr 25, 2013 23:20:37 GMT -5 newey said:

I think D2o's methodology, where he tested the same guitar (same room, same amp, etc) before and after a proper shielding job, is more likely to be valid.

From my (admittedly limited) experience (of 2 or 3 years of continuous experimenting), I would say that (unfortunately), there is no substitute for actually getting your hands dirty and cutting timber and/or breaking/making electrical connections.

Whilst we all have differing levels of knowledge/expertise in different aspects of the 'guitar' subject, the theory is only ever an indication of something -- when it comes to how YOU feel something sounds... how YOU measure a signal level... what hardware/software tools YOU use.... the theory is (almost) irrelevant...

For example, you'll find examples like this current discussion (about shielding) is just the same as discussions about capacitor types affecting tone, whether cast tremolo blocks sound 'better' than 'forged' blocks, whether THIS guitar wood sounds 'better' than THAT guitar wood... etc.

In my case, I found that a lot of things that people talk about (like the degree of shielding 'effectiveness'... capacitor types, etc) is governed by what 'people' SAY i SHOULD think. For example, I've never been able to tell the sonic difference between 'basswood' and 'alder' in a guitar body... but then, I've not had the same fittings ripped all off the 'basswood' body and re-installed on the 'alder' body and things have been finished (paint) exactly the same. More particularly, it's not something MY ear can differentiate.

On the other side of things, I always thought people talking about AlNiCo pickups sounding 'better' than ceramic pickups were full of bunkum... but that was back in 2006 or so, when I'd not done much experimenting with simple pickup replacements. These days, I CAN say, with some confidence, that to MY ears, I prefer the sound of SOME AlNiCo pickups over other ceramics... but that's MY preference, for the type of music I play... and there is no absolute.

So, people will talk about the effectiveness of shielding to various degrees.. but often, the situation is not fully specified (my thin kitchen foil shielding is not comparable to your thick copper shielding in the same model guitar)... and you can't try and shortcut the work involved by calling on theory -- whilst we understand the CONCEPT of the Faraday cage, etc how such a thing is implemented in a particular environment is likely to *always* be different to what pure theory tells us.... and will be different to what someone else has achieved... you're just gonna have to try it out and see what you find works for YOU and YOUR gear... and realize it might end-up a 'waste of time' (which it never is, 'coz you always learn SOMETHING from these projects).


John

[D2o]

I think that if you don't go about this trying to honestly prove that something works, or at least go about it in an unbiased manner, you're wasting your time.

I am encouraged by your gesture of actually trying something, and would genuinely appreciate your comments based on an honest and genuine effort to properly shield a stock strat-style guitar with traditional single coil pickups (no aftermarket noiseless, stacked SC, etc. etc.).

In my experiment, I was trying my damdest to prove someone's claim. Ultimately, I could not prove it ... but at least most everyone here is confident in the results.

If you don't already have a crappy strat-style guitar, do what I did ... buy a cheap one on Craigslist, do some shielding and wiring experiments on it, then sell it for what you paid for it.

Audio recordings of before and after would be very helpful in terms of deciphering real world results. Basically, when you are doing what you are supposed to do with the guitar, does the darned thing create less noise and hum after than before?

Cheers,
D2o

[Deleted]

sorry for re-iterating myself, but wouldn't measurement/recording of hum *next* to the same exact intense source of hum (e.g. laptop) magnify both the hum before and any possible benefit after proper shielding, therefore minimizing the error in the final calculation?

[Deleted]

Apr 26, 2013 7:01:32 GMT -5 D2o said:

I think that if you don't go about this trying to honestly prove that something works, or at least go about it in an unbiased manner, you're wasting your time.

+1

[gckelloch]

Ok, I did another test using a spare Wilde MicroCoil SC PUP. It's not a noise canceling design, but very low noise compared to it's average potential voltage generation. I used a different analysis plugin at full screen resolution for better viewing. Unfortunately, I inadvertently pasted a few of the graphs over the other ones in MS Paint, so the frequency scale is off screen on those, but the results are still in view and you can use the unshielded graph as a reference. The peaks are represented by the tiny purple dots above each vertical red line. Those peaks are the values to consider. The graphs are in the same folder at the link I provided above.

This time, I used 16" alligator clip leads to connect the ~8" pickup leads to my 8' BL-150 guitar cable. I twisted the leads and set the pickup facing away ~1' from my LED screen, which is on a desktop power strip unit. I moved all metal objects away and took the first screen capture.

For the next capture, I encased the pickup in the heavy duty foil and clipped the ground clip to it. You'll notice that the 180Hz harmonic dropped ~3dB, but 60Hz did not change. That could be pretty useful depending on the preamp gain. There shouldn't be much change at all in pickup tone with such a thin Al shielding, so it's probably pretty useful.

The last capture was done with the pickup encased between two Al pie pans with the ground clip connected to a pan. You can see the 180Hz harmonic drops another ~3db, as do drop some higher harmonics. You'll also notice the 60Hz goes up a bit, which could have to do with eddy currents created by the vertical alignment of the thicker Al. At that thickness and surrounding the pickup, there would probably be a significant adverse affect on the pickup tone as well. I think the eddy currents cancel some lows and highs, so it sounds thinner, but that would require some experimentation to bare out. However, you might find the hum and upper-mid reduction an Al pickguard would provide to be quite useful. Mr. Lawrence has recommended such a pickguard.

As I've mentioned, a few companies sell Al pickguard sheilds that will provide a little upper-harmonic hum reduction and some midrange "sweetening". You could easily experiment with layers of Al tape around the pickups on top of the pickguard b4 settling on a certain thickness to mount underneath it. That's what I did. I choose 8 layers. YMMV.

[newey]

We can't see anything, because you didn't include a link to your results . . .

[D2o]

It is included in his link from a few posts back.

drive.google.com/folderview?id=0Bx0CnqsQz_uYblRTLTQwam5FS2s&usp=sharing

[sumgai]

I think I can safely say that ChrisK would've approved of the direction this thread has taken..... although it's a sure bet that he would've "forced" it to happen sooner rather than later.


gc, you've been fully 'sucked in' to The NutzHouse, you're speaking right to the very heart of why the GuitarNuts and GuitarNuts2 websites were founded, the fact of unbearable hum getting in the way of one's musicianship. Just for sticking with it and not buckling under when someone questions you, I'm gonna have to issue you a +1

And it hasn't escaped our collective attention that you've remained civil throughout the discussion, we thank you for that too. Très cool.



sumgai

[gckelloch]

Thanks for the props, sumgai. I figured the best thing to do is show the results of some experiments. I have made some conjectures based on them, and I have a few more.

I decided to redo and replace the shielded examples for easier comparison. This time I wrapped the PUP in a cloth so the shielding would be held away from the PUP at a distance resembling that of a PUP cavity: ~1/4" from the coil.

The results look pretty similar, but for a more pronounced peak at ~5kHz. Still, it's below -93dB, so...I suspect that has more to do with the placement of the wire around the PUP or something like that. You can see it's now the foil shielding that has the highest peak at 60Hz. It's very hard to get everything situated the same in each example. Move a wire, shift the PUP or shielding a tad and the results change a bit, but there does seem to be consistent reduction at 18oHz with the shielding.

To spare yourself some hassle, I still say skip the PUP cavity shielding and opt for the Al pickguard shielding. If done with care, I don't think PUP cavity shielding would hurt though. I believe Mr. Lawrence said the Al does not need to be grounded. When preparing the experiments, I did notice that grounding it made no difference in the levels.

[ozboomer]

Apr 27, 2013 19:06:04 GMT -5 gckelloch said:

...I still say skip the PUP cavity shielding and opt for the Al pickguard shielding. If done with care, I don't think PUP cavity shielding would hurt though.

I've done exactly that before today... and have found that you can hear a bit of noise/hum improvement with just the pickguard shielding (being done with 'heavy duty' kitchen foil).

...but to MY ears, there is certainly a greater improvement with the cavity treated (whether it's done with the kitchen foil OR with 2-3 coats of shielding paint) AND if there is a connection made between the pickguard shielding and the cavity shielding... and the whole 'cage' is grounded.

...but as always, YMMV... particularly, depending on your environment, the pickups, etc.

[4real]

Personally, a quiet guitar is of huge importance to me, I use noiseless pups as a rule...but I tend not to shield my guitars with cavity shilding, but extensive use of shielded cables where ever practical and that works great for me with quiet pickups...

[mikesr1963]

Jun 22, 2009 13:00:30 GMT -5 ChrisK said:

Here's a StewMac link;
www.stewmac.com/tradesecrets/promo/ts0052_shielding

Here's a link for copper tape where the self-adhesive backing is also conductive, so overlapped seams are electrically continuous.

SHIELDING

[col]

Apr 20, 2013 11:48:41 GMT -5 sumgai said:

Alright, I'm making book on who's gonna be the first to set straight the assertions made by gckelloch, above.

BTW, gck, I don't believe I've said it before, so....

to the NutzHouse! ;D


Stick around, I believe the discussion is gonna get lively, but it'll remain friendly, I assure you.

sumgai

Just a test (missing smiley in the quoted post). Appending the image URL with '~original' retrieves the missing photobucket image.

EDIT: Updated by sumgai, on 2/7/20:  I updated the original post to show the latest and greatest smilie, and left this unchanged for posterity.

[ourclarioncall]

So what is the general concencus from those that have tried different shielding methods? If you bought a new guitar tomorrow with no shielding etc, what would you definitely do to get it as quiet as possible ? And anything you’ve tried you wouldn’t bother doing again?

I shielded a Strat body with copper tape years ago . Unfortunately I didn’t realise I had to ground it. Oops.

I wanted to try the star grounding thing but have never done it yet. I like the idea of taking all the grounds off the back of the volume pot for starters

I have been watching various vid on YouTube, reading (including “shielding the beast”)

Here is two related articles. The info is probably not new to the veterans on here but seems like an okay overview for newbies

www.premierguitar.com/articles/27021-mod-garage-how-to-shield-single-coil-pickup-covers

www.premierguitar.com/articles/27021-mod-garage-how-to-shield-single-coil-pickup-covers

[thetragichero]

I've found that Nashua brand aluminum tape for heating ducts had conductive adhesive and seven bucks will get you a roll that'll probably last a lifetime. much cheaper than copper. I'd use all that (i do not like mixing metals because when you add moisture and salt (like from sweat) you basically create a battery. lots of gnarly gunk
I've tried individual leads to one star ground and it's just too many wires. i don't even use a single star ground in amp builds, preferring star grounds for each power supply node and then a buss linking them all together

[newey]

I've tried individual leads to one star ground and it's just too many wires.

^^^^^^^ This ^^^^^

I have used a buss fashioned from a strip of metal to avoid that problem, on the last couple of projects I did. It's screwed into the side of the cavity at each end and when the sldering is done, a strip of electrical tape keeps it isolated from any hot leads after everything is reassembled.

I sprung for a roll of the fancy Stew-Mac copper tape with the conductive adhesive. I still have quite a bit left after 3 guitars. I didn't think the copper would make a difference, necessarily, but the conductive adhesive is the way to go. (I didn't know about the type of Aluminum tape Trage uses, and the Stew-Mac stuff was the only thing advertised as conductive.)

what would you definitely do to get it as quiet as possible ?

All of this may not make a difference, but it might, so once you have the guitar apart, why scrimp on the details? So I shield the pickup cavities and the control cavity, as well as the backside of the pickguard. If the pickguard has the cheap aluminum backside, I peel that off to avoid any possible bimetallic issues like Trage mentioned, before applying the copper tape.

And anything you’ve tried you wouldn’t bother doing again?

After discussion with ChrisK, he convinced me that the run out to the output jack of a Strat-type guitar did not need to be done with a shielded cable, as the original GuitarNuts "Shielding the Beast" article recommended. It's about a 4-5 inch wire run- too short, realistically, to cause any noise (Per Chris). I also do not shield the canoe-style jack cavity on Strat-type guitars- I have done so in the past and had problems as the clearances are too close, and if the jack tip gets turned a bit, it can short to the shielding. The metal plate over the jack cavity probably provides enough shielding anyway.

[frets]

Graphite Conductive Shielding Paint followed by Conductive Adhesive Copper Tape is the way to go.

[ourclarioncall]

Great feedback , thanks guys 

what about shielding single coils with copper tape ? Or partially shielded 

or shielding the pickup covers on a Strat on the inside ?

also, would multiple layers of copper shielding on the pick guard and cavities make a difference in comparison to just one layer ? 

also , what are the main causes of noise ? I hear a lot of terms like EMI, RFI, 60 cycle hum etc.

is there any clear explanations on GN2 in the archives that could explain to a newbie for example ... 

One  problem is  (EMI) 
The definition of EMI is ....
EMI manifests itself by ...
Here is a solution to the problem that fully or partially addresses EMI

same for 60 cycle hum

[frets]

Do not under any circumstances wrap your coils with copper. If the pickup coils are not shielded, and a lot of standard Strat pickups are unshielded (and a lot of boutique pickups are as well,) Shield the Pickup Coil with “pickup coil tape” that you can buy at a Luthier’s Shop online or off of EBay. 3/4” is what I buy. Do two wraps around the coil. Just make certain it covers all of the the coil. All of it. Metal pickup covers can add additional shielding. Brass is supposed to be the best. Plastic metal treated covers can flake, so no China cheapos”. To me, metal covers are overkill.
You can shield a plastic cover but is tricky and if one does it wrong it kills the pickup’s high end. I’d avoid it.

[sumgai]

Wanna go noiseless? At the very same time, wanna go Tone-loss less? Easy - Just snag yourself a wireless mic system!!!! Best investment I ever made, bar none.


Here's what I bought, about 19 or 20 years ago:

They don't make this particular model anymore, the FCC changed the alloted frequency bands for such devices. But new ones, which presumably would be legal, better made, and hopefully better performing, can be had for starting around $200 USD. But I understand... in the UK, where austerity is forced upon the populace by jacking up the price on nearly everything that might be considered "wanted by someone, somewhere in this land", the price can easily go double that (in British pounds, of course). We Nutz have a solution for that, of course.

But essentially, one can go 'round and 'round about this topic, but I'll guarantee you, radio beats them all. Much more expensive, yes, I get that. But for those who demand results, the cost really comes back to you in peace of mind, and the smug knowledge that you're beating the pants off the other bands/guitarists who show up in the same club, and sound noisy as hell. Come on, it'll only take you about 2 months worth of gigs to pay it off. Errrr, you are getting paid to play, yes?!

A reminder for our overseas members: If you want some particular product from America, but the company wants exhorbitant shipping fees, or they simply refuse to ship outside of North America, then let one of us American Nutz know of your dilemma.  Over the past 15 years, several of us have purchased items for overseas members, and shipped them on a personal basis for much less than what some companies want to charge.  'Nuff said.

HTH

sumgai

[frets]

Sumgai,
That’s got to be from the mid ‘80’s to mid ‘90’s. I remember seeing an old video not too long ago where Mick Jones from the Clash was using one when he started Big Audio Dynamite in the mid 80’s. Ha!!

[ourclarioncall]

Sumgai

I’m interested to know more

And being the minimalist I am, getting rid of long guitar leads that get in your way and under your feet and in my case at work , under the wheel of my computer chair, sounds appealing

My “traditional mental block” is kicking in of course as my brain says “how can it sound as good or better if the signals not hardwired through a cable ?”

What WILL a wireless setup like this do for me and what WONT it do? Will I still have to shield my guitar with copper tape etc ?

Thanks

[b4nj0]

I'm using a more recent AKG wireless. At first I couldn't get along with the latency, but I no longer notice it so I figure my brain soon compensated for it. I only paid around $100 for it via Amazon. There was a choice of about four channels so I picked the channel that was advertised by the least number of merchants! The last thing you want is to rock up and find someone else on your channel ... It has a hook up coaxial lead going to the belt worn / strap mounted transmitter and it was hellishly noisy whenever it abraded on clothes or anything for that matter, so I made another using Klotz and Neutrik. Job done. I did buy a replacement cable from Amazon but the fools had wired it incorrectly and it so annoyed me that rather than fix it I sent it back.

Wearing a devil's advocate hat I would like to observe that the tiny antennas these devices invariably have are stupid engineering decisions waiting to get snapped off. Mine is working in the 70cms UHF Ham band (grr!) so a fractal or even a plate antenna for that wavelength can be made small enough to fit inside the device. It only needs to cover a radius of 50 feet or so. When did anyone last buy a cell 'phone with an antenna poking up? When did anyone last see a car remote with an antenna? Car remotes work at the same ham frequencies. I suspect that wireless radio microphones for guitars only have antennas because folks expect to see one to be convinced it will work.

e&oe ...

[sumgai]

Feb 8, 2020 0:02:35 GMT -5 frets said:

Sumgai,
That’s got to be from the mid ‘80’s to mid ‘90’s. I remember seeing an old video not too long ago where Mick Jones from the Clash was using one when he started Big Audio Dynamite in the mid 80’s. Ha!!

I can't tell you when AKG started making these little buggers, but I got mine, used, in 2000 or 2001.  (I suffer from constant CRS, sorry to say.)  It was at the tail end of the FCC's "old" frequency assignment tables, and the new assignments were going to be more restrictive in terms of both power and frequency "channels". Theoretically, I'm not supposed to use this thing any more, it "might" cause interference with other devices that are newly authorized to use the same frequency band. Too bad. Like b4nj0 says, the transmitting range is somewhere around 50 feet, and if you're close enough for my little guy to interfere, then I want to make sure you paid the cover charge at the door! (Actually, even with a fresh battery, I don't think I get more than 40' out, before the signal goes wonky. Probably due to age, or original design, I don't really care.... so long as it works.)

Feb 8, 2020 7:15:36 GMT -5 ourclarioncall said:

I’m interested to know more

And being the minimalist I am, getting rid of long guitar leads that get in your way and under your feet and in my case at work , under the wheel of my computer chair, sounds appealing

My “traditional mental block” is kicking in of course as my brain says “how can it sound as good or better if the signals not hardwired through a cable ?”

What WILL a wireless setup like this do for me and what WONT it do? Will I still have to shield my guitar with copper tape etc ?

Well, you're right, there are pros and cons. Lessee...

Pros:
The first and foremost reason, you've already nailed it - the lack of cables getting in your way (and the way of others sharing the same closed-in space as you).
Tone:  It's absolutely pristine, no treble loss whatsoever.
Range: I've seen a few of them that hit 200', going from the stage directly to the PA board situated somewhere way out in front of said stage. But those cost considerably more, I'm sure.
Frequency selection (channels): It goes without saying that you get more channels on more expensive units. My little bug is actually hardwired for just one frequency. If a whole band wanted to use a bunch of these, they had to buy separate units that were color-coded to different channels. I think there were 8 total available during its manufacturing run, so most situations were probably covered.

Cons:
Initial Cost: Your initial investment should be driven by your wildest expectations.
Frequency selection (or avoiding interference with others): If you plan to play with several others who might end up following your example (and buying wireless kit), then you want more channels.
Range: This will also drive the cost figure. What's the maximum working distance you expect to see?
Continuing Cost: Batteries. Today's units can give 12 to 20 hours of up-time, easily. Mine gives me 9 or 10 hours, which isn't too bad for something that old.
Loss: if your cable goes gunnysack, it's easy to replace it. If your wireless setup goes GeFooey, keeping a spare on hand is way expensive... yet do you go to a gig with only one cable? Perhaps a cheaper unit, just for backup....

Or here's another thought that might justify having two units: One goes from your axe to the first pedal in your chain, and the other goes from your pedal board to the amp. Now you are playing on a truly clean stage! (EDIT: see my follow on post below for more details on this operation.)  Twice the cost, but if a bump-in-the-night occurs, you can use one of your spare cables to replace the soured unit. (You are still bringing along spare cables, yes? Do you really think that a $250 radio is immune from Murphy's Law?!)


On the subject of shielding..... Do it.  Period.  What happens if your new kit goes on the blink?  You're gonna plug in a cable, right?  And if your guitar isn't shielded, what's it gonna sound like?  I trust this answers your question.

But for the sake of argument, I found that my wireless unit doesn't care if the guitar is shielded or not - still perfectly quiet, either way.  But that's been with only 3 guitars over the last 20 years (a cheap MIM Strat, an American Deluxe Strat, and a MIM Jazzmaster).  Others may report different results, and I would not argue with them.... I'd only say to them "And what if you have to plug in a cable? "  Even if they backed me up on the no-hum aspect, I'd still point out that crap happens.

Feb 8, 2020 8:59:43 GMT -5 b4nj0 said:

I'm using a more recent AKG wireless. At first I couldn't get along with the latency, but I no longer notice it so I figure my brain soon compensated for it.

Latency? Never heard of it. But then again....

I only paid around $100 for it via Amazon.

Might be the reason right there. AKG fills the entire spectrum of cost verses features - there's something for everybody at nearly every price point.

There was a choice of about four channels

Probably for the same reason as just mentioned.

Wearing a devil's advocate hat I would like to observe that the tiny antennas these devices invariably have are stupid engineering decisions waiting to get snapped off.

Mine doesn't have this appendix. I haven't even thought of looking closely at the latest and greatest. Do you suppose that this might also be a cost-driven feature (or lack thereof)?

Mine is working in the 70cms UHF Ham band (grr!)

Ahhh, the FCC rears it's ugly head yet again. Part of that frequency re-allocation decision I spoke about earlier.


Getting pretty long here, might be a good time to pack it in.  Have I missed or skipped over anything?

HTH





sumgai

[ourclarioncall]

Sumgai

Thanks for the detailed response

I think the only couple of things that put me off are having a bulky thing hanging off my guitar

And batteries

Would it be possible to put one of these things inside the cavity of the guitar to get it out the way or rout an area for it to dwell in?

And as far as batteries , maybe a super duper long lasting battery that could be charged via usb cable or something

Also, would you say it’s possible a normally noisy guitar would not have the same noise using one of these gizmos? What type of noise specifically would it be immune from?

Have you had a glance at the current options on the market today for one of these wireless things ?

[sumgai]

Feb 8, 2020 15:21:40 GMT -5 ourclarioncall said:

I think the only couple of things that put me off are having a bulky thing hanging off my guitar, and batteries.  Would it be possible to put one of these things inside the cavity of the guitar to get it out the way or rout an area for it to dwell in?

Yep, done all the time. The radio itself need not be very large, so it will likely fit within a Strat's cavity.  A Les Paul-style axe, that might be another story, I dunno.  As far as batteries go, that's easy.  Guitar Parts Resource.com has a page full of different sizes and shapes, for many different requirements.  An example image:




Plenty of other places to shop, if that one don't ship to The British Isles. Or take advantage of my previously mentioned offer of one of us Nutz helping you out.

And as far as batteries , maybe a super duper long lasting battery that could be charged via usb cable or something

newey once posited this idea, using a cell phone battery. (Nominally a 3.7 volt jobbie, so more than one might be needed.) Sadly, there'd be no pre-built casing for this kind of thing, like for standard AA cells and 9 volt batteries. The main advantage of a cell phone battery would be that it could be recharged time and again, but where does one find a stand-alone charger? Re-chargable AA cells don't cost much more cost than standard cells, but they must be pulled out and put in the stand-alone charger.... unless you do some more routing for installing the charger as well. Running a 220 volt line to your axe is what I'd call a "not very good idea", I'm sure you understand.

Also, would you say it’s possible a normally noisy guitar would not have the same noise using one of these gizmos? What type of noise specifically would it be immune from?

Pretty much all noise that affects a guitar is electromagnetic in nature. The first part of that name implies that a circuit must be complete in order for something to flow. In the case of magnetics, the same ideology applies - in order for a magnet to affect something there must be a complete path for the field to traverse - source magnet -> object -> back to source magnet. Lather, rinse, repeat. The very definition of the word 'field'. (Place some iron filings on a piece of paper, and hold a magnet underneath. See the shape taken by those filings? Looks like an elongated circle, yes? But the circle is complete - no gaps. Voila, proof of a complete circuit.)

Without a lot of laboratory testing, I'd hazard a guess that pretty much all electromagnetic noise is stopped in its tracks. The reason? Seems simple enough - you've interrupted the circuit. Where your body was (and still is) an antenna for all this noise, you were re-radiating that noise into the pickups. The circuit here is exactly like a bog-standard radio - the Earth ('ground') is one half of the circuit for that radiation, and the pickups/cable-to-the-amp are the other half. Since an amp is grounded at the power cable, the circuit is complete. When you touch the strings, you are essentially shorting the antenna (you) to ground.  It's no longer going to the pickups, which means a reduction in noise, if not eliminating it altogether. However, if we place a non-cable signal carrier in the path, where the cable used to be..... Voila! No more complete circuit, hence no more noise. 

Why didn't the noise simply go out over the radio, like it did over the cable?  I'd ask the reverse question - why should it do so? 

Look at it this way.  The radio is an "isolator", just like a transformer that steps voltage up or down isolates one side from the other (primary and secondary).  The way that works is through magnetics, which is what gave rise to the name electromagnetics in the first place (way back when).  Or like a capacitor that can easily conduct AC, but not DC - it is isolating one stage from another when it comes to the power supply voltages, but it's not isolating the signal itself from getting through.  Same thing happening here, and we don't have to look too deeply to find the explanation.  In essence, the MOJO comes from the fact that the radio is swamping the noise level with a much greater signal.  If you look hard enough, the noise might still be present, but it's now at such a low level that it'd take some quite sophisticated equipment to detect it.   Your amp does not have that level of sophistication, trust me.  

And whatever noise did get carried along from the transmitter, the receiver is well equipped to detect it, and further reduce it to nothingness.  But here again, we see that the cost of these combined units (transmitter and receiver) will determine the ability to scrub the noise from our desired signal.  Before we settle on something that looks good on paper, we should be able to return it to the store, in case real-world testing doesn't prove to be what we wanted in the first place.

I can image a very poorly made pickup that has almost no signal level output, and is extremely receptive to outside noise and hum.  Such a pickup might cause a wireless mic to sound like it's not doing its job.  But if wireless mics usually work exceptionally well, then I'd point to the pickup itself as the culprit in such a case.



I'm not saying this is absolutely fool-proof all of the time, but in most cases it works just like it says on the tin.

Have you had a glance at the current options on the market today for one of these wireless things ?

Sorry, not in my current purview. Research of this nature must needs be left to the ardent researcher, not to the arm-chair quarterback.



There, see? I'm once again into scribbling a veritable treatise on a topic. Keeping it short and sweet just doesn't seem to be my forte these days. Gahh!

HTH





sumgai

[ourclarioncall]

Sumgai

I’m a details guy so I like lengthy posts. And often you would be as well answer the questions that you know will probably be asked eventually by curious minds like mine 😊

So how far has anyone on here taken these ideas ?

Is there now way you could gut out an old iPhone or something and use the case to hold the battery. Then you could just charge it like you charger a normal iPhone ?

Also , I don’t know if this other pic is what you meant by standalone charger , maybe tech had come on since y’all kicked these ideas about

[sumgai]

occ,


Those stand-alone chargers for 3.7vDC cell-phone batteries are exactly what I'm talking about. And of course, there's a BIG caveat in there: they plug into a wall socket. If you somehow shoehorn a charger into your axe (besides giving up a lot of ToneWood®), you'll essentially be plugging your guitar into a wall socket - is this really a good idea in your book?   I suppose a person could jury-rig a Rube Goldberg type of safety device, but that seems like overkill to me.

More or less, the same holds true for a gutted phone's case - you're gonna be hogging out more wood than necessary.  And at that point, you won't be removing the guts anyway - the charging circuit is part and parcel of that circuit board, so you might as well leave it intact.  Unless you're an extreme hobbyist in hacking phone circuit boards, that is.   Just be sure to disable the connectivity options before battening down the hatches!

No, I'd stick with standard batteries, or rechargeable ones, and plan on flipping up the lid on that battery compartment every so often to swap them around.  Easier to implement, less costly over the long run, and requires the least amount of wood removal.  

The only drawback to all this is that if you do decide to stick everything under the covers, then what happens if you want/need to upgrade, and the drop-in replacement isn't the same size?  That's right, you get to hog out even more wood.  Over time, this may not seem too much of an obstacle, but if you're like me, you want the latest and greatest now, not some time down the road when your current kit has kicked the bucket.  That's exactly why I haven't inserted my Guitar Bug.  Besides the portability factor, that is.  (Recall that the same Bug is now on its third guitar, and none of them had any work done to accommodate the thing.)  (Oops, I forgot... I also used in on my Jazz Bass for several years, so make that 4 guitars for me.)  Yes, it has turned out that the Bug has been my only radio, I've never actually contemplated upagrading just because I could.  But that's a rarity for me.

Now, if you're willing to Velcro an old (and working) cell phone to the back of your guitar, then that's a different story.  But in point of fact, you could hack it only insofar as needing to access the microphone's input (there being no MIC input jack on these things), and hook up your guitar's output to that point in the circuit.  Then you could simply Bluetooth the guitar's signal to anywhere you like - even another cell phone that has its headphone jack cabled directly to the amp's input!!  Same thing as a designed-for-guitar unit, but much less expensive.

The sky's the limit on these kinds of things.

HTH


And no, I need to simplify.  I hung up my professor's hat 20 years ago, and it doesn't fit any more.  Pontification is for the next generation, I'm done.




sumgai

[sumgai]

Following on to my post above about using a second radio to run from your pedal board to the amp....


When I was active in the biz, I went down to Radio Shack ('cause it was still around back then) and purchased a couple of 8-cell battery holders. These took 8 AA cells* and made them into a 12vDC battery. Strangely, the output connector was a standard 9-volt setup, the polarized kind that had a grip like iron. But the receiver for the Bug uses 12vDC power, so instead of a wall wart, I could slap this thing down right beside the receiver, plug it in, and power up the receiver for maximum goodness! (Recall that the transmitter has its single AA cell built in.)


In this manner I truly had a cable-free stage presence.


I can hear you asking now....  "Why did you buy two multi-cell holders"?  Lemme ask you once again.... do you take along at least one spare cable to a gig?   If I've gotta take 8 spare batteries anyway, and have to put them into some kind of container, why not just prepare them for use ahead of time.  Plug-and-play at its finest.

HTH




sumgai

* The proper name for a single cell battery is "cell", and more than one cell in a casing becomes a "battery". But Marketing being what it is, the general usage has been perverted to mean that 'battery' means both cells and batteries.