eliminating noise!?

[brads4]

I just did a test on my "noisy" presets; I unplugged the guitar cable from the Axe FX to see how much noise was really being generated by the amp sim.
The answer was practically zero for most amps; on some there was a gentle hiss. My conclusion is that amp noise reduction is NOT required but adequate shielding and cabling is.

However, if you stick a m-zone in front of a FAS Modern II then you will get a heap of noise. Personally I just wouldn't do it!

If you plug my guitar into your rig, you would hear no change in the noise levels from no guitar input at all. I can barely hear the mesa lead channel of my Mark IV with gain at 8, lead drive at 8, both pullphats out and my guitar maxed vol and tone. I really should record what it sounds like with an unshielded guitar with bad wiring and my recent wiring upgrade.. Just remember, that every diagram online is totally wrong, when shielding is added to the equation.

 

[pauly]

G'day again,

I know what you mean - hard to fathome there's really a problem when you've solved it in one instance
Let's say you've been called up to go to some little backroom studio, and there's some airborne electrical noise such as from a distribution transformer next-door, or the aforementioned light dimmers, or a squillion and one other reasons for electrical noise.... This will impart _some_ noise, even on your well sheilded guitar. As an example, I have a rewired Telecaster (single coil pickups) that has earthed copper foil lining every cavity - even the scratch plate. In my environment it's _acceptably_ noise free but certainly not noiseless. My guitars and basses with humbuckers are much quieter, but this telly sounds excellent so it's not getting changed!....
So... A track is recorded, and though it's relatively quiet, it's going to impart some noise into the finished track - particularly if it's used on (say) 2 backing tracks, and a harmonised, double tracked solo (suddenly there's 6 guitars on the recording.

Now - as a recording engineer, I'd be a dunce not to minimise the noise on each of those tracks so the quiet parts of the song are in fact quiet - This is where good noise reduction plugins are useful. Sure gates are used where the instrument is not playing, however gates arent suitable to remove noise in many situations. So.. the plugin takes a sample of that noise, then uses digital magic to remove it from the track.
They work well - particularly the expensive ones (I have a few).

So - If that was included as a block in the axe fx - I'm absolutely sure it would be useful for some. The price would of course be that each room, each guitar, and in some cases each session, the noise is different so the learning and applying of the filter would become part of the standard 'setup before playing' routine - along with tuning etc.

Once again - I agree that it would be nice to have noiseless gear all the time - but It's not always possible. This is particularly true when you are recording other peoples instrument (they dont want you messin with it!)

Anyway - that's just my take and I'm not the only guyu with an opinion.

Thanks
PAuly

Am I wrong to assume that completely properly shielded guitars will in fact not get any noise??? I know I certainly am picking up no noise at all in my recent recordings with my first perfectly shielded guitar. And I'm talking about checking at super high gain. Perhaps I am missing something, but my entire signal chain is protected so room hum doesn't make it in, unless you are talking about the actual pick-ups grabbing room noise... I dunno. I don't see why it can't be solved at the source. ? I don't mean this to be argumentative, I am genuinely interested.

 

[brads4]

G'day again,

I know what you mean - hard to fathome there's really a problem when you've solved it in one instance
Let's say you've been called up to go to some little backroom studio, and there's some airborne electrical noise such as from a distribution transformer next-door, or the aforementioned light dimmers, or a squillion and one other reasons for electrical noise.... This will impart _some_ noise, even on your well sheilded guitar. As an example, I have a rewired Telecaster (single coil pickups) that has earthed copper foil lining every cavity - even the scratch plate. In my environment it's _acceptably_ noise free but certainly not noiseless. My guitars and basses with humbuckers are much quieter, but this telly sounds excellent so it's not getting changed!....
So... A track is recorded, and though it's relatively quiet, it's going to impart some noise into the finished track - particularly if it's used on (say) 2 backing tracks, and a harmonised, double tracked solo (suddenly there's 6 guitars on the recording.

Now - as a recording engineer, I'd be a dunce not to minimise the noise on each of those tracks so the quiet parts of the song are in fact quiet - This is where good noise reduction plugins are useful. Sure gates are used where the instrument is not playing, however gates arent suitable to remove noise in many situations. So.. the plugin takes a sample of that noise, then uses digital magic to remove it from the track.
They work well - particularly the expensive ones (I have a few).

So - If that was included as a block in the axe fx - I'm absolutely sure it would be useful for some. The price would of course be that each room, each guitar, and in some cases each session, the noise is different so the learning and applying of the filter would become part of the standard 'setup before playing' routine - along with tuning etc.

Once again - I agree that it would be nice to have noiseless gear all the time - but It's not always possible. This is particularly true when you are recording other peoples instrument (they dont want you messin with it!)

Anyway - that's just my take and I'm not the only guyu with an opinion.

Thanks
PAuly

That is exactly a great answer, and I really appreciated that excellent comment! Everything you say makes complete sense! I appreciate such a well thought out and useful answer. It's much appreciated. Your opinion seems extremely reasonable and backed by a lot of experience. I will certainly be listening for these types of things in the near future while working on recording projects (I am just an amateur, but I record my band). These are good things to think about.

 

[Rex]

The smart thing about the plugins I mentioned is that they take a 'print' of the unwanted noise and remove that from the signal. That doesn't mean there aren't artefacts but the user can decide to what extent the reduction is applied.

Noise plugins can reduce interference—at a cost in signal fidelity—but they can't touch noise (remember what Cliff posted about the difference between interference and noise).

Interference is somewhat predictable in a given situation. If you look at the graphs that are displayed in the plugins, they plot amplitude against frequency. In other words, they represent EQ. And when you apply that processing to the interference, you're also applying it to the signal, because both are riding in on the same wire. You can reduce the interference, but you're also changing the desired signal. It's a trade-off, and a good "noise" plug-in lets you decide how much fidelity you want to trade away to reduce the interference.

Noise, on the other hand, is a series of random events. You can measure the random events, but you can't use that knowledge to predict future random events, so you can't take out the noise.

 

[Rex]

Regarding noise reduction in the guitar itself (it's actually interference reduction; you can't touch the noise):

In a guitar, the currents are so small and the grounding resistances so low that ground loops in the guitar itself are a non-issue. The real benefit comes from proper shielding.

In fact, relying on physical contact between the pots and the shielding can make the problem worse. You're better off soldering ground wires between all the hardware.

 

[pauly]

Thanks!
Pauly

That is exactly a great answer, and I really appreciated that excellent comment! Everything you say makes complete sense! I appreciate such a well thought out and useful answer. It's much appreciated. Your opinion seems extremely reasonable and backed by a lot of experience. I will certainly be listening for these types of things in the near future while working on recording projects (I am just an amateur, but I record my band). These are good things to think about.

 

[brads4]

Regarding noise reduction in the guitar itself (it's actually interference reduction; you can't touch the noise):

In a guitar, the currents are so small and the grounding resistances so low that ground loops in the guitar itself are a non-issue. The real benefit comes from proper shielding.

In fact, relying on physical contact between the pots and the shielding can make the problem worse. You're better off soldering ground wires between all the hardware.

I disagree regarding soldering to the pots. Most people have garbage soldering irons, and the heat required for a good connection often can damage the pots, or create cold solder joints (almost always). You need high quality soldering equipment to do it right, and most don't have it. I prefer the shielding ground, not sure why you would consider this less reliable, but I can't see any way this will be an issue. It's nice thick copper tape, and i test continuity with a multimeter.

The other point, I have heard the same thing before, however I have had others swear it makes a difference having only 1 path to ground. I'm going to wire up a second guitar with the exact same config, pickups, pots and caps, but with the addition of solder to the bottom of the pots (I have a good solderoing iron that can do the job correctly) and do an A/B on the signal to see if there is any noticeable difference in noise levels.

Thanks for the info, the more you know the better

 

[Rex]

Most people have garbage soldering irons, and the heat required for a good connection often can damage the pots, or create cold solder joints (almost always).

Some people don't keep their tips clean. With the tip cleaned and tinned, even a cheap iron will do the trick. In any case, if your solder joints aren't good, interference isn't the only signal problem you're going to have. The soldering has to be good, no matter whether there's shielding or not. And the only acceptable fix for a bad soldering job is a good soldering job.

Solder is a more reliable electrical connection than mechanical contact between dissimilar metals. That's why it's better than pressing a steel pot onto copper foil. Reliable electrical connections are the only reason we use solder in guitars.

I have heard the same thing before, however I have had others swear it makes a difference having only 1 path to ground.

It only makes a difference if you have sloppy, high-resistance solder joints, and those must be fixed (see above).

 

[brads4]

Some people don't keep their tips clean. With the tip cleaned and tinned, even a cheap iron will do the trick. In any case, if your solder joints aren't good, interference isn't the only signal problem you're going to have. The soldering has to be good, no matter whether there's shielding or not. And the only acceptable fix for a bad soldering job is a good soldering job.

With my 40 watt iron, clean, new tip, tinned, I still have issues creating good joints on the top of pots. I've rarely seen good ones in my experience, which leads me to believe most people are doing it wrong, or most irons are not suitable for this task, or a health combination. Maybe you are better at soldering than most, but I am decent at it (not a pro!) and still have issues with that particular joint. I also read that excessive heat will often damage pots and pot lubricants, which is often necessary to head the pot hot enough to create a good joint. (due to the size of the pots)

Solder is a more reliable electrical connection than mechanical contact between dissimilar metals. That's why it's better than pressing a steel pot onto copper foil. Reliable electrical connections are the only reason we use solder in guitars.

what about using copper locking nuts or something like that?

It only makes a difference if you have sloppy, high-resistance solder joints, and those must be fixed (see above).

Which is mostly what I see when working on people's gear.

I appreciate the insight! Thanks.

 

[DavezHear]

Not surprising really, most pots are not really designed to have the cases soldered. Often nickel plated, they can be hard to solder brand new as the nickel will still look shiny but still be oxidized. The key will be soldering speed, you may need to mechanically clean the surface to be soldered to get the solder to wet quickly enough so you don't damage the internals. Bare copper hardware will oxidize fairly quickly and then not give you a reliable connection.

 

[pauly]

A hotter iron (lets say 60 watts) used quickly will give good results without stressing the pot and related compunds too much. Where problems happen, it's usually because someone used a low wattage iron and held it on the pot for waaaaay toooooo looooooong in order to make a decent solder joint - Thereby heating up the whole pot, and evaporating whatever compounds are placed there (by the manufacturer) to lubricate & provide longevity. Soldering pots is like a military operation - the best are quickly executed with as little fuss as possible

Thanks
Pauly

 

[Rex]

With a good, well-tinned tip and a little extra solder, 40 watts is enough to solder to the body of a pot. The trick is to hold the flat of the tip against the pot long enough to make the pot hot enough for the solder to adhere the first time. It's repeated heatings that damage the pot, because that makes the other side if the pot too hot.

I've never seen copper lock washers. Cooper is too soft to perform that function well. You'd still have dissimilar metals (pots aren't copper), and you'd still be relying on mechanical pressure for a good connection. It's bad enough when a pot works loose. It'd be much worse that loose pot also disconnected your guitar.

 

[Soultrash]

hmm, being through all the posts so far it seems like it could be either my guitar or some noise interferrence.
i just ordered a can of shielding paint, as i said the electrnic cavity is painted all over however the cap isn't, maybe
painting the cap will help. otherwise i can't see anythog else i can do, the cable is OK, and it's a pretty decent one
(monstar cables) i also have a VOVOX. my home studio is also noise free, it's really strange. i am alsu using
an amp+cab setup only, no extra overdrive and the gain is fairly low, 5153 red, with gain about 4-5...

 

[Rex]

... the electrnic cavity is painted all over however the cap isn't, maybe
painting the cap will help

Yes. Shield the cavity cover, and make sure that, when you screw it down, it makes electrical contact with the cavity shielding.

i might have a problem with the input jack though, it gut's off the signal when i move the cable around...

That needs to be fixed. If you're sure it's the jack that's bad and not the cable, it's probably a loose connection that needs to be redone and resoldered.

my home studio is also noise free...

If your studio were noise-free, there would be no interference to pick up. Turn off the noise gate. What do you hear? Now, with the noise gate still turned off, unplug your guitar cable from the Axe-Fx. Now what do you hear?

 

[Bodde]

i was just thinking if it would be possible to give us an option/switch that removes/dampens amp noise!?

i am not talking about a noise gate but more something like cliff "coding" the noise out.

as the axe-fx is a digital unit so many things can be programmed, distortion, saturation etc. logically it should be possible to remove amp noise with out altering the amp sound in general, right?

if so, i'd be really glad for such an option, it would make
recording much easier. i mean noise gates work but they surely have their limits...

I actually like your idea. Seems like many people are having issues with noise. There have been many topics about this so it bothers people. Especially when you add distortion or certain amps the noise gets amplified very much and you have to use heavy noise gate settings which don't sound good and kill your dynamics.

Even with a good guitar you have noise. Even with my high end Wal basses I have much noise when I plug in the Axe fx and add certain effects. Don't say it's the fault of the Axe fx. But when you want to add certain effects or distortion noise will arise. Would be great if we could eliminate that. Or at least have some option to choose in the amp. As you say it's a digital machine and the advantage of that is that you could remove it. Maybe at the cost of some of the amp sound. But then it is up to you if you want to sacrifice a bit of amp sound in favor of less noise. I think I would, especially for recordings. Not sure if this is possible but I like your idea and have thought about that myself many times.

 

[Guitar Player]

The direction your pickups are pointing in the room aswell as the position of the guitar in the room make a big difference due to some hocus-pocus you cant see.... seriously. Somtimes when i really care about my recording ill stand up well away from my pc and monitors and it will reduce the noise to almost none.

 

[Soultrash]

so i bought some conductive paint and re-did the electronic cavity and the cavity cap.
i can't hear a real difference though.

in general the guitar is quiet, however when adding a drive before a hi gain amp,
even not adding any distortion but only "tone" the noise is extremely amplified.

on a normal hi gain amp+cab setup i have basically no issues even without the noise gate engaged.

i mean, it's logical that a drive will add more noise, i just think that it was not so present in older FW versions...

 

[Soultrash]

ok, i might have somethig here...

i have noticed that on all my presets the "input trim" is at the default setting.
if i lower the input trim the noise almost goes away completely.

sure i lose some gain, but when adding gain back the noise stays fairly low.
this is interesting...

the input gain is also set at 100%, going down to 50% in combination with a low input trim setting
i am able to get heavy distorted tones without having too much noise.

not sure if this is a "legmtimate" solution but right now it seems to work...

 

[HarrySound]

Depends on your definition of "noise". The correction definition of noise is a random signal caused by thermal agitation of the atoms in a conductor. Any atom higher than zero degrees Kelvin will experience electrons randomly switching in and out of valence states (IIRC). This causes random electron flow in the conductor. The higher the resistance of the conductor the more this random electron flow will induce voltage since V = I*R. This is known as Johnson noise. Johnson noise is proportional to resistance and temperature ( = sqrt(4*K*T*B*R) where K is Boltzman's constant, T is temperature in Kelvins, B is bandwidth in Hz and R is resistance).

Your knowledge is insane!
It almost makes me laugh!

 

[6stringscott]

Interference was killing my sound, making it unplayable... my remedies:

1. Swapped out my stock 1995 Fender Squire (Korean model) pickups for interference canceling Zexcoils. I wish I got the pure stratty sound ones, but I went for the splitbucker to get humbucker emulation. That tone is nice, but the loss of pure 100% strattiness leaves me envious when I hear others. Zexcoil had pickups that do sound good for that sound, but without the humbucker option.

2. I used spray-on conductor paint in the cavity and under the pickguard. You need to use A LOT to make a difference. I measured it with an ohm-meter, and one or two sprays is not enough. Really need it thick.

3. Replaced the stock pots with higher quality ones from Stu-Mac. Also replaced the 5-way selector switch. Turns out that made a substantial difference. I blew the soldering and destroyed the components the first time I tried.

4. I bought an expensive temperature-regulated soldering station, much better than cheap unit, but I still suck at soldering. Even the fancy iron heats up the pot too much before I can get the solder to melt. I even bought separate bottle of flux to make it work better. Maybe the problem is trying lead-free solder? Better for environment, but not better for soldering?

I don't have any noise problems now, but I crave the pure strattiness I lost because of my pickup choice. Zexcoils good, but be careful to get the option that matches the sound you really want.