Noise gate for single coil noise

[aquataur]

Hi Folks,

I have up till now used a multi-effects processor that has the signal chain set up right to eliminate noise with the built-in gate. It appears totally unobtrusive in function.
Now I move more and more to analog effects and thus having the gate pretty late in the signal chain appears too late for killing noise effectively.

It must me mentioned that I do not have any noise from the effects themselves despite high gain, but the guitar signal itself is highly amplified and with it all the dirt the single coils pick up. This is comprised of plain simpe transformer hum but also harmonics thereof from incandescent lighting and also from computers. It is hum mixed with a higher frequent buzz.

Switching to humbuckers makes it better, but also changes tone. Turning the guitar volume down entirely of course silcences the whole chain. This proofs that the effects themselves are silent, it also proofs that the noise gate should be right after the guitar if that works at all.

I am slightly confused about where people use their gates in the signal chain, I suspect most of them try to duck secondary noise originating from their effects.
Mark Hammer once suggested double light gating, one before and one after the chain. I can always have the gate in my multi-fx processor on, too.

Does anybody know from past experience, how the Boss, MRX and ISP candidates would perform as front-end?

Thanks,

-helmut

[aquataur]

I probably should mention a few things:

* I have done all that can be done on shielding, rewiring and grounding. The pickups are not of the noisless kind, but I do not want those either.
* Moreover, the term "noise" is confusing. It is not hiss I am trying to eliminate, it is mains hum (50 Hz) and multiples thereof (100 Hz) and electrostatic coupling from neon lamps and pc appliances. I doubt if the EHX hum debugger would do any good therefore.
* I am also not  too pushed by hum during playing, even if decaying notes expose some noise. I´d rather have it quiet inbetween.
* I frequently use my guitar´s volume control to adjust the cusp of clipping.

I´d be interested to hear from you expierienced fuzzers if those pedals are fit for this job.

have fun,

-helmut

[Mark Hammer]

Therein lies the essential challenge: "noise" is not focussed in one part of the audible spectrum.

Sounds to me that a steep 50hz notch filter (or 60hz for those in other regions) at the head of the pedal chain might be called for.  Do consider, as well, the use of a dummy coil of some kind.

Now here's a project that might be orthy of development.  What if one were to have an active device that had a dummy coil mounted atop it, like an EMI sensor, and could mix that in with the gutar signal in such a way as to cancel out sensed EMI from the pickups?

Keep in mind that the basis for hum rejection at the guitar is the two cois of a humbucker acting as "dummies" for the other coil.  Systems like the Suhr backplate, and several other formats over the years (Alembic center coils, G&L under-the-pickguard dummy coils, et al) attempt to provide a passive system that can balance off the hum sensed by the pickups and the same hum sensed by the dummy coil.  But why couldn't an active circuit work too?  That might even circumvent one of the persistent problems of dummy coils: that of assuring that the sensing pickup and dummy coil detect the exact same amount of hum no matter where you face.

[aquataur]

I agree that some active system might be superior to any passive method by means of control. However, I suspect the sensor would have to be a dummy coil plus it would have to be placed at the point of origin of all noise - close to the other pickups, because distance and rotation would change a lot.

It is questionable if this method then makes for less coloration than a humbucker creates compared to single coils. At least this method of cancellation does not mutilate the envelope as noise gates are prone for.

Anyhow, I think I try the double gating as you suggested elsewhere, one before and one after the effects chain.

have fun,

-helmut

[Mark Hammer]

The "active" thing I'm pondering has the advantage that, if combined with the pickup in an active mixer, doesn't need to be placed anywhere particularly strategic.

This is the thing about traditional use of dummy coils: they are situated such that the physical location does some of the work with respect to achieving hum amplitude equivalent to what the pickup is getting.  But what if you had a pedal on the ground with an unshielded "antenna" sticking out?  It might pickup up more hum, or perhaps less, than the guitar.  Doesn't matter if there is a way to adjust the amplitude through an active mixer.

This use of omnidirectional "anti-noise" is intriguing me.  It still doesn't eliminate the need for some sort of reduction of cumulative noise across all one's pedals, but it might be a productive approach to eliminating hum at the front end without having to change pickups.

[edvard]

I too, suffer from Helmut's malady and have contemplated many ways to deal with it.
While the noise from single-coils changes with the orientation (here facing the lights, there facing the monitor, yon lies the dimmer...), an antenna-based system is going to pick up either all noise or an inordinate amount of whatever it's close to, which would almost defeat the purpose.
An instrument-mounted solution would be better, because the unit would follow the instrument in seeking noise sources.
I've long contemplated how to cobble together a dummy coil noise canceling system, but I have no idea how to go about it and I have an irrational fear of active pickup systems (which it would be, of necessity).
Are there schematics available?

As to the topic of noise-gates, I have heard from the high-gain crowd that the Boss NS-1 and NS-2 come highly recommended.

[Mark Hammer]

As to the topic of noise-gates, I have heard from the high-gain crowd that the Boss NS-1 and NS-2 come highly recommended.

Good pedals.

[aquataur]

I agree, the antenna system would pick up everything in a mix of phase and amplitude, that it will be hard to rule it out even for the best DSP´s due to its unpredictable nature, letting alone a simple analog system.

The worst enemy seems to be the computer monitor (good ole´tubes ).

Mark, I will try the dual gating system you suggested. This sounds promising.

About the NS-2 I have read mixed, but by trend better opinions than about the NS-1, which seems obsolete by today´s standard.
The ISP has good reports, but is also a multiple of the price.

have fun,

-helmut