Filter out 60 Hz hum?

Natman

Natman

New member
I have been researching midrange filters for an axe and started thinking "why not filter out 60 hz hum?"

I realized the lowest note on a guitar is about 82 Hz so 60Hz in theory could be elimintaed with a capacitor in series to filter it out.

Than I saw this video which is fairly compelling. I wouldn't do it on a cable personally but inside a single coil guitar. The drop in output would be annoying but any buffered pedal would help level it out I'm thinking...

There's nothing new here and I suspect if it really worked well we'd be using them in our single coil axes.

Has anyone here tried it? Please discuss...
 
Re: Filter out 60 Hz hum?

I don't think filtering the frequency range would be as effective as shielding/grounding. You can do a lot with shielding/grounding.
 
Re: Filter out 60 Hz hum?

Check this out. I'm convinced that designs like this are the future of hum cancelling in single coil pickups. Sonny Landreth is using the Ilitch system too.

 
Re: Filter out 60 Hz hum?

Thanks guys, those methods are both on my radar. Actually I shield all my guitars but not the coils themselves. Note that the Illitch is expensive! It's been around for years and I still haven't tried one.

I'm just wondering how helpful a simple high pass filter would work to reduce the hum from single coils (not ambient RF noise)?

Here's Rothstein's midrange filter:

http://www.guitar-mod.com/rg_mods_faq.html

With the right cap values, it could be tailored for 60 Hz and maybe narrowed with a higher value choke?
 
Re: Filter out 60 Hz hum?

Remember that even digitally, it's very difficult to drop a single frequency without rolling off adjacent frequencies. You'd need a pretty high order high pass filter to get 60Hz but not drop a significant amount of bass from your guitar.
 
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Re: Filter out 60 Hz hum?

I am thinking the filtering idea would hurt too many adjacent frequencies, and hurt the lower overtones of the guitar. I dig Music Man's 'dummy coil' system, which is active, and very quiet (as quiet as most humbuckers).
 
Re: Filter out 60 Hz hum?

It's not just the neighboring frequencies, it's all the harmonic multiples. Single coil noise is not only comprised of 60hz. It's 120hz and so on...

The Illitch system isn't transparent, the loading shifts. They try to make it inaudible on the videos but if you're playing the guitar it's noticeable. Still it's very good, that's not a judgement.

Also as a sidebar, the fact that a low E sine wave is 82hz is totally irrelevant. It doesn't mean the plucked guitar string has no content below 82hz. Even brick-walling 60hz and below has a profound effect on the overall tone. The pick attack has tons of information down there.
 
Re: Filter out 60 Hz hum?

frankfalbo said:
The Illitch system isn't transparent, the loading shifts. They try to make it inaudible on the videos but if you're playing the guitar it's noticeable. Still it's very good, that's not a judgement.
Click to expand...

Wish you'd hurry up and perfect a system like this Frank. I know John Suhr is working on it.
 
Re: Filter out 60 Hz hum?

Well, that Sonny Landreth character you just mentioned has since moved on to Fishman Fluence...so you can't say I'm not trying. LOL
 
Re: Filter out 60 Hz hum?

frankfalbo said:
It doesn't mean the plucked guitar string has no content below 82hz. Even brick-walling 60hz and below has a profound effect on the overall tone. The pick attack has tons of information down there.
Click to expand...

Good point Frank, I had not thought of that (obviously)! Guess I'll drop this idea and follow through with my DIY Ilitch coil as the most likely way to dump the majority of hum...
 
Re: Filter out 60 Hz hum?

frankfalbo said:
It's not just the neighboring frequencies, it's all the harmonic multiples. Single coil noise is not only comprised of 60hz. It's 120hz and so on...

The Illitch system isn't transparent, the loading shifts. They try to make it inaudible on the videos but if you're playing the guitar it's noticeable. Still it's very good, that's not a judgement.

Also as a sidebar, the fact that a low E sine wave is 82hz is totally irrelevant. It doesn't mean the plucked guitar string has no content below 82hz. Even brick-walling 60hz and below has a profound effect on the overall tone. The pick attack has tons of information down there.
Click to expand...

The other thing I completely forgot about is the phase effect of a brick wall filter.

Needless to say, if a simple RC filter resolved the noise issue, Leo would have done it 50 years ago.
 
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