Strange string overtones, sitar like, on PSG

Helmut Gragger · From: Austria

(This has nothing to do with electronics, or effects. At best, unwanted side effects...)

I notice some really annoying ringing overtones on my PSG. I worked together with the maker of the PSG, we are both clueless. Maybe one of you folks has had this before;
the soundclip is here: http://me.aquataur.guru/musicstuff/soundfiles-steel/test_sitar_effekt2.mp3

When plucked, the string really begins to bloom.
This is very annoying during playing, because it is piercing, really poking out.

those were the conditions for the recording:
(the first two tones on a lower string sound ok to me..)

* does not change with the picking position
* I use a dunlop #920 bar (220g)
* I pluck with medium attack
* it is not related to picking angle.
* it is not related to the material of the picks, or if I use thumb/fingers. works with bare fingers too.
* I press medium, damp correctly behind the bar
* it is not the string quality. Used SIT and Pyramid.
* changer heads look like new.
* strings are a few weeks old, 10 playing hours. Was the same when new.
* predominantly on string #2 and #4, but others as well.
* heared it slightly on wound strings too.
* played with pickup height, no change.
* played unplugged, audible too.
* happens everywhere, but seemingly more noticeable up further.
* audio recording on fret 10.
* there is nothing apparently loose or in resonance underneath.

Thanks for your help folks.
-Helmut
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Steven Paris · From: Los Angeles

Put an oscilloscope on it to see the waveform. Sounds like clipping to me.
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richard burton · From: Britain

I've encountered this phenomenon in the past, it was so annoying that I resorted to putting a tiny drop of thick oil on the top of the changer, to kill the decay of the note.

I have only ever noticed it on modern steels, vintage steels don't seem to have the problem.

I have also noticed that the 'meowing' decay that I find so annoying, is considered to be 'The Sound' that a lot of pedal steel players search a lifetime for Shocked

This 'meeeooooeewing' decay seems to be an inbuilt feature of modern steels, impossible to eradicate.

Mike Ritchie · From: Florida, USA

Make sure your tuners are securely attached to the key head, I had a loose one that caused that same problem. Tightened the nut, problem solved.

Donny Hinson · From: Glen Burnie, Md. U.S.A.

Are you using a compressor?

Helmut Gragger · From: Austria

I see what you mean by "meowing". This describes it well.
The keys are all firm.
I would not have thought that it was on the head side, since I am barring further up the neck.
But it does indeed also appear on open strings.

I am running through an fx device, but it is the same if I run direct. I donÂ´t think it is clipping, since I have an external volume pot after the guit. It does it even dimed.

No I donÂ´t use a compressor. As I said, it always does it.
This is the two good tones in the front of the audio file.

This is the meow. There is something inbetween the peaks. I donÂ´t know how to interpret this.

You think vintage steel vs modern makes a difference? Hmm. I can only imagine the material of the heads, which is sometimes stainless steel today, but mine are aluminium, which is the same as vintage.
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Ryan Lunenfeld · From: Colorado, USA

it sounds like you're hitting the natural frequency of one of the components and it's causing resonation.

I personally like that sound Confused

Donny Hinson · From: Glen Burnie, Md. U.S.A.

Helmut Gragger · From: Austria

This max explain why thinner strings exhibit more of that â€žringâ€œ, since heavier strings donâ€˜t flex that easy and are a bit away from their pivoting point before any excursion appears.
A steeper radius decay will help.
But this means Iâ€˜m stuck.
Hmm. What about this oil trick?
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Georg Sørtun · From: Mandal, Agder, Norway

That "ring" is what "the Edge" on some Jackson models are meant to solve. Adds slight offset when pedaling at higher bands, but should not be much of a problem.

Helmut Gragger · From: Austria

Never heared of that. Looked it up, it appears to be some b-bender for electric guitar. I donâ€˜t see the connection, could you elaborate on that?
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Georg Sørtun · From: Mandal, Agder, Norway

Looks like they have dropped the original "Edge", which was a drop-off on the changer to create a narrower bridge-point and thereby prevent "zing" tendencies. The negative was that the bridge-point then of course moved with raises.

Helmut Gragger · From: Austria

Ah I understand.

Actually, I had the suspicion that the big radius of the changer is providing such a gradual roll-off that the string does not have a small enough and well defined fulcrum point, like on a standard guitar bridge.

A small portion of the string clings against the changer close to the fulcrum.

This would explain why thin strings exhibit the phenomenon more. Thicker strings are to stiff to start flexing immediately at their fulcrum point. This is well known on bass guitars and is the reason for some intonation problems btw.

I had the idea of putting something under the fulcrum point, obviously Jackson had this too. However it is clear that the fulcrum point is moving, so it would only work statically, or in one direction maximally, but not in both.

Do you have any pictures of that, would be interesting to see how they went about. Looks like the phenomenon is well known.

I found a picture of one of their steels and enlarged the changer section. You clearly see a cut-out there for the very reason explained above.

Note they left #3 out, which is notorious for breaking.

I looked at my steel with an enlargement glass and a good light source, you wonÂ´t see it.

I looked up other steel pictures, Jackson are the only one who seem to take provision for this. None of the old steels have.

And I cannot remember such problems on the two steels I had before (MSA and Sho-Bud).

Excel actually did it right:

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Georg Sørtun · From: Mandal, Agder, Norway

No pictures I'm afraid. They have removed all about it, and given the "Edge" name to something else.

The bridge-point for 3d string moves almost 3mm for the G# to A raise, which is too much for a narrow and moving bridge-point on the regular roller/finger to go unnoticed on higher frets.

It is however the reason I intentionally only sand off a very tiny fraction "inwards" of the surface on those rollers if/when I notice a "zing" in thinner strings on my oldest PSG (40 year old Dekley), creating an invisible roll-off while leaving the actual bridge-point alone. Has not caused intonation issues yet after 5-6 such fixes.

Helmut Gragger · From: Austria

I was thinking about this but I looked if there was a less invasive method.

But what you say proves that the problem exists on older guitars too, which is reassuring for my theory.

Funny that it is not displeasing on all guitars. Maybe the pickup or what.

Can you describe in words how the Jackson contraption looked like? Something rigid and slim that had the curvature of the changer head? Or just a piece of flexible stainless steel tucked under so that it ended in the right spot?
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Georg Sørtun · From: Mandal, Agder, Norway

A cut-out in the roller a mm or so off the bridge-point, rounded off to create a narrow bridge. Your picture shows one way to do it, only difference being that the cut-out was full widt of the roller and on all strings.

I would not dream of recreating it on a new PSG, as it will not work well intonationwise.

Tucker Jackson · From: Portland, Oregon, USA

Wait... isn't this just a normal case of the string eventually wearing a groove in the top of the changer finger? It's happened to every guitar I've owned. You know it's time to fix it when the 4th string starts to sizzle or 'zing' and sound like sitar.

About once a year or so, I lightly sand the grooves out making sure to do it in a way that maintains the curvature of the finger (sanding a flat spot on top will make the problem worse!!). Note: this works on the typical aluminum fingers found on most guitars. Do not sand if your guitar has hardened chrome fingers!

I use 400-grit wet sandpaper to get the groove out, and then use a polish like Simichrome to do the final smoothing. Be careful to keep metal filings and simichrome out of the crack between the fingers, just focus on the top. It's a delicate operation.

There are several threads on the Forum about this. Ricky Davis uses a scouring pad instead of wet sandpaper, the kind you use to wash dishes. And Georg SÃ¸rtun uses paper and toothpaste:
https://bb.steelguitarforum.com/viewtopic.php?t=301051
.

Lee Baucum · From: McAllen, Texas (Extreme South) The Final Frontier

Yes. Sounds like the dreaded "string zing" that has been discussed here on the Forum in the past.

Helmut Gragger · From: Austria

As I said initially, the changer head looks like new and it does appear on all plain strings from 1-5 in various degrees.

Ah, "string zing", now we are coming closer. Sometimes it is just about knowing the right buzz words...
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Donny Hinson · From: Glen Burnie, Md. U.S.A.

Push the string slightly off it's normal position (to a smooth part of the finger crown), and see if it makes a difference. Winking

Helmut Gragger · From: Austria

After more scrutinization I landed with the following conclusion:

What I called "sitar effect" is more aptly called "string zing", a subject that has been attended to here abouts galore.

According to the suggestions in earlier threads, I have tried to... with no improvement

* dampen behind the changer with stiff foam
* provisional foam damping between the damping (bar) hand and the roller nut (the influence from the roller can thus be excluded for a "fretted" tone further up)
* foam damping behind the roller nut
* different strings
* oiling here and there - eek
* move the string around the changer, which looks perfect anyways
* "operation paperclip" on string #4 (the worst), i.e. a piece of paper under the string at the changer side. This very clearly creates a tiny, but well defined sharp pivot point. With proper light, you clearly see the gap. If a deformation of the changer curvature were the problem, this would have solved it.

I thus come to think that the changer is much less of a problem for the zing than we concluded. Doing things to the changer and / or changing strings may have eliminated the problem for some, but I have the suspicion that the real reason had been a different one that has not yet been recognized and was addressed inadvertently, leading to a wrong conclusion.

One thing that dawned on me during this damping rigmarole....
We all ranted about the changer curvature and the apex where the string leaves the changer and so on.
Maybe we were all barking up the wrong tree. What if the problem were at the bar side?

It has about the same radius as the changer! I quickly got hold of a flat head screwdriver (anything with a well defined slim edge would work) and was holding that to the string perpendicularly. This would create a situation similarly to a fret on a standard guitar.

Actually this problem arouse much earlier on my lap steels, when I noticed that on bar slants very low down (which can span quite a distance) the bar gets so much slanted that the angle of the bar at the apex gets flatter proportional to the slant angle (ultimatively approaching zero), which created some real sitaring effects.

Note that for the experiment you may need some dampening under the left side of your left hand, to deaden that part of the strings, since your left hand may be occupied by holding the screwdriver.

That said, I hear much less of zing!
Could somebody try to verify this impression experimentally so as to exclude imagination and wishful thinking?

That speaks for the bar to be the source of the problem. I donÂ´t have this on the lap steels, but then the string gauges are smaller there and the tension too.

If that were the cause of the zing, we are forked. Sad

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Georg Sørtun · From: Mandal, Agder, Norway

I am sure many have performed various tests to pin-point the source of string zing over the years. Most seem to have landed on wear on the bridge/changer as cause, but if one wants to that "zing" sound can be provoked at any end of the vibrating strings.

Apart from making sure the bridge/changer curvature is as perfect as it can be, I have not found mechanical issues that need correcting. As with most "noises" that can be made on PSGs, I see the "zing" as an effect to play on by manipulating the bar, pick-attacks and dampening – not something I want to permanently eliminate.

Donny Hinson · From: Glen Burnie, Md. U.S.A.

Tucker Jackson · From: Portland, Oregon, USA

Hmm... I would buy into the bar being the problem if all of us who use a standard-sized 7/8" bar had string zing all the time.

The bar may contribute, but I've continually fixed zing by redressing the changer finger and putting on a new string.

Also, the test of moving the sting out of the groove is a great one -- but if it still zings, it's not definitive proof that the problem is elsewhere. It's possible a prior owner has already corrupted the curvature of the entire finger with sloppy sanding. So, even when the string is out of the groove, it still zings. The remedy is to sand the finger back into proper curvature, concentrating on the side nearest the fretboard to counteract the too-flat area on the top.

Paul Seager · From: Augsburg, Germany

I get this problem on a couple of old European lap steels. It is usually the "wear" in the groove on either the nut or the bridge - it depends on the instrument's design.

The following has helped:
If it's the nut end then rub the groove with a graphite pencil. If that doesn't help then a small, thin piece of paper may be enough to fill the groove.
If it's the bridge I use paper. If that doesn't work I wrap the string with sticky tape (eg. Tesa) where it runs over the bridge. But only a very small amount because it will change the resonance of the string very noticeably.

\paul

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