The Nature of Sustain

[Gary Dunn]

I am wondering if a PSG's sustain in increased or diminished between the choice of necks, i.e., wood vs. aluminum?

Opinions...

[Kevin Hatton]

No.

[Richard Damron]

Gary -

With all due respect to your inquisitive nature, I submit that this is a topic which has been thoroughly thrashed and trashed repeatedly on the forum.

In the coming months, Ed Packard may - as a result of his experiments - continue to shed further light on this exceedingly complicated subject. No one else has a clue - no one.

[Bent Romnes]

No one else has a clue - no one.

Richard, don't want to poke fun at your assertions, but I am in touch with a design engineer who has experience in sound. He does appear to have a clue, a good solid clue I might add. So there are plenty experts out there.

[Franklin]

The answer is YES and NO. It depends on the guitars design, the mounting of the neck and whether it is a part of the key head, or not certainly makes a difference. Metal necks sustain longer than wood necks especially when they are connected to the changer. Some will argue that happens because the wood necks are never connected to the changer as a rule. Ever see a wood tail piece?
Aluminum neck PP's sustain longer than wood neck Emmons. Same is true with the Franklin and Sho-Buds. The neck is the only difference in design with these guitars.

Paul

[Bobby Burns]

I guess the closest we have to a one-piece neck and changer, are the old Baldwin era Sho-Buds and crossovers with the wrap-around neck. These sound pretty good to me. I have not compared sustain from the Baldwin/Sho-Bud and the Emmons. I think there are more differences than just the amount of sustain. After a certain point, they all sound great, they're just different.

[Billy Carr]

I totally agree with PF. The way necks, keyheads and changers are mounted and or connected tend to play a major role in the sustain/tone aspects of pro model guitars. I've found this to be true in different guitars. I won't mention any brands name here but I've found some that were without much sustain and just couldn't compare with others. Upon checking and studying guitar construction, the things mentioned in PF's post were correct. The brands I referred are no longer being built. I believe closer tolerances with metal parts also plays a role in transferring sustain/tone. Good topic here.

[Georg Sørtun]

Well, I modified my PSG into a "one piece neck and changer" construction, with a solid aluminum neck...

...and increased sustain a lot that way. The mod also changed, increased and uniformed the PSG's inherent tone, btw.

Note that the neck on my PSG has NO sonic contact with the body at the changer-end - it is mounted left of fret 11, so it is a different construction entirely.

[Richard Damron]

Bent Romnes -

I don't dispute your assertion that there may be a few folks who do have a semblance of a clue regarding the subject at hand. The cloud hanging over the resolution of the question lies in the fact that any evidence presented thus far is empirical in nature - not supported by cold, hard scientific experiment and the published data which, naturally, follows.

With all due respect to Franklin, an aluminum neck PSG may appear to have more sustain than a wooden neck instrument - however - the lack of bona-fide experiment and published data still relegates it to the realm of empirical observation. There are too many variables to state, unequivocally and simplistically, that the mere presence of an aluminum neck guarantees longer sustain.

I would be the first to herald the arrival of solid experimental data answering the myriad "why" questions. I would urge you to prod your friend into an in-depth investigation of the subject and to publish his findings poste-haste. Sure would shed some much-needed light on the subject since we are all - for all intents and purposes - in the dark regarding this.

[Richard Damron]

Georg -

I was hoping that you'd jump in here with your intriguing mod. I know that you've explained, in a cursory fashion, how the mod works and in another thread but it would be most informative if you'd enlighten us once again.

[Franklin]

Richard,

I believe what I hear. I don't need empirical evidence to advance my hearing abilities. I always find myself attacking the strings more often when playing wood neck guitars. If you need Ed's study to conclude the difference in sustain between aluminum and wood necks, that's your journey, not mine. Hearing what sustains longer is simple to hear when I sit behind both types of construction and compare the sustain. I have two Franklins with wood necks and seven with aluminum and all of the aluminum necks sustain longer. The instruments design is the same.

Paul

[richard burton]

So that's where all the Franklins have gone

[Tony Glassman]

Richard I'm not trying to "diss" you but I think PF's opinions are anecdotal at this point. If he and his buddy can actually measure the difference in sustain scientifically, his opinion would then become empirical evidence.


empirical |emˈpirikəl|
adjective
based on, concerned with, or verifiable by observation or experience rather than theory or pure logic : they provided considerable empirical evidence to support their argument.

anecdotal |ˌanikˈdōtl|
adjective
based on personal accounts rather than facts or research

[Kevin Hatton]

My no answer was based on the neck being totally independent of both the keyhead and the changer. They are that way on the guitars I build. If they are connected then I would agree, yes.

[Georg Sørtun]

Richard,

some basics on my own site...
http://www.gunlaug.no/msc/smc-090617.html
...so I don't have to repeat myself too much

It is important to understand that the entire neck and changer is lifted off the body, and only use the original top-plate/soundboard as a secondary sound-board. The "floating neck and changer" is the main "body" that the strings vibrate against, and even the Pick-Up is mounted, cushioned, on the neck. This removes nearly all variables with regard to freak resonances and noise from the original body, so when it comes to tone and sustain I can focus mainly on that "floating neck and changer" construction.
The "neck with changer" is mounted to the soundboard at fret 11 and fret 2, with washers for distance. String vibrations excite the neck directly, and the body indirectly through the neck.

The zero-fret nut-bridge is not connected sonically to the neck - there's a very thin piece of soft rubber between it and the end of the neck. The keyhead is also not connected sonically to the neck.

I have "simply" mounted a steel guitar on top of a body that holds the mechanics, instead of the usual way of turning a body with mechanics into a steel guitar. It made most sense to me that way, and it works just fine.


Now, both for tone and sustain the secondary soundboard plays a role, but to understand that one has to know the difference between the Dekley's thin, laminated, soundboard mounted in a heavy aluminum frame, and the more normal all-wood-body PSGs.
The Dekley soundboard is easy to excite, and it vibrates strongly and audibly but dies down quite quickly. This gives a Dekley its distinctive sound.


Since the neck is connected, very firmly, to the left half of the original soundboard, string vibrations excites the original soundboard in two stages/phases.

1: the rigid aluminum neck couples the strings to the soundboard immediately, but the effect is hardly audible without putting ones ear to the soundboard. The soundboard can't really affect the PSG's tone and sustain at this stage, but adds a slight coloring that I recognize as a touch of the original "Dekley sound" - a very welcome effect since I like that sound.

2: the neck itself slowly charges and starts to vibrate in sync with the strings, and this vibration in a heavy piece of aluminum/changer with the advantage of the long "lever" from the changer down to the the mounting-points really excites the original soundboard audibly. At this delayed stage the entire body-frame starts to vibrate, but because of the charged neck the result is energetic subharmonic sympathetic vibrations throughout the body. Same effect as of an earthquake imposed on certain critical masses/buildings, but not quite so violent

These delayed sympathetic vibrations from stage 2 have enough energy to "kick back" from the body-frame to the soundboard, where they help keeping the neck/changer vibrating going in sync with the strings. Thus, they help make the string-tones bloom audibly and sustain a little longer.


The entire balance and couplings of this multi-stage construction are tuned by ear - my ear - so I can't provide mathematical formulas for it. Probably not easy to transfer such an extensive modification to just any PSG either.

Most of the sustain and tone in my PSG is in the "floating all-metal neck and changer" though, and even a more normal "non-floating all-metal neck and changer" will IMO sustain better and more uniformly than a wood-neck ... if all parts are made and mounted for tone and not just for looks.
The "all-metal neck with changer" should then be mounted firmly on the body, with metal washers to ensure just enough distance to avoid mutual dampening between neck and body. I can't say much more about "how", since I have to look at and listen to a particular PSG to decide how best to improve its sustain.

I have an old MSA S12, and another Dekley, that in time will be modified along the same lines "with all-metal neck and changer" for improved sustain and tone - in accordance with my preferences. Don't know if they need a "floating neck", but they both need to be cured for body-drop anyway since I've come to expect "no audible bodydrop" from my PSGs, and the "rigid and floating neck and changer" solves that quite nicely by distributing the forces at play on two - mainly separate - "bodies".

[Bent Romnes]

Georg,
It is interesting to read the changes you have made to your old Dekley.
In many ways, I read your descriptions as changes that you have made to suit your ear and your way of hearing things. But will those same changes also suit the multitudes? Will this tone change(which I read to be more than subtle)make the pedal steel guitar sound better to everyone's ears? Let's hope so, because if not, then a whole bunch of unnecessary work has been done; work that only suits your ears. And from what I read into our emails, and your posts on the forum, you do have a special and finicky ear for sure.

Who am I to question things? I am just one who has recently dove into this steel guitar sound issue and hardly have valid opinions. The ones I do have are based in tried and true(?) methods and the ear of many expert players, builders and engineers.

When an engineer with expertise in audio tells me that even the slightest piece of plastic will do its part to dampen and mute the vibrations we are trying to make travel thru the whole guitar and back up to the strings and PUP, then I take steps to avoid using that material, even if it is just a nylon bushing in a cross shaft. Makes sense, the engineer studied these factors which is based on research.

When an accomplished player like Paul Franklin tells me that a steel guitar is only as good as the sum of all it's parts, then I can safely assume this is a piece of learning I can take without questioning and use it to my advantage.

That is why I am putting a question mark behind some things you say, for example, that you use rubber washers in key points on your guitar. Rubber is the most deadening material we have. You also have an air gap between the neck and the body at least 2/3rds of the length of the neck. This, you say, so the neck can vibrate freely, independent of the body, sort of. By the time the vibrations hit the first fret or so, they are then free to resonate thru the body once more?

It appears that you want the body to only play a role of stiffening...in order to avoid cabinet drop, and have vibrations and resonance in the neck only. If correct, and all guitars were built that way, then we would have all same-sounding guitars. Do we want this? Not me anyway.

If this is built only for your ears, then I must say you have expended a lot of effort on something that sounds great to one person only - you.

In any event, you put forth some interesting stuff my friend. That's for sure.

[Robert Harper]

How does the sustain oo the console guitars compare to the newer models?

[Georg Sørtun]

Bent,
let's check my sound preferences, since all I've done to my PSG is to make sure it doesn't get in the way and limit my sound

a) Listened to an hour-long webcast promoting a country music radio station - containing lots of steel playing, not long ago. Most was ok but nothing special - went in both ears and disappeared, but one tune caught my attention because it sounded "just right" to my ear. Forgot the title, but it was an instrumental with Lloyd Green.

b) Sending my PSG through an NV 112 makes it sound "close enough for comfort", if I bypass the amp's equalizer section and don't add reverb. I like the "nothing but a steel, a VP and an amp" set-up, where all sound-shaping and -coloring is tied to my playing skills, and where every single success and failure is mine.

c) I use only D'Addario XL ProSteels strings - despite their tendency to break a little more often then some other brands - thanks in part to the fact that I both raise and lower my 3d string, because I've found these strings to give a more natural sound and wider response-range to minute variations in pick-attacks than all other strings I have tested.

d) My modified Dekley doesn't sound all that different from my equally old and (so far) un-modified MSA S12 "Supersustain" ( ), but the Dekley has purer tone, better string-tone separation, a wider sound-shaping and -coloring range, much better and more uniform sustain, and no body-drop

That is why I am putting a question mark behind some things you say, for example, that you use rubber washers in key points on your guitar. Rubber is the most deadening material we have. You also have an air gap between the neck and the body at least 2/3rds of the length of the neck. This, you say, so the neck can vibrate freely, independent of the body, sort of. By the time the vibrations hit the first fret or so, they are then free to resonate thru the body once more?

1: NO rubber washers anywhere - you must have misread. There's only a thin piece of soft rubber between the neck-end and the nut-roller piece, instead of just an air-gap, to prevent contact and allow for neck-expansion (even solid aluminum does expand and contract ever so slightly with temperature).

2: I use wide metal-washers on the four mounting screws for the neck, to ensure stable distance between neck and body and to distribute the high-torque tightening force over a wider area to avoid cracking the original top-plate from above or below.

3: the aluminum neck gets charged by string vibration, and because the neck is laminated of thick but uneven pieces of aluminum it acts like a low-frequency tuning-fork that doesn't have a dominant center-frequency. It has a pretty "dead" sound.
This means the neck starts vibrating sympathetic to the strings' frequencies (whatever they are), but only after a slight delay since it takes time to charge its free-hanging mass.
Once the neck starts vibrating, the free-floating and relative heavy right end with bridge/changer literally has so much leverage over the original soundboard that the sound "ripples" out from the connection points between neck and soundboard at the left end of the PSG. That's all pretty basic physics, and was one of the things I was sure of before I modified anything.

No problem hearing that the body-sound spreads from the instrument's keyhead end - where the neck is connected, and as the entire body-frame gets excited by the ripples through the soundboard and the instrument starts vibrating through to the floor, so much mass has been charged that it resonates back up towards the bridge. Resonances can of course only spread up the same way they came down, so the neck with its mass and leverage takes care of the phasing - uniforms it, and "kills" (dampen) any dissonances.
Sound-wise the instrument blooms as the tones trail, which results in re-energized strings with increased sustain and slightly fattened tones. It is in part a vibrato-effect because of the strong subharmonics.

This modified resonance chain doesn't dominate my PSG's tone, so - as mentioned above - it sounds pretty much like any other PSG apart from that the pick-attack peak is slightly weaker and the trailing tone a bit stronger then on all PSGs I have tested against. The bounce-back resonance from the body can't be made too strong, because then it would resist tone-changes and make bar-slides sound really strange.

As it is: the strings and solid, floating, neck dominate sound-wise, and the steel doesn't sound particularly "warm" or "cold" or "strange". It sounds "pretty neutral and clean" and allows me to make it sound "warm" or "cold" or "strange" at will - much more than any other PSG I have played so far. Just the way I like it, and it has very good sustain when I want that.

Just as an end-note: my modified Dekley has sounded like it does now since the early 90s, and my ears haven't told me that there's anything wrong or peculiar with its inherent tone - yet.

[Bent Romnes]

Thanks for taking your time with me.
One more thing - and maybe it is hidden in there somewhere- But why this gap between neck/body?
Ok I see that you say the sound ripples out from the neck to the sound board at the roller nut end of the neck and back thru the body. I still don't get the reason for this gap you have created. Wouldnt it be better for the neck to vibrate onto the sound board along its whole length and not just the ends?
And what about where, at some point, the neck ALMOST touches the body, I mean around the 5th or 6th fret, say, it just tickles the deck at this point, would that not make an alien sound, an irritating buzz, like an unwanted string buzz?

[Mitch Ellis]

The answer is YES and NO. It depends on the guitars design, the mounting of the neck and whether it is a part of the key head, or not certainly makes a difference.

Paul

I've never seen a steel in which the neck and the key head were made of one solid peice of metal. I always thought that they were made from two different peices of metal and placed on the steel seperatly. Did I misunderstand you when you said "..part of the key head,.."?
Thank you,
Mitch

[Georg Sørtun]

Bent,
the neck doesn't "tickle" the soundboard anywhere along its entire length, and the changer is screwed onto the neck only and doesn't touch the soundboard either.

The neck is screwed onto the soundboard with two screws near fret 2 and two screws near fret 11, and the metal washers put onto these screws create a pretty even gap between neck and soundboard along the entire length of the "neck with changer". This means vibrations are only transferred between neck and soundboard via these screws with washers, leaving the neck and soundboard to follow their own vibration-patterns independent of each other except for in/through these four mounting screws points.

These four screws - 6 mm machine screws going through the neck, soundboard and washers - are tightened extremely well. In addition to transferring vibrations between neck and soundboard they have to hold the neck perfectly in place against the entire force of the string-tension - including variation in string-tension caused by pedal/lever pushing. Not a chance for buzz there.


For completeness: one reason for the gap is the very simple fact that two large unequal pieces forced tightly together tend to disagree on resonance-frequencies and will to a large degree cancel each other out. Thus, if there were no gap neither the neck nor the soundboard would vibrate as intended, and they wouldn't cooperate and give me the even body-tone I wanted.

Having the screws with washers that holds the neck in place act as "sound-pins", creates the opposite effect, same as in an acoustic instrument, and the only thing I was unsure of when I mounted the neck first time, was if the four original screw-holes in the soundboard/neck I wanted to use were at the right places to act efficiently as "sound-pins". I found that they weren't ideally placed but "close enough for comfort", and I accepted the compromise since I also had to take the mechanical strength into account.

I can still tune the construction closer to an "ideal body-tone" if I want to by moving those screws/"sound-pins" slightly, but I'm not that obsessed with "perfection" so it can wait till I'm really bored and have nothing else to do


Note that in the neck itself I wanted to cancel out resonances in the extended E9th tone range, which is why I laminated two slightly different-sized aluminum profiles together. Result: a pretty "dead" sounding neck that resonates/vibrates at subharmonic frequencies and doesn't interfere directly with the string tones.
This pretty "dead" sounding neck, that acts as main tone-body on my steel, contributes the most to what I think is a good and uniform sustain and tone. It contributes mostly by not adding much of anything while providing the bridge/strings with a stable platform.

I am a firm believer in keeping the noise from strong body-resonances away from the strings in a steel guitar, and direct sonic coupling between the strings and all the conflicting resonances and noise in a PSG body is something I try to avoid. The "delayed and controlled body-tone" I have constructed into my modified Dekley, is one way to achieve what I want in this respect while optimizing sustain and tone in accordance with my preferences, but it is by no means the only way to do it. Plenty of room for more normal constructions to suit anyone's preferences, but when it comes to sustain an aluminum neck with a bolted-on changer tends to be better than similarly built wood-neck constructions.

[Franklin]

Deleted...... It was a double post.

Paul

[Franklin]

Mitch,

True, there are no mass produced steels with one piece keyheads and necks. That does not negate the fact that the neck contributes to the sustain when it is mounted as a part of the tail piece or keyhead or both.

In the spirit of Christmas, here's an analogy: If we put three Lego's together side by side unfastened they will serve no purpose of support to the structure they are sitting on. If you fasten them to each other by snapping those three lego parts together they will now function as one single piece. Now if we go one step farther and fasten them to the table they sit upon they will function as a single unit with the table instead of three individual units with the table.

Merry Christmas,

Paul

[Billy Carr]

Makes sense.

[Bent Romnes]

Georg, ok now it makes more sense. I was under the impression that the neck was actually touching the sound board down around the 1st fret and thereby on a slant to the soundboard and thereby barely touching it at some point. The gap you have between the two is the same all along the whole length of the neck. Finally you got through this thick skull

So you're saying thenm that more favourable vibrations are made by the neck not touching the deck except thru the anchoring points and that makes less of a deadening effect between the 2 parts