Shoulder rest physics
I wanted to investigate how much downward pressure using a shoulder rest requires on the chinrest to "free" the left hand of its' support duties.
I don't use a shoulder rest, as it gives me a terrific pain in the neck. I now have a better idea of exactly why that may be....
And to clarify: this is NOT an anti-shoulder rest thread on my part.
It is an investigation into finding out more about how a SR functions. "You don't get something for nothing", so what are the tradeoffs? How is a SR best put to use?
The accuracy of this experiment is debatable. The torque is the product of lever length (horizontal distance from shoulder rest to chin rest) and force (weight on the chin rest). In your case, the lever length is defined by the mid point between the ends of the shoulder rest and the center of gravity of the stack of boxes (projected onto the plane of the table). From the perspective of the recording, it is not clear what the lever length is, but it seems that you stack the boxes almost straight above the SR.
The weight of your head resting on a chinrest properly tailored to your jaw shape (and considering your collarbone) should be sufficient to hold the violin in place with a shoulder rest properly fitted to your violin and to the shape of your shoulders and upper chest. The violin should be able to rest on your collar bone; if it cannot you may have to make other adjustments.
Well, counter pressure also comes from the thumb and the base of the index finger nuckle, so that's two thirds of the pressure taken care of. Also, releasing the weight of the head is enough without physical pressure. Even then, its more like the downward pressure pivots the violin against the jaw and it is the stationary nature of the jaw that gives counterpressure rather than downward muscular force.
This is kind of cool experiment, but it leaves too many pertinent factors out. For example, how much force is required on a chinrest to hold a violin up WITHOUT a shoulder rest?
Agree with Andrew. The weight of a head that's properly positioned (forward and down) is sufficient to keep the violin stationary. If you're trying to pop the scroll up with only your jaw, that's way too much pressure and it will cause neck pain for sure.
I use nowhere neat that amount of baking soda when I'm playing the violin!
I guess it’s a done deal. That’s obviously why there’s never any debate about using a shoulder rest or not...
David, without a SR, there is no fulcrum with which to support the far end using the chin rest alone.
Craig, I think you have a fundamental misunderstanding of what the shoulder rest is supposed to do. It does not, by any stretch, negate the roll of the left thumb in supporting the violin. It's function is to fill the gap between the collarbone and the jaw.
To add to Julie’s and Craig’s comments, even when using a shoulder rest the instrument should first and formost be resting upon (touching) the collar bone. Your SR it too far back, set as the primary support point while it should be closer to the C bouts to rather (this is where I differ with Julie’s comment: “
There are countless videos that clearly show that many modern teachers seem to indeed advocate for having the violin being able to be supported by the SR alone.
Roger, I have that shoulder rest positioned pretty much at the wide point of the lower bout. Could you post a picture of how you have your SR positioned?
The exact position of course depends on individual shoulders, for me it’s forward of the widest point. The body of the instrument should rest on the collarbone first and foremost. To properly fit the SR, you should hold the instrument as if you had no SR, and while holding that position, insert the shoulder rest in the gap hence created between the shoulder and the instrument. I.e. the position of the instrument with or without a SR is the same. The SR acts as a balancing point where one side is much heavier as the other. The chin is simply preventing the light side from going up. The head being immensely heavier than the other side (not to forget that it is also attached to your body, hence providing a counter force equal to the entire body’s weight), you don’t have to exerce any more pressure downward with the chin to maintain the balance. I can hardly see on your setup how a normal person’s shoulder can be falling down so steep as to be touching both the edge of instrument and the base of the SR at the same time. A 1/2cm difference in the SR position forward would likely drastically change your result.
Julie, I appreciate you input above. And I understand that there is some degree of semantics in how we want to word things in regards to such an ephemeral thing as playing the violin. But, if one is not using the SR as a means by which to actually support the violin, then of what use is filling up the space underneath the violin with a SR?
An interesting experiment, but that's not how a shoulder rest works...
Hi Douglas, ever hear the expression (from Newton's 3rd law) "for every action, there is an equal and opposite reaction"?
Craig, I'm sorry, it's not semantics or wording. What you are saying is incorrect. Regardless of whether or not you use a shoulder rest, the thumb still supports the violin, not pressure from the head.
Julie- So, the way you utilize a SR is a means to control the angle of the instrument only?
And to further muddy the waters for the sake of discussion. Many things that seem to not require any effort at all--such as browsing this thread on your smartphone, may indeed actually require quite a bit of effort and pressure that you may not be aware of. Thus, the simple act of turning and letting your head drop down on to the chin rest to counteract the support of the instrument may require more of you than you may think. Google "text neck" to find out about how simple angles of the head (without even any violins in the equaition) can add significant pressure to your spine (they estimate a 12lb head here).
Julie- So, the way you utilize a SR is a means to control the angle of the instrument only?
Since the human head weighs, on average, 10 pounds, it is more than sufficient to hold the violin by simply relaxing it into a well fitted chin / shoulder rest. Even by your baking soda standards!
“Baking soda standards”
Did my own experiment with a different approach. I rested the scroll of my violin against a kitchen scale when supported by my SR in the horizontal position. My SR is positioned approx. 47cm from the scroll / 9cm from the button. It exerced a weight of 122g on the scale (the violin is 399g) According to the law of lever, the long side x weight = short side x weight. Hence 47cm x 122g / 9cm = Chin Force. This comes to 1.4lbs minus the weight of the chin rest and instrument body weight on the short end. If I do the calculation where the OP approx. positioned his chin rest and weight, roughly 4cm on the short side, it comes to 3.7lbs (roughly the op’s finding). That is of course a very rough estimate, but validates my calculation.
Sitting on your violin will assure proper counter weight!
All kidding aside, it demonstrate the importance of properly setting up the SR. Aside from the force applied, which translate to your neck if your aren’t using your thumb to support some of the weight, raising the height of the instrument with a SR, also raises your arms, hence creating tension in the shoulders. This may be more the source of your neck pain . There is also a tendency to overly apply tension on the CR as we stress out, which is far more than required to hold the instrument.
I'm amused to read, multiple times, "there is no pressure, just weight/the jaw only blocks the motion". If one discusses physics, then you need to agree on what the words mean:
It's hard to tell how much chin pressure (sorry, "force") is "weight", and how much is muscle. I determined that the weight of my (relatively empty) head is enough, when I dozed off for a few seconds in a warm room while the conductor was trying to get the (French) choir to sing in tune.. The scroll actually rose a little, according to my alarmed desk partner.
Again, 5 points of contact. You don't support the violin with only your chin. It's not a lever. (Well, it can be a lever if you want to hurt your neck, I suppose).
Han, I measured from the center of the SR pad to the front of the CR base (a Kredle CR with a narrow 1/2 cm base). The SR is at a slight angle left to right, not perpendicular. A 1cm variance in measurement would equate to 0.2lbs difference. The furthest side (left) of the SR is about 1.5-2cm from the C Bout. Given variations of my SR position, the weight required to maintain it levelled is still less than 2lb. If I move the SR to where the OP has his SR positioned, the weight at the scroll increases from 122g to 135g. I couldn’t tell how wide his CR base was, but on my instrument the distance SR to CR in the OP’s position is 5cm. This increases the weight required to 3lbs or more if his CR base is wider than mine, which I assume it is.
Roger, could you please post a picture of your SR placement? I've never seen one placed so far forward towards the C-bouts.
Julie, when you play, can you feel where the majority of your support comes from? Left thumb? Base of first finger? Shoulder rest?
Craig, in your last photo of a player, the instrument is sandwiched between the SR and CR and does not appear to be touching the player’s body. It is IMO an example of what not to do (but I could be wrong).
Craig - to add another variable - looking at your picture above of the SR on the back back violin - when I have used a SR it has been positioned on the right as close to the "bee stingers" at the juncture of the lower bout and the C bout and on the left as close to the end button as it will hold in place. This would totally change your force calculation. But then I also hold the violin on my collarbone with the weight of my head upon the chinrest through my jaw. If my neck were longer, I would need a higher chin rest to hold it this way - and I think that would be the way to go.
William Primrose totally rejected the use of a chin rest in favour of holding up the instrument with the left hand like a country fiddle player . I you doubt the credibility of this listen to his recordings of Paganini caprices played on the viola !
Andrew, that is exactly what I do.
Craig, again, 5 points of support!!! (none of them are the shoulder rest). The support is distributed across those 5 points. If you've ever heard of the slumber party game 'light as a feather, stiff as a board,' that's a fairly good representation, although with the following caveat:
Can you please name the 5 points?
Lower jaw, collar bone, left hand index, thumb, and the bow is also seen as a point of contact (of course where it meets the strings) and therefore implicates indirectly the right arm. I dont know if Julie considers the shoulder as the 5th element. But i read that its frowned upon and could lead to physical harm.
Andrew and Roger. Are you saying you have the SR mounted at an extreme angle across the back? One end up near the c-bout, and the other back near the button? Does that cause the instrument to point way out in front of you? Or way off to the left?
Points of support (not contact) chin, collar bone, neck, left hand, and bow.
Contact and support :) but i wont quibble
OK, Julie, I’m a bit confused by that.
Craig asked: “
*remember all support isn't upward. Support is both vertical and horizontal. An example I read somewhere was if you're holding a book on your left palm and tilt it, on finger from the right hand exerting very, very little pressure can stabilize the book and keep it from sliding off your hand.
Is this the position you are talking about, Andrew and roger?
OMG, you don't use a shoulder rest as a vertical fulcrum. How many more times will I have to say this? There's no crying in baseball, and there is no vertical fulcrum (at least on the front half of your body) in violin playing. You don't hold the violin up. You hold your arm up and balance a violin on it.
Julie, I don’t use one at all. So I’m all about simply supporting using the left hand and allowing the violin to rest on the collar bone at the other end.
I am not sure how useful any data gathered in this way will be, (1) because everyone's anatomy is unique and (2) you are completely ignoring the many people who find a shoulder rest quite comfortable.
Mary Ellen, your point is quite valid.
Craig asked “
Many problems with experiment, but I'll not quibble. Many interesting comments too. SR can be comfortable, but it can take a LOT of experimentation. I find I need to adjust mine whether I'm sitting or standing. Note that most CRs have a hook like feature that keeps the scroll from falling. You drop your head to engage the hook. Okay so the force has to come from somewhere but my sense is that it is distributed among several places. But still I feel the weight of my head is doing most of the work. The thing is that the exact distribution depends on what you're playing, and I feel the SR just gives me more options ... more freedom, which is somewhat ironic because restless folks often say they experienced freedom by going restless.
"What I’m trying to dig into with this thread is to possibly find out, with empirical data..."
Julie O'Connor wrote: "OMG, you don't use a shoulder rest as a vertical fulcrum. How many more times will I have to say this?"
Perhaps because they like to rotate the instrument to facilitate playing on the G string rather than elevating the elbow?
Looks like Perlman thought it was OK.
Craig - lovely photo up there - but the left side of my SR would be even closer to the end button - as close as it could get without slipping off; If my shoulders, neck, and collarbone were different the SR positioning would be different. My arms are long and my scroll points much to the left.
"OMG, you don't use a shoulder rest as a vertical fulcrum. How many more times will I have to say this? There's no crying in baseball, and there is no vertical fulcrum (at least on the front half of your body) in violin playing. You don't hold the violin up. You hold your arm up and balance a violin on it."
I dont think this experiment reflects reality. With or without shoulder rest, the head does not or should not be exerting all that force. All the shoulder rest does is raise the violin up closer to the chin, the left hand follows and the scroll too. Its just a nearly vertical translation of the whole instrument.
Here’s a thread from previous post which I think is really well written and take into account of each one’s physiques.
Jeff wrote: “...how much force could be involved when holding the instrument this way.”
And to clarify: I don’t play with a shoulder rest (because of the reasons given in the OP). But my instructor does.
There's zero tension involved in resting your chin/cheek on the chinrest, and letting the violin rest on *both* SR and clavicule. While I admit not every SR user rests their violin there, it's a common misconception by SR haters (truly no offense intended) that with SR you cannot play that way (clavicule contact with the instrument.)
It's "amazing" the numbers of folks here who believe that the one way they learned to play the violin, or the one way they play the violin, is the only possible way to do it.
Also respectfully, I would suggest that the video could mislead susceptible beginners regarding the role of the head. This could put them in harms way (at the most) or really confuse them(at the least). It is of course your choice but I respectfully suggest that its better not to put such information unless one really has much experience and put much thought into it.
I'm still trying to figure out how it's even possible to play the violin with the left thumb tight against the hand.
Mary Ellen—that person had the thumb right up against the body of the hand with the top most segment of the thumb sort of sticking outwards. And upon the tiny “V” shaped thereby, perched the violin. She is quite a good player, but it’s not a conventional hold by any means.
Tammuz, I hear what you’re saying. However, perhaps it’s better to have a “cautionary” video out there to let people know what may be involved.
Julie, "fulcrums", vertical support etc seem to make make you angry, but your blanket dismissal of them certainly upsets me! I use them with ease and success. I don't hold my viola, I "hold it up" so that my left hand can be free to help produce some of the marvelous sounds going round in my head.
In the interest of science, I figured I best see what the deal is with using a SR with a VIOLA.
LoL :-) and that was only one CatLitter unit!
That actually is the corpse of a 17.5" viola that came to an untimely demise. The details of which are too painful to put into words...
A 17.5" viola without a SR?
No way Adrian! A 17.5" WITH a SR is what would do one in...
"impossible unless the thumb is providing some lifting action at the scroll end, or the chin is providing some lowering action at the button end"
A few observations (i.e. not just opinions..)
It's not "apalling"-I frankly pay no mind to how others play.
When using a SR, the system is classified as a "class 1 lever"
"David, without a SR, there is no fulcrum with which to support the far end using the chin rest alone."
David, I'm not sure about a couple of the points you're making, but coining the term "gravitational head force" is pretty awesome!
When my father was at Princeton, he once encountered Einstein walking between buildings. My father said, "Hello Mr. Einstein", and Einstein reportedly gave some kind of a grunt in return, might have even raised his eyes from the ground slightly.
Einstein was probably about to solve the Grand Theory or some other such monumental work of vast consequence, when your dad said “hello” and totally derailed his train of thought...
But for my Dad.... ;-)
Roger, they're the same in the classical limit! LOL
Einstein was clearly a better physicist than musician, for we violinists know that E != F flat;) Citation: Fischer 2007.
Holding the violin higher than Albert did in the photo and aiming the scroll more to the left will engage the shoulder in creating a combined type 2 and 1 LEVER approach for some people. This is what those tricky 20thC soloists like Heifetz, Stern and God knows who else who hid a cushion under their jackets to effectively raise the shoulder. Those of us who are built just so can do it without the cushion; the rest might use a SR.
My claim to fame is that my maths teacher had taught Paul Dirac many years before, and hardly let a lesson go by without mentioning it!
RE: padded tuxedos.
And to clarify: this is NOT an anti-shoulder rest thread on my part.
Adrian--can you describe what the drawbacks were for you when playing restless?
Physionomies obviously have a lot to do with the ability to
Victor, that is a very good point: the tux jacket pad does allow one to basically go either way by adjusting the shoulder slightly. I guess placing the shoulder rest up the bouts would be similar too, but i’ve found playing restless with a jacket to be more comfortable. Maybe we should all just wear sport coats when we play and both be more comfortable and class up the joint at the same time!
Right! Class up the joint. Don't forget your spats!
Roger, the setup you describe is still a type 1 level, it simply is bottomed out in much the same way a see-saw can rest with one side on the ground if say my svelte 200lbs was on one end, and my 11 year old was on the other. It wouldn't be moving downward any more because the ground (or in your example, the collar bone) is blocking it. The downward force is still being exerted on that end none the less.
Craig you are right. I suppose though if the thumb provides equal support as the chin, that we have a situation where there is both a lift and a load. That would cut by 1/2 the required chin weight to balance the instrument, more or less depending on the amount of lift provided by the thumb at various time. So 1.4lbs in my case would be the max. Load necessary to maintain level, and likely much less most of the time.
I believe the premise is wrong (no offense, Mr. First), because each player is too individual for these theoretical explanations to even apply. Also, while not "advocating" rest-less use, in truth this is what the thread is about. Why the need to "scientifically" prove that SR users cannot achieve a specific balance?
I agree 100% with Adalberto.
Adalberto, I will say this in my defense- On one level I have had a certain opinion of SRs, since they haven’t worked for me in the past, so I wanted to see why that was.
Ammm... I'm quite sure Einstein is one of those people that would never ever write down something like E = Fb. They are not the same, Einstein would cringe so hard!
You know, I saw that pic E=Fb and thought it was humorous. I never knew it was a matter of further contention....hmmm, you learn something new every day.
Craig, "Einstein" was correct, E does equal F flat for all fixed intonation instruments (i.e., keyboard instruments). But for instruments where the player can "bend" the pitch there is the importance of "context," that is, among other things, the basic key of the phrase. Also the the vibrational frequency that sounds a note "in tune" in a melodic context may be different than that which is "in tune" in harmony. "Tolerable" string quartet playing requires constant awareness of this latter problem.
Fb major? With a double flat?
That depends on where the Fb comes froman what it must blend with.
Abbb major (triple flat), four octaves, fingered tenths. Isn't that the scale that Heifetz always asked for in his master classes?
Wow that is really interesting.
I have complained about the problems created by having to use the SR as a fulcrum, and now that I am not using it as a fulcrum but more in the way Julie indicates the problems are finally evaporating. Yes, you don't want the thing to pivot, you don't want to place any more than light pressure on CR through chin. I lift my chin off the fiddle now and then when playing to ensure i don't go too nutcracker. I DO add weight with fingers pressing from my LH - especially I come down hard on fingers 3 and 4, as light as possible with 1 and 2 .
I use a Pedi SR (carbon fibre) and Kreddle CR (composite) both of which are very light.
Craig, what happened is that you tried to insert some kind of doo-dad into your post and the HTML got screwed up. You'll have to ask Laurie if you want it to get fixed.
Sylvan--you articulate very well the things I have also learned from this thread.
Craig - ypu might want to check out the book, "How Equal Temperament Ruined Harmony (and Why You Should Care)," by Ross W. Duffin, 2007.
Simon Fischer discusses tuning notes at the beginning of his _Scales_ book. If you apply this methodology to every key you will notice that many notes that are enharmonically the same on the piano would not be the same if played on the violin.
This is interesting too.