Posts tagged hammers
So… it was a graph that was bothering me… i couldn’t let it go. I was looking at data from a recent piano where the hammer weight was sloped (as it should be – there are larger hammer in the lower notes of a piano and small ones in the top) and what i found to be interesting was that the frictional component was also sloped. Why would that be? But there was no more time for today…I locked the door, closed the shop for the weekend. But it was on my mind. According to the stats, i needed to reduce about 3-5 grams of friction in the lower hammers. Then i got to thinkin’… what would happen if you had a wagon that was empty versus one that was full. The coefficient of friction would remain the same – meaning that the percent or ratio of friction would be the same – but the load would actually change the ‘weight’ of friction. Thinking again about the wagon… if it was empty it would be quite easy to move right? Load it full of bricks and all of a sudden, the force required to move the wagon increased proportional to the load. So in essence, the ratio doesn’t change but the weight of friction will change with the load. Back to the piano – the hammers i measured were slightly heavy… too heavy in fact for this piano. I referenced my graph again… i was examining the weight of friction and not the coefficient of friction. After i did many checks and balances again on certain joints, i finally did the reduction of weight which you can see the article on entitled Hammer Shaping. What gave me a tickle though was the fact that with the load reduced, so also the friction reduced by the exact amount i needed – a few grams.
PS… don’t know whether the coefficient of friction changes when the friction becomes the kids fighting… <sigh> i remember those days all too well
When you ask a child to draw a picture of a car, invariably it looks like this – wheels (with spokes hahaa), windows (again with panes lol) and exhaust. Much is the same when we think of pianos – black and white keys as well as strings and hammers. Everything in between magically gets glossed over. But it’s in the attention to such details that make a piano go from just ho-hum to exceptional. There are times that you sit at a piano and it REALLY responds. That piano makes you not only sound good but it also makes you want to play MORE! That’s because someone somewhere in the world has connected the dots from keyboard to string. More accurately, that’s the evolution of many hands spanning 200 years or more with the inception of keyboard instruments. It’s naive to say that one person designed the car as we know it today… so too many people have been involved over the years with the development of the piano.
But there are four basic elements from which we derive “good” touch at the piano. They all must be in check for a piano to function. And they are:
The down weight refers to the pressure required to press down a key on a piano. The up weight is the weight needed to bring the piano key back to resting position. Friction is the perceived weight on all the joint and moving parts while the action ratio is the lever system (called whippen assembly) that multiplies the speed, weight and force of the hammer from the key.
So… in my curious nature, i start asking questions. Why do we need friction? It’s not that we NEED friction but too little of it, and parts are usually too loose and will start producing noise. Too much of it (as on the Chickering grand i just worked on) and the touch feels too heavy. Concert instruments should range between 50 and 55 grams of touch with friction representing 10-15 grams of that touch weight. With too much friction, the piano i just worked on clocked in at just over 80 grams of touch – completely unreasonable for normal playing. Question 2 – well… why not just counterbalance the touch using weights in the keys? If you’ll notice on the sides of your piano keys there are small circular weights made out of lead. Well the lead weights will have some effect for the initial movement of the hammer but in dynamic playing those lead weights will not compensate for rotational inertia at all. Nor will they do any good for either friction or up weight. So why not then just have really light parts and light friction? Good idea but… the speed of the key is also determined by the return… the return requires weight.
The balance then is this – 2 elements of the four are relatively easy to control while 2 are not. The action ratio – the intrinsic design of the piano – not so easy. That’s like saying “Can we just change the pistons on this engine?” Not easily. The second part is the up weight. The up weight carries direct correlation to the hammer weight alone. The other two factors – friction and down weight can be readily altered. Friction is by far the biggest culprit that i’ve seen. And down weight can be counterbalanced with the aforementioned weights. Once the balance is achieved however, the piano becomes a wonderful and inspiring instrument. Below are two pics of lead weighting this last week – some tools of the trade and different lead weights across the keyboard ready to be installed.
There are SO many differences in piano design. “Well aren’t all pianos kinda the same?” you ask. Not at ALL!!!! (I can’t emphatically add more stress to this point). Yes pianos operate the same – they all have soundboards, strings, keys and actions. Think about cars… BMW, Toyota, Honda, GM… they all drive but do they feel identical? Of course not. Even within the same company there are huge differences between models. Toyota makes (my beloved) Landcruiser but they also have made the Tercel (and trust me… i’ve owned both and there are few similarities). Pianos, within the same company have different designs. These designs are called “scales”. When you play hundreds of pianos you will appreciate a good scale. So what’s the difference between a good scale and a bad one? Oooohhhh (rubbing hands together) where do we start? Hmmmm let’s start at strings: There are 2 types of strings on any piano – plain wire steel treble strings and copper wound bass strings. In the steel wire treble strings, there are about 2 dozen sizes of wire (plus half sizes!) ranging from 0.029″ to about 0.059″ in thickness. To look at them, they all kinda look the same but they are INCREDIBLY different. So each note is matched in length and tightness to the pitch of the note. Someone then decides “OK let’s use size 14.5 wire for that note on the piano”. Now that’s part of the design – part of a decision to make a piano sound a certain way. Now getting into the bass section… OMG! There are hundreds if not thousands of permutations on what could be used for the centre ‘core’ of the string but also the copper winding… how much mass, how long is the copper blah blah blah… there are HUGE choices to be made on JUST the strings alone. Which reminds me… i should write a blog about great sounding bass strings… cuz trust me, not all strings are equal (far from it). And believe it or not, there are different grades of steel wire as well – all factors that play into the overall sound of the instrument. So that’s just one tiny tiny element of piano design… then you think about hammers – the quality, the weight, the placement… the action – the various types…. the frame, the soundboard, the quality of the wood… even the expertise of installation… the list goes on and on and on!!! Someone once told me “The piano requires the attention to a thousand details”. I believed him… THAT’s scale design.
All this to say… i have found that there are 2 pianos that i tune that i REALLY REALLY enjoy. One being the Yamaha C7 – it’s the 7 foot Yamaha grand. The other is a Boston 6′ grand (designed by Steinway, manufactured by Kawai). Both have SUCH smooth scales… meaning that the sound from one note to the next is like a string of pearls – matched in tone and timbre – fundamental and overtones. Nothing beats a good scale. Shout out to Steve in Metchosin who has me regularly tune his C7 and to Hillary and Lawrence on their choice of such a wonderful Boston. Thanks… those pianos remind me of why i love to play.
Recently i was hired to work on a Broadwood grand. Now for those of you who don’t know, Broadwood has an illustrious place in the world of piano making. Established (get this) in 1728 (yes you read correctly), this company made pianos for royalty (obtaining the Royal Warrant for manufacturing – see lower left photo) and had probably the most famous historical endorser Beethoven himself. Upon gifting a grand piano from Broadwood, Beethoven wrote a thankyou letter back in February 1818: ” I shall regard it was an altar upon which I will place the choicest offerings of my mind to the Divine Apollo”. Think about the fact that this company was established 125 YEARS before Steinway. Now obviously in the early days they were manufacturing clavichords, harpsichords and square grand pianos. The Broadwood company became known for their actions (internal mechanisms) and also is credited with the sustain pedal.
The piano i had the opportunity to work on was a “barless” grand meaning that it had no reinforcement bars or ‘struts’ to hold the tension of the almost 18 tonnes of string tension. Instead, Broadwood made a full perimeter frame which appears to be almost double in thickness – making this an extremely heavy instrument. (see photo of strings) The major problem with the piano i worked on was that it had a cracked action rail. If you’ve ever seen the inside of a grand piano, you’ll know that all of the hammers are screwed in place to one long rail called the action rail. If the action rail is cracked, many things happen – first, you don’t have a solid base to attach the hammers. That creates ‘travel’ where the hammers will jostle about not hitting squarely the strings. Second, believe it or not, if a screw is so much as even loose on an action rail, you’ll hear the subsequent ‘click’ of the hammer. So there were a number of hammers clicking before i attended to it. And finally, the regulation. Regulation is the process of fine adjustments to streamline the flow from key to hammer. It’s what makes a piano feel ‘right’ or positive. With a cracked action rail, the hammers wouldn’t stay in alignment. After quoting on this job, it then struck me… “what have i got myself into?” Action rails have nearly 200 screw holes, thickness requirements down to the thousandths and fore and aft placements that need tending to. Well i’m always up for a challenge. And so before ripping this piano apart, i went back to the calculations. There’s a joint near the hammer called the flange. And for those who are interested, mathematically, you should be able to compute flange height. Simply, the string height inside the body of the piano minus the length of bore (LOB) – which is the centre of the shank to the tip of the hammer SHOULD equal the bird’s eye. The what? The bird’s eye is the nickname given to the joint of the flange. See? It looks like an eye… kinda… ok maybe not… but it’s a steel pin surrounded by cloth inserted into wood. So after calculating the bird’s eye, i managed to then thickness sand the new rail just under 3 thousandths of an inch (about the thickness of a piece of paper). So once everything was installed? The moment i had been waiting for… it WORKED! but it just needed a lot of adjustments refitting the old parts. It was a fun experience and more than that, exciting to bring a tired Broadwood (the silk purse) back to life.
Ever wonder what makes one piano sound bright and strident while another more mellow and warm? Well my son plays the drums (and piano of course!) and i find it interesting that it’s the attack point that determines frequencies. So… let’s say for example a drummer pulls out a pair of brushes to do a jazz number. Next song he uses sticks for a rock song. Finally, let’s think of soft mallets. Now think about the fact that the drums themselves didn’t change. The rims, the skins – all remained the same. What changed however was the attack point – more specifically the density of the surface. So the brushes have many fibers put together. They ‘swish’ the drums more than hit in part too because the fibres are flexible. The sticks have a very defined strike point but also a firmness to them. The mallets on the other hand are ‘felty’. Each of these accentuate – now this is key – different frequencies that already exist within the drum. The harder the strike point, the more the drum will accelerate the frequencies akin to the mallet. Now in pianos, the hammers are the mallets are they not? They strike the strings – they present the tone. It is at that strike point the tone is established. So if you want different sound, simply change the hammers then right? Well…. sort of. 50% of your tone will be in that strike point and 50% will be the frequencies accelerated within the piano itself. Back to the drum analogy – the mallet can change and produce varying degrees of brilliance but the drum still embodies all of the frequencies… whether you enjoy them or not. So are you stuck with the tone that’s in your piano? No. In the words of the Germans “Vee haf vays unt makink dem talk!” – There are methods to alter the sound – by manipulating the strike point – to change the perceived tone. That’s called voicing.
When i was younger there were these books called “Where’s Waldo?” They consisted of busy cartoons where you had to find this one character named Waldo. I don’t know if you’ve ever seen those puzzles where they’ve changed 10 things in two different pictures and you have to find the differences but today’s post is something similar to that…. let me explain.
Last week 2 pianos came into my store – a C3 and a G3. For those who don’t know, both of these are famous Yamaha models of the same size – 6’1″ grand pianos. Both are spectacular. They made both of these models overlapping the manufacturing dates for almost 25 years! What is rare for me though is to have 2 within a few years of each other (namely 2) and to note the differences. I had preconceived ideas as to what those were but i was sadly mistaken. They are without question different designs (or in the piano world ‘scales’) but what are the detailed differences?
I took a few measurements and i must admit they’re very similar in many respects. First thing i did was a measurement of the gram weight of the hammers. Exactly the same although they ARE stamped differently – is their density slightly different? I then measured the keys for balance point – the same. I was told that G’s didn’t have duplexing but both of these were exactly the same. Crossover was the same. I also measured the bridges and they were slightly different but not hugely (a 5mm difference). The only 2 areas of change that are notable: one is a cosmetic difference – a beveled lid on the C whereas the G is plain. Second and by far the biggest difference – the rim on the C is wider in the tail. What this means is that there are more square inches of soundboard – giving more vibration/volume. Interesting.
Playing the two pianos – if you didn’t have a point of comparison it would be next to impossible to tell. The major difference though from the player’s point of view is that the C ‘breathes’ a bit more. It feels somehow fuller and the sound seems a touch more ‘distant’. The G feels ‘close’. The tone appears to be right in front of you.
So there you have a brief and short comparison. Yes, you could pull apart every joint, every angle, every string gauge but the long and the short of the matter is that they’re both wonderful playing and sounding instruments and the changes are negligible.
When it comes to pianos… size matters! Bigger is ALWAYS better. In pianos there are four areas where size comes into play: the soundboard, the hammers and shanks, the strings and the keystick. All of these four areas contribute to a piano sounding as rich as possible and feeling as consistent as they can be. The soundboard is the amplifier to the piano. The more square inches of soundboard, the greater the resonating area (if it’s manufactured correctly). The longer the stings on a piano (which means either length in a grand or height in an upright), the deeper the voice of the piano. The longer the shank (within reason), the better the blow distance of the hammer to the string (and also less of an arc is required). And finally, the longer the keystick, the greater the control. That is why taller uprights are considered ‘professional’ and semi-concert grands and concert grands are 7 and 9 feet long… Bigger is ALWAYS better.
Pictured are two pianos – the one above is a small upright piano. The one below is a tall professional instrument. Note that the size of the ‘action’ – the mechanism is considerably taller in one than the other. This provides better control over the keys – especially in the area of quiet playing.
Quite a number of years ago a friend of mine watched a show on TV about beauty. What was interesting to note was that they took a number of pictures (i hate to say it…sorry i’m not sexist but…) pictures of women of all different shapes, colours, kinds and sizes and showed them to different cultures asking “Point out the most beautiful”. The statistics were interesting… that regardless of culture there is a general sense of ‘beauty’. And before you get your nickers in a knot, let me just say that in North America, they’ve manipulated that concept to the NINES! to the point of disgusting. It’s created a weird box that women are somehow supposed to fit into – regardless of the fact that most do NOT.
I was tuning a piano this morning – thinking of the concept of beauty in tone; how 8 out of 10 of my customers listen for a similar type of tone. I was contemplating what the ‘averages’ were in piano sound – that if you were to play a number of pianos, what most people would find pleasing. Ok follow the rabbit trail here… i was then thinking about connecting a spectrograph (an electronic device that displays a breakdown of frequencies) to pianos that are considered ‘beautiful’ and analysing the correlations of tone. (i know, i know…piano tuning is boring…lol… i have such thoughts when i’m tuning for better part of 2 hours…lol). So after the tone is ‘visible’, then look at the physical makeup of the piano – the felt, the strings, the make and model etc and try and reverse engineer the formula. Why? Well, there’s this thing called VOICING. Voicing is the art of manipulating the piano hammers in such a way as to enhance frequencies or remove unwanted frequencies. When i was young, i thot that each piano company had a certain tone. Yamaha had a tone, Baldwin had a tone, Kawai had a tone, Steinway had a tone… etc… and to a degree, that concept is true. But what MANY people don’t know is that the tone can be altered almost up to 50%. What that means is that you can have an extremely mellow sounding Yamaha – which typically is a brassy bright instrument. Through voicing, you can change the way the fibres of the hammer strike the string. Once this is accomplished, pianos can go from very mediocre to dazzling!
Well… my time is up. I’ll write another blog about voicing some time…promise. And there you’ll understand the basics how-to’s of the process of voicing.