Posts tagged tuning
I had the full intention of writing a blog on piano voicing and then suddenly realized that there are 3 completely valid meanings to piano voicing. The first meaning of voicing refers to chord voicing which denotes how you spread out the notes of a chord on the piano (quite often in the jazz idiom). The second meaning, as it refers to piano playing and pedagogy means making the melody line stand above the accompaniment. You voice the melody to be more audible than the rest of the notes you’re playing. The third definition however, refers to the technical aspect of manipulating the tone of the piano. It is this subject I’d like to delve into a little deeper.
When I was young I was slightly misguided in thinking that every piano brand had a signature sound. While there is truth in that statement, pianos can sound vastly different from model to model and can vary from even piano to piano. Why? At the core, the piano is comprised of natural products such as wood, felt, steel, leather and iron. All of these raw materials have anomalies and subsequently, no 2 pianos are the same. So while it is true that there are inherent qualities of tone related to a brand, the subtleties vary significantly from piano to piano. Voicing serves 2 purposes: one is to alter and change the global sound of a piano and two, to make a piano sound even.
What does it mean to have “even” tone? When I was 13, my piano teacher asked me to play a scale. “Play it like a string of pearls ~ matched in color and size. If you want to get louder, do so by tapering each note a little louder, then a little softer. Do everything gradually.” It was an idea that I could visualize where each pearl had its own quality and it was up to me as a performer to use some sense of skill to match one note on the piano to the neighbouring note. She taught me a lot about making simple technique musical. And when you play notes on the piano evenly in succession, it tricks our ears into thinking it’s monophonic (meaning “one sound” like the human voice).
At times, however, I’ll be playing what I believe to be consistently when all of a sudden, one note sounds different than the rest. Playing the note in isolation, it becomes apparent that this one note sounds sharper or “brassy”, bright or strident while the neighbouring notes sound warmer, mellower or darker. These are common words many people use to describe the tone of a piano. In short, the fix for the protruding note is called piano voicing. Piano voicing involves manipulating the instrument to achieve a different audible result. To create an even performance at the piano, it must be voiced so that each note sounds similar to its neighbours, making transitions in a musical line seamless. When I was in Hailun and Petrof factories last year, I took some time to watch factory workers whose jobs are solely voicing and tuning. It takes a trained ear and substantial skill to play notes quickly in succession and level the audible high spots which are strident and bring up the low notes to match the others.
So how does this process happen? How does one change the sound of a piano? To answer that, we need to think of what parts can be altered readily on a piano? Voicing predominantly involves altering the strike point of the hammer as it touches the strings. Yes, it could involve many other procedures but voicing is more commonly referred to as an immediate alteration to the wool hammers to produce a different tone. As to how this art of voicing happens, preparation precedes practice.
Pianos must first be in tune. How do you listen to the nuances of tone if the strings are not in unison? When you look inside a piano, 2/3rds of the notes have 3 strings per note. See our recent blog entitled How Often Should I Tune My Piano for a full description of the strings inside a piano. If there are 3 strings on a single note and they each are resonating at different frequencies, it’s like having 3 people talking at the same time. It’s impossible to hear the tonal quality of a note when all of the strings are not resounding in unison. So the first step leading to voicing is tuning. It is also during this time that most piano technicians make mental notes of the “worst offenders” which are anomalies across the keyboard. Because tuning takes well over an hour to get it in shape, familiarity with the piano also happens during this time. It takes time with a piano to find out what sounds it produces ~ what are its strengths and weaknesses and what areas need addressing more than others.
Levelling the playing field
Seating: At times, some notes will give off distortion. A trained technician will know that this is sometimes caused from the string not sitting flush up against termination points. Moving the string slightly can alter a note drastically.
Centering: Over time, some hammers shift from their strike position and don’t hit the all of the strings squarely. Adjusting the hammers to be striking in the center of the felt and at the same time is extremely important to consistent tone.
Travel refers to the movement of the hammer up towards the string. If the hammer is on an incorrect trajectory towards the string, it will hit the strings at more of an angle and also create odd tones or have one string strike before the other two. “Squaring” the hammers ensures they strike in the correct position at the same time.
Surface Preparation: If grooves in the hammers are significant, filing the felt of the hammers should be done to regain proper surface contact.
Action Corrections: Sometimes one note will be misbehaving mechanically and render it powerless. In such cases, it tricks our ears into thinking it has a different tone when in fact, there’s a mechanical problem. There are many issues that can arise in a piano that lead us to believe individual notes need voicing when in fact they require mechanical fixes or adjustments.
With the aforementioned areas addressed, voicing can now commence. Please note: these are piano BASICS. Pianos are much more involved but for the purpose of describing piano voicing, these are the baselines which all pianos must adhere to. These are the practical fundamentals of most household instruments and not concert level pianos which can sometimes take days to tweak.
So let me ask, what kind of tone do you wish to have coming from your piano? Beauty, after all, is in the eye of the beholder. Some wish for a power piano – strong and bright. Others want soft and felty. Personally, I look for versatility in a piano. I prefer pianos to be intimate and warm at softer dynamic levels and have a crossover where they can shift into more strident sounds when playing with force. Pianos that are icy cold or brittle at softer volumes I find somehow less satisfying and difficult to express emotionally. Conversely, playing powerful music with a dull thud also feels like it is somehow lacking.
Let’s be clear, however that piano voicing has limitations. I’ve often said that 50% of the tone of a piano is inherent to the instrument. It’s the wood ~ the soundboard, the bridges, it’s the design ~ the scale, the placement and thickness of the soundboard, the amount of ribs, backposts, rim construction etc., it’s the action ~ how it translates our musical intention into sound – all of these elements make up the piano. These I would mainly consider non-negotiable. Yes you can start down the path of reconstructing parts but this is more major surgery. The other 50% can be altered somewhat depending on the quality of the piano and the results vary drastically. Piano hammers also have a shelf life as well. Really old and “dead” sounding hammers fibers, ones that are really grooved, hardened or lifeless sounding need replacement.
Most pianos with time and playing become more brittle and harsh. The majority of the requests for voicing involve making pianos softer with fuller body. When I was young, I sought the brassy power piano. As I age, I look for tonal color more akin to “autumn leaves” ~ colourful, warm and beautiful. We get used to the piano we play and don’t consider that alterations could make the experience more enjoyable. With harsher tones, piano hammers can be “needled” in various locations to achieve those results. A needling tool simply has needles that get inserted into the piano hammer. Since piano hammers consist of felt stretched and glued around a wooden hammer molding, the insertion of the needle “fluffs” hammer felt, making it not so compacted. In other areas of the hammer head, the needle acts to give greater body or sustain. Most piano technicians know how to needle to create the desired effect.
Solutions for both hardening and softening also exist. A hardener coats the hammer and creates more brilliance in tone. Softeners penetrate and relax fibers and create softer sounds. While there are those who disagree with putting anything on the hammers, I believe that there is a place for more drastic alterations of hammers that have desirable end results. The danger is that solutions can be added to a hammer but cannot be extracted. I’ve actually played pianos rendered unplayable due to excessive chemical applications. The recourse really is only to change the hammers. But I’ve also played many pianos that have been strategically voiced with solutions for incredible results. The word here is caution and work with a piano technician you trust. Ideally, I like the felt of the hammer to speak. If you’re looking for a certain sound, sometimes changing the hammer is a better way than to try and artificially transform a piano into something it wasn’t intended to be.
Pianos are dynamic in nature. They are constantly changing. Voicing is not a do-once application but rather a process with time and maintenance. It involves keeping the piano at its best throughout its life-span. Have you lost the love of your piano? Sometimes pianos simply need to be voiced to bring it back to more of the sound when you first acquired it. You’ll be amazed at the results. Piano maintenance is so much more than tuning. Once you realize the possibilities, you’ll be amazed at how musical and beautiful your piano can be. Click HERE for a list of piano technicians in your area.
Over the last few years, I decided to run a few ultra-marathons (marathons run on trails in the forest). And I must go on record by saying that maintaining fitness is much easier than trying to get in shape to begin with. It was an arduous journey trying to get ready for my first event. But when our bodies are used to a certain routine over time, it becomes the new normal. In essence, we train in order to raise the bar for a new level of expectation.
You wouldn’t think it, but pianos can be in shape or out of shape. Pianos can go out of shape mechanically in the way that they play but can also get out of shape in the strings which determines intonation or pitch. Today I’d like to take a brief look at a bit more of a structural and mathematical concept of tuning and pitch. Before we do, we need to examine how and why pianos go out of tune and when you understand why they go out of tune, there is greater understanding with regards to getting them in shape and maintaining tuning stability.
Pictured above are the 3 types of strings on any piano. When you depress a key on the piano, it activates a hammer that strikes the strings. Depending on the zone (high or low), there are different types of strings. The largest bass notes are called mono-chords and only have one string per note. The double stringed notes are called bi-chord where the hammer strikes two notes simultaneously. And then for the top 2/3rds of the piano, a set of 3 strings (tri-chord) are struck simultaneously by one hammer. As seen on the chalkboard, there are 88 keys on the piano. When we separate the notes by type, we see that there are approximately 227 wires (which vary depending on the design of the piano). Multiply this total by the tension from each string (approximately 160lbs per string) and this gives the grand total of 36,320 pounds of string tension pulling on any piano! Note: the string tensions vary from maker to maker, model to model but also within one piano, the string tensions vary considerably. These are simply averages to grasp the concept of how much tension is pulling on the frame. Conservatively, the piano has 18 tons of tension (36,000 pounds) pulling simultaneously and that number can reach almost 30 tons of string tension for larger concert grands.
The wires then pull with an incredible force or tension. The cast iron frame (pictured in gold) together with the structural beams resist this tension. It’s a constant tug-of-war. The strings pull while the cast frame resists. Slight variations in this tension result in change of pitch and an out of tune piano. The question then is: what factors change the pitch of a piano?
There are 3 main elements which affect tuning stability:
1. New strings and windings
2. Tuning pin torque
3. Soundboard environmental changes
1. When it comes to change in tension, strings when installed at the factory will stretch. You wouldn’t think it but new strings have considerable stretch in the steel. The windings, knots and coils will also tighten and stabilize. This only applies to brand new pianos. There is a finite amount of stretch that will happen with new strings and within the first few tunings this will no longer be an issue. There is wisdom in tuning new pianos more frequently until the strings feel like they’ve settled.
2. The tuning pins are the adjustable “pegs” that technicians loosen or tighten with a tuning hammer. They are friction fit into the pinblock ~ usually a multi-laminated plank of wood. Interestingly, in England, they refer to the pinblock as the “wrest-plank”. The word “wrest” (similar to wrestling or wrench) denotes forcibly to pull or in this case, to turn the “wrest pins” (or tuning pins) inserted into the wrest-plank. Because the tuning pins are friction fit into the pinblock, they must have the correct amount of torque (the measurement of how tight fitting the pins are). Too tight and the pins becomes too difficult for a technician to adjust. Too loose and the tension of the string pulls on the pin resulting in loss of pitch. Tuning pin torque then is a significant factor that affects tuning stability.
3. Probably the greatest factor affecting pitch, however is the soundboard. The soundboard affects the tuning stability insofar as the strings cross over the bridge which is connected to the soundboard. In the picture you can see the strings cross over the bridge (adhered to the soundboard). Not only are the strings pulling end to end, but there is something called down-bearing where the strings are pushing down on this bridge. Since the soundboard is comprised of wood, it is subject to environmental conditions. Seasonally as the soundboard absorbs or dispels humidity, the soundboard will arc or flatten slightly resulting in pressure on the strings. Pianos can even go up in pitch if the arc puts considerable pressure on the strings.
All three of these factors contribute to slight deviation in pitch. When the steel strings are new, they stretch and become slack and need to be re-tuned. Tuning pins can move slightly and gradually turn out of position. The soundboard arcs more and then less depending on environmental conditions.
Making Sense of Cents
Pitch is not simply some arbitrary sound but rather, it has evolved into more concrete, measurable and universal terms. A440 is the global standard. A is the note (just above middle C) and 440 is the frequency or speed of that wave measured in Hertz (named after Heinrich Rudolf Hertz accredited for conclusively proving electro-magnetic frequency waves). When it comes to piano tuning, while you can measure Hertz, you can also define pitch in degrees called cents. As seen in the picture, each semi-tone has 100 degrees or cents. A full tone then has 200 cents. What this means is that there are 100 increments or degrees of pitch from one note to the next neighbouring note. So in discussing pitch, being a math and facts guy, I like to know how many cents the piano is out of tune. A piano that is wildly out of tune will be 40 cents flat (pianos usually go flat rather than sharp). So 40 out of 100 cents, if a semi-tone is 100 cents, that piano has fallen in pitch 40% of a semi-tone! Pianos that are tuned regularly might only go out 1-3 cents (out of a total 100). Often, pianos might go out of tune 5-15 cents in a year. What does this depend on? The 3 factors we looked at above. If your piano has gotten over “new string” settling when the piano is first purchased, then that leaves tuning pin torque and soundboard fluctuation as main factors determining pitch or intonation. The pinblock and soundboard will change with humidity. Pianos LOVE stable environments. Baseboard heaters, fireplaces, direct sunlight, drafts… even excessive fish tanks, plants all have bearing on humidity in the room which affects the soundboard which in turn affects the tuning. Change in ambient temperature (and subsequent humidity) within the house but also seasonally will make micro-changes in strings which also create difference in pitch.
Getting Your Piano in Shape
There’s a saying about piano tuning “You can’t tune a piano unless it’s in tune”. Paradoxical? It sounds that way unless you understand the sentiment. The farther out of shape your piano is, the more the tug-of-war will happen. The strings get pulled into shape, the piano tries to pull back to its known comfort zone. If a piano is 40 degrees out of pitch and you raise it to concert A440, guess what ~ your piano will not be at A440. Why? Because the tug-of-war is happening. The soundboard is adjusting to a new level of fitness. The subsequent outcome is that most pianos will pull back ~ sometimes up to 1/3 of the raise in pitch. So let’s take that example of 40 cents. One third of 40 is roughly 13. After tuning to A440 once, the piano will respond by possibly dipping down as much as 13 cents. Most technicians compensate and tune a little sharper knowing that this pull-back is going to happen. And so here’s the part that technicians CAN’T control. They can’t control the adjustment of the piano and the subsequent pull-back in 225 strings. Those strings will pull back at varying rates and thus, one tuning will never do the job getting a piano into shape that is vastly out of tune. The only way to do that is to tune again. You can really only tune a piano when it’s in tune ~ meaning that unless it’s close to pitch, you will never be able to get an exact stable tuning the first time. It is better to keep a piano consistently in tune than to let it drop significantly and try and pull it back into shape.
I’ve heard from many people over the years. “The piano doesn’t need tuning because I don’t play it that often”. While it can be true that a pianist who plays with incredible force can knock a piano out of tune, it is most likely the least contributing factor to making a piano go out of tune. Regardless of whether you touch a note on the piano or not, there is 18 tons of string tension pulling every day, 365 days per year. If a piano is prone to going out of pitch 4 cents per year, it might be out 8 cents in 2 years, 12 cents in 3 years and so forth. And pianos are funny that way. I’ve witnessed pianos that go out 12 cents in one year while others go out 2 cents in 8 years. But in closing, I will state 2 truths:
1. The farther out of shape the piano is, the harder it is to get it back into shape. And it may require more than one corrective tuning
2. Environmental stability is everything
Pianos are introverts. Hah… they like dark shady places where the sun doesn’t shine and no one rocks the environmental boat. The only problem is, we want pianos to be social and live in the center of our lives and enjoy the music with the sunshine. We need to maintain pianos if we want them to sound pure, beautiful and harmonious. I’m a firm believer in the fact that we are the recipients of the music from our pianos. If we train our ears with a consistently out of tune piano, that sound becomes the new normal. With an in tune piano, we communicate proper pitch every time we play. In closing, the message is simple: Regular maintenance is so much better for the piano than letting it drop in pitch for years at a time. Tune at least once per year and you will keep everything from sliding drastically out of alignment. Tune more than that if your ears demand it. And if you haven’t tuned for quite some time, do yourself a favour and get your piano tuned. Nothing is more satisfying than playing a piano that truly sings and really, pianos only sing when they are in tune and each note is in unison. Your piano may have gone down in pitch to such a degree that it might require more than one tune up session but as an old technician friend of mine used to tell me, “The difficult we can do. The impossible may take some time” 😀
For a name of a piano technician in your area, please visit our more than 800 technicians listed with Piano Price Point: HERE
Three weeks ago I was in a discussion with Basilios Strmec of Vienna International (North American distributers for Hailun, Petrof & Sauter) regarding the creation of virtual piano factory tours on Piano Price Point.
After a slight pause his first response was, “Glen, how flexible are you?”
“Pertaining to what exactly?” was my reply not having any clue where he was headed.
“I’m leaving for China in 10 days and if you can clear your schedule, I’d like to invite you to Hailun Piano Company to do your first tour”.
Knowing I was planning a trip to Toronto for that week I said “Let me call you within 24 hours”. I managed to shuffle some dates to make this happen as I deemed it an exciting new adventure and opportunity.
With new-to-me technology of panoramic photography I started to explain to Basilios during the shuttle from Shanghai what it is I hope to achieve. “I want to bring the masses to the factory” I said, knowing that it is an impossibility in reality but plausible with virtual technology. “I would like to give people the opportunity to look around – to see the stuff of every day life – to see the sawdust and the chisel shavings, to see the rough cast iron frames before they get sprayed beautifully in gold, silver and rose. I’d like consumers to begin with lumber and iron, leather, cloth and felt and end with a finished product ~ to show from inception to creation this process of making the piano.” OK I wasn’t quite that poetic but… you get the point.
In usual enthusiastic manner Basilios replied “Well let’s make this happen! Hailun is transparent and I’d like you to feel at home – to photograph and walk around as you would like.” It wasn’t until I started shooting panoramic images that his eyes lit up. “Wow this is fantastic! It really shows the factory as if you’re standing right here.” That was my intention precisely. The new chapter called Piano Factory Tours is in editing stage and will be released August 2015.
5 Days Later
Debriefing this whirlwind, it’s simply overwhelming the stature and size of the Hailun Piano Company. They manufacture roughly 38,000 pianos per year. Now if you do the math, that’s just over 3,150 pianos per month in 4.2 MILLION square feet of factory space. The construction of the piano is divided up into stations where each employee is trained in specific tasks. Some work on tone wood – the sound producing elements of bridges and soundboards while others work on action parts and how the piano plays. Some produce beautiful finishes and others are involved in the construction of the frames. At the end of the assembly there are usually at least 3 levels of refinement ~ rough tuning and regulation (making all the parts function evenly), then 2nd tuning and voicing (making all of the notes sound consistent) and then 3rd regulation and tuning. All pianos are inspected along the way at various levels. Oh and when you walk into the factory, the sounds – you can’t even begin to describe this one machine – up until this point I had only seen pictures – The piano gets sent into an extremely well insulated booth where this machine strikes the keys to ‘break in’ the piano. The sound of all 88 keys hitting in rapid succession settles the entire piano; the tuning of the strings settle, the hammers find their strike point and the tone begins to really blossom and not sound so ‘green’. All pianos roll through the factory on what look like train tracks. They move from one section or station to another. There are some areas in the factory with tools not dissimilar to my own wood shop having the reminiscent smell of sawdust and conversely, there are multimillion dollar polishing machines working with exacting precision to achieve that mirror gloss many refer to as “piano black finish” or ebony polish. In order to create a piano however, it’s not simply the sum of the parts – it’s the design team of piano visionaries and engineers working at computers and CNC machines (computerized cutting tools precisely notch and cut down to 1/1000th of an inch). It’s also logistics – transporting parts from one area to another and not get bottle necked at any stage along the way. Imagine if there would be a problem in one section, pianos would just start piling up at over 100 per day! So the entire process needs to flow from one section to another. And don’t forget about packaging – the creation of boxes, pallets and air tight packaging. At the helm of this giant ship is Mr. Hailun Chen – an absolute larger than life personality who despite cultural and language barriers makes everyone feel welcome. The few interactions over dinner and meetings, there were great laughs but you also recognize that he’s a remarkable leader who would be first to tell you that it takes a team to build a piano. Hah… and I thought my 5 day trip to China was a whirlwind – try building an entire line of pianos, manufacturing facilities, installing giant machinery, with hundreds of workers, an entire sales force with global presence, achieving publically traded stock status all in just 15 years. Wow.
Special thanks Mr. Hailun Chen & Basilios Strmec (Vienna Piano) and the entire staff at Hailun Piano for accommodating this photo shoot and for facilitating and sponsoring this entire trip from start to finish. Thank you so much for the tour – halfway around the world and back within 5 days. Cheers to Hailun Piano and may you see continued success and growth in the coming years.
Oh and one last thing… in between meetings, I had the opportunity to sit at a Hailun grand piano ~ model 218 (7’3” long) in a performance venue built within the factory. (You’ll be able to see it on the virtual tour). It was lovely not only to catch my breath for a moment but to also sit at this FANTASTIC piano and remember that it’s the inspiration of music that moves mankind to create and build instruments of beauty for the indulgent purpose of expressing what our hearts feel.
So you just purchased a piano. Now what? It’s kind of like bringing the baby home from the hospital; you need to give some thought as to the inclusion into your life. What about placement? Where do you put it? And how about maintenance? How much and how often does it need to be tuned? This month, we’re taking a brief look at piano follow up in your home.
I’ve quite often said that pianos are like small elephants. As a piece of furniture, they can dominate a room. First off let’s debunk the old ‘outside wall’ business where many have been told pianos cannot sit on the outer wall of a house. Back in the 1920’s, old houses didn’t have sufficient insulation and in winter, outside walls had as much ice on the inside of the wall as the outside. Fluctuations in temperature were enormous and pianos weathered much better on inside walls. This is not really applicable today. General rule of thumb, if you can touch the wall and it feels like room temperature, you most likely don’t have an issue because modern construction and insulating have effectively buffered outside extremities. There are, however things to consider as danger zones: direct sunlight, baseboard heaters and fireplaces. Direct sunlight will not only create fluctuation in temperature and humidity and affect the inner workings of the piano but it will quite often fade and damage the outer finish.
Baseboard heaters are a no-no for close proximity. They heat up and cool down constantly. Finally, being in a confined space with a fireplace or wood stove also dries out parts and the sound board of the piano. If you have an upright piano, don’t position it close to the wall and in doing so ‘cup’ the sound. General principle is to have the piano about a fist’s distance from the wall which ensures proper displacement of the sound. Do also consider acoustics of the sound as well. Hard wood floors will echo while carpet and drapes absorb sound. Plaster and glass contribute to the echo. Grand pianos sound great in corners as the tone reflected off of the lid will be heard as it reflects again in the corner.
What exactly is piano preparation? If all of the notes play and work properly, why do I need to put work into a new instrument? Let’s just say that manufacturing involves assembly and some levels of preparation. Final preparation is the last stage of adjusting a piano to its home environment. Having a piano moved half-way around the world, it has been bumped and jostled. The wood at the factory quite possibly has different humidity levels to your home and so out of the approximately 5000 intricate piano parts, some may be 90% tight but rarely are they 100%. Let me give you a small example: the hammer that strikes the string is attached to a round stick called a shank which rotates via a steel center pin on a small wooden piece called the flange. This flange is screwed into a common rail appropriately called the hammer rail. It’s my experience that if the flange screws are not completely tight, you lose transference of energy and will quite often result in audible clicks even if they are a quarter of a turn off of tight. “Well why would they become loose by simply moving the piano?” It’s not that the screws have undone, it’s that the wood has settled or cured, possibly absorbed or released humidity subsequently resulting in looser parts.
Preparation involves double checks on these screws as well as plate and action screws and the alignment of action parts. Also significant is the ‘seating’ of strings – making sure they are tight against the bridge. Bringing pianos to proper pitch for the first time is also part of that process. Finally, voicing the piano – making it sound brighter or mellower – adjusting the tone so that it is suitable in your home environment is significant.
“So… how often should I have this done?” are usually the words clients say to tuners as they’re putting on their shoes and closing their toolkits. Great question. If you’re a new piano owner, there quite often is abundant stretch in the new steel strings. You wouldn’t think so, but new piano strings will stretch for quite some time. Subsequently, tuning new pianos more frequently in the first year is always beneficial. Usually your first tuning is included with a piano purchase from a retail store. My advice? Tune another 2 times your first year and you will have a very stable instrument long-term. So what happens to strings with stretch? It’s a little like a tug-of-war. You stretch the strings and the strings pull back but not as far (often by about 1/3). You tune again, and again the piano will pull back but not as far. By the third tuning, you should have more consistent pitch. After that how often should you tune the instrument? This varies considerably from location to location and piano to piano (and person to person…lol…some people are just really picky :D) In more drastic climates, where it gets really cold and then quite warm, pianos could be tuned twice a year just following the major changes of ‘freeze’ and ‘thaw’.
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