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Digital Hygrometer Introduction What is a Digital Hygrometer? Simply put - a digital hygrometer is an accurate means of measuring relative air humidity. What is Relative Air Humidity? Relative Air Humidity is the amount of water vapour being carried by the air. As human beings we are easily able to sense temperature variations- but are not that well equipped to assess our surrounding humidity levels. If we are exposed to excessively dry atmospheres for periods of time - the consequences can be severe. They include sore throats, coughing, dry skin, tiredness, itchy scalp, increased susceptibility to colds, damage to hair and increases in levels of dust and static electricity. Does temperature have anything to do with relative humidity? Yes indeed it does. Temperature is critical because it determines how much moisture the air can carry. There is a limit to how much moisture the air can hold. The colder the air - the less moisture it can carry. If you compare the amount of moisture in the air with the maximum it can hold at that temperature - then you get the relative humidity. For example - when the air is saturated and cannot hold anymore - we say this is 100% relative humidity. If you warm that air - you increase its ability to hold water and its relative humidity will drop because it has the same amount of water in it but it can now hold more. If there is a big increase in temperature then the humidity will plummet. Conversely - should the temperature drop then the humidity will increase - until you reach a maximum humidity of 100%. At this point water condenses on cold objects - or falls as precipitation. Why are stringed instruments particularly affected? Stringed instruments are particularly affected by humidity - because wood is "hygroscopic". This means that it naturally takes on and loses water to maintain a balance with the surrounding air. This causes it to expand and contract - rather like a sponge - and explains why close fitting wooden doors sometimes jam shut or can't be closed in certain weather. During winter months - the outside air has very little moisture. As this air works its way into buildings, through draughts from doors and windows - or by deliberate circulation - it warms up. If water is not added to this influx of air as it warms - it will become very dry and the humidity will drop. This is when string instruments suffer. Is it not possible to predict how the wood will respond to the changes in moisture content? No - it's not a simple matter. The microscopic, cellular structure of a tree means that the physical properties of its wood are not the same in all directions. Changes in stiffness, hardness and elasticity vary with the orientation of the grain as does the swelling or shrinkage. Weather-related changes in the size of a piece of wood are practically negligible along the grain but can be quite significant across the grain. Different pieces of wood expand and contract at different rates, depending on the species of tree the wood was cut from and the precise orientation of the grain in the sample. The shrinkage or swelling of the individual components of an instrument wouldn't be a major issue if they all changed at the same rate and moved with one another. Grain directions and materials vary and it is the disparity between the rates of change that can causes the problem. Even relatively minute dimensional changes can bring disorder. Why are double basses most affected by weather related problems? Tests show that the effect of humidity is greater on large pieces of wood. This is why cellos and especially double basses - are more prone to weather-related problems than violins and violas. So what is the ideal humidity for my instrument? Museums keep all their artefacts in a controlled environment with the humidity level set at 50% - so for your double bass we would recommend that you endeavour to keep it in a location with a humidity of between 50 - 55%. In practice this can be quite difficult to achieve as many modern buildings and concert halls are made from highly absorbent materials (e.g. dry-lined plasterboard) and are fitted with air conditioning - which significantly reduces the ambient moisture content. So what effect will low relative humidity have on my double bass? In a humidity of less than 45% - it can take as little as seven days before drying-out starts to compromise the structure of your instrument. The first signs may be some relatively minor opening of the seams. With more time the wood starts to contract and existing cracks start to re-open slightly. As the table starts to shrink it presses down harder onto the soundpost and your instrument starts to feel a little "tight". Instead of concentrating on playing music - the noticeable loss of sound and tonal quality starts to play more and more heavily on your mind. You sort of know that something is wrong but you just can't understand quite why. If I continue to ignore these initial warning signs what could happen? You start to notice that the soft, intermittent buzz, which you had dismissed as just being one of those things - has quickly developed into something incredibly annoying for both you and your desk partner. Internal studs may start to split or even be torn completely loose. You notice fresh table cracks running up from the bottom edge and now that the alarm bells have at last started to ring you check over the whole instrument and notice for the first time that the back centre-seam has come apart! A hot flush comes all over you - because you know what this means - it's a back off job and an incredibly expensive repair bill to fix. You take satisfaction from the fact that you have the instrument insured but when you get the documents out of the cupboard to read - you find hidden away in the small print - that insurance companies will not pay out for damage caused by adverse atmospheric conditions. Grrr... What would I gain - if I were to purchase and use a Digital Hygrometer? As stated in our opening paragraph - a Digital Hygrometer is an accurate means of measuring relative air humidity. Here at The Contrabass Shoppe we use them in each room in which instruments are stored and think of them as "radars for double basses". They provide an effective early warning system to detect against low relative humidity. By purchasing and making use of a Digital Hygrometer the information that you will receive from its monitor will be invaluable in helping you maintain the structural integrity of your instrument. In short - you will gain "peace of mind". Do you think that every bass player should have one of these Digital Hygrometers? Yes indeed. The Contrabass Shoppe's director - Tony Houska - comments; "All instruments have value and many of are now worth considerable amounts of money. You certainly need to protect that investment as best you can. If there is a simple way of avoiding the cost and inconvenience of taking your instrument down to your repairer - then it must be worth taking." He continues - "When you consider that at least 20-25% of all bass restoration work is due to damage caused by low relative humidity levels - I would go as far as to say that a good Digital Hygrometer is an absolutely essential piece of kit for every bass payer". How would I act on constantly low humidity readings? Obviously you should try to avoid leaving your instrument in a centrally heated or air conditioned room. If you find the level of humidity in the room is slightly below the 50% mark - then a washing-up bowl or bucket filled half full with water will help raise the level slightly. In addition you could purchase and use a Bass Humidifier. You should regard these two measures as your "first line of defence". The problem with both of them is that it is quite difficult to get the water in them to evaporate. Should your Digital Hygrometer constantly indicate sub-50% readings - then we would strongly recommend that you invest in a small cool-mist humidifier - which you should be able to purchase quite cheaply from most large department stores. OK - that all seems like sensible advice. What sort of hygrometer do you recommend? The Contrabass Shoppe Ltd - currently has one make of hygrometer available... the Hygro-Thermometer-Clock. Hygro-Thermometer-Clock The clear - easy to read "jumbo" display of this digital Hygro-Thermometer-Clock is absolutely perfect for keeping you accurately informed about the humidity and temperature levels in your bass store-room. The device features a maximum and minimum reading memory that can be reset at any time, it has an ice alert and it is simultaneously able to measure the temperature outdoors. If all that wasn't enough the device also trebles up as a 12/24 hour alarm clock with snooze function. I see that the display has three readings. What are they? The top line of the display shows the humidity - expressed as a percentage. The middle line shows indoor or outdoor temperature which can be displayed as either degrees Fahrenheit or in degrees Centigrade. The lower line shows the time in either 12 hour or 24 hour clock format. Can you go over the key features of the Hygro-Thermometer Clock please? Yes - here they are;
Can you give me a final summary please? As a bass player - every time you put your instrument down or place it in the store room after the show - those four words "is my instrument safe" automatically shoot through your brain. That's just the way it is - and always will be. We all know far too well that these large instruments are more vulnerable to structural damage from knocks, scrapes and low levels of relative humidity than any other instrument in the orchestra. In many instances those four words just keep going round and round our brain until we are happy that our instrument is safely stored. For some of us - we keep mulling over our decision even on the way home. Will my instrument still be in one piece when I get back tomorrow? Will my instrument still be in one piece when I get back tomorrow? Will my instrument still be in one piece when I get back tomorrow? Common sense usually prevails when it comes to deciding whether or not to leave ones instrument in a certain place. We consider the "risks" such as - can it get stolen or is there a possibility that the percussionist will bash into it when he moves his timpani into the store. Seldom do we bass player bother to enquire if the room is climatically controlled or if the air conditioning has been turned off - as it should. Statistically however there is a much greater chance of structural damage to our "pride and joy" from low humidity levels rather than fire, theft or accidental damage - so why do we seem prepared to take such a risk? Well it's simply because - we humans - are unable to sense or feel the amount of water vapour in the air with any accuracy. This is exactly why the Hygro-Thermometer Clock is the perfect piece of kit for home, orchestral store room or hotel room. Not only does the device provide a clear accurate reading for humidity - but it simultaneously provides a reading for temperature and time - with alarm function for those of you on tour - all in the one compact unit. Final words. You should consider the compact and stylish Hygro-Thermometer Clock as part of your "insurance-policy" for helping you maintain the structural integrity of your instrument. This really is the one accessory that no bass player should be without. Stats:
Price: UK£32-00 Shipping costs - UK, EU and USA - UK£8-00
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