Mounting Marimba Bars (Discussions with Alan)
-----Original Message----- From: Alan Sent: 15 May 2009 To: firstname.lastname@example.org Subject: Mounting Marimba BarsHi Jim, every time I make a new instrument and drill my holes at the nodal point, I can't help wondering why horizontal holes and therefore fixing is preferred over vertical holes & fixing. Is it playing surface and ascetics? Thanks, Alan While I have your attention, what's your opinion on evenly graduated bars (same dimensions varying length)versus graduated bars? (varied bar size)Not so much from a playing perspective, than superior sound. Does the material used to make resonators, (PVC over Aluminum) have any effect on the timbre of the sound produced?
Finally, ever tried Velcro as a bar fix? works well for tuning and temporary fix.
P.S. Re, Brads e-mail 24/8/2004, I have the same problems only with the G not F, I just make another note, this is the nature of wood. Thanks again, Alan
Hi Alan - thanks for your email.
Ok - I'll go questions one at a time..
1. - both vertical and horizontal holes are often used. Traditionally vertical holes are used for the diatonic "Orff" style instruments where the technical and musical requirements are not that critical. The horizontal method is generally superior but for the Orff instruments this is not as important as the ONE benefit of vertical holes. This is that you can remove the bars individually. This is critical for diatonic instruments as if you want to play in a key other than C Maj you need to substitute one or more bars for "black notes". For example if you wanted to play a tune in F Maj you need to remove the "B" bars and replace them with "B flat" bars. For Pro instruments which are chromatic this is not a concern so horizontal holes are used. Some advantages are: Sets of bars are strung together so none get lost and the order is never mixed up. (as you said) There is no peg sticking up above the playing surface which looks not so good and can damage a mallet if there's accidental contact, not to mention bend the peg. With vertical holes, the bars can very easily bounce off their pegs - particularly when played on the end of the bar which is common in modern marimba technique. This tends not to happen so much with horizontal holes. Most importantly... the suspension is more forgiving. Firstly because the bar does not make any physical contact with a fixed surface. You see in addition to the string acting as a soft buffer like the rubber that the bar would sit on in a vertical hole system - the string itself is free so move a little. This not only gives more movement, but secondly it allows for the suspension point to be slightly away from the actual node of the bar without much effect on the vibration. This is important on bigger range instruments where the horizontal struts are positioned along an "average nodal line" which because of that inconsistent nature of wood you mentioned, does not always line up perfectly with the actual nodes on every bar. Also worth a mention - many glockenspiels - even pro ones - use vertical holes. Mostly because the bars are usually too thin to accurately drill horizontal holes easily. Also the sustain and nodal position accuracy is never a problem with steel bars.
2. - Even vs graduated bar widths. Well on a xylophone or glock where the notes are all high I would prefer even bar widths. Most commercial instruments are this way as it makes playing easier. In these higher range it is not sonically a problem although you may notice the lowest notes on a 4 octave xylophone start to sound very "bright" - more harmonic to fundamental ratio. This is part of the characteristic sound of a xylophone anyway so it's not generally considered a problem. On lower pitch keyboards like vibraphone and particularly marimba where the range can be very low - then ALWAYS graduated bars make more sense. It is almost impossible these days to find a commercial instrument without graduated bars and for good reason. In fact over the last 20 years the trend is for increasingly wider bars at the low end. People are starting to realize the inadequate nature of narrow bars at the low end. Put simply - human hearing drops off exponentially as the frequency goes down and we need to compensate for that by pumping out more energy at lower notes. If we do not, our perception is that of an uneven instrument and a weak bottom end. Marimba players often crack low bars - partially because they are so thin and easy to crack, but also because they are overplaying them in an effort to keep up with the volume from the middle range. On most instruments this is not really a problem so much because each note has a series of harmonics it produces which we hear as well as the fundamental. Even though we may not hear he fundamental strongly - or even at all! - our perception is that we do because the brain recreates the fundamental from the relationship of the upper harmonics which it hears easily. This is of course a subconscious process. With a percussion keyboard the upper harmonics do not follow the harmonic series so this does not happen. This means that in order for us to perceive a low note loudly, the fundamental has to be REALLY loud as THAT is all we have to work with.
3. Resonators - rather than writing it here, I'll direct you to where I've already written it. Go to this sales page here:
And scroll down to the FAQ section. I've written it there. I would add only this. Whilst I would admit that theoretically there is potentially SOME subtle differences - in a practical test it is not heard. I have had the situation where there are two marimbas - identical in every way except the resonator material - sitting next to each other on a stage. When actually playing them you can MAYBE hear a little difference although you wonder if you are imagining it. In a closed eye test from any point in the room you just cannot tell which instrument is being played. So whilst some would argue for one material over another, I would say it's way more worth concentrating on other things which have a WAY bigger impact on the sound like the bars / suspension etc.
4. Never tried Velcro, no. I can see that it would not be suitable as a permanent fixing method but also that it would work quite handily as a temporary fix like you say.
Hope this helps you Alan.
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answers by Jim MCCarthy - 28/02/2008
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