Tag: 1256

Deagan Aurora (part 3) (Job No: 1256)

It can be seen that I tend to employ a systematic approach to overhauling percussion instruments, and vibraphones in particular typify my methods.  Sometimes I deviate from the logical order of doing things, so in 1256: Deagan Aurora (pt 1) I looked at the damper system and in 1256: Deagan Aurora (pt 2) I looked at the whole frame.  This was just because of the way my working week fell – it was Friday late morning when I started looking at this vibraphone, and I didn’t want to immerse myself into a new project only to have to break off immediately, so I removed what I thought would have been a small element.  Anyway in this post I hope to finish the instrument by looking at the final three elements: the resonators, motor and notes.

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In the photograph above, the resonators on the left have yet to be done, whereas the resonators on the right are complete.  What doesn’t come out so well in the photos is just how dirty these resonators were.  Thankfully it was a nice summer day, so I sat outside with a bucket of hot soapy water and literally scrubbed them until they were clean, whilst hosing off the filth periodically to prevent it from baking back on.  And that was just the tubes.

The important thing about vibraphone resonators are the butterfly valves that rotate, opening and closing the tube.  The tube, as the name implies, is simply an acoustic chamber that resonates in sympathy with the second harmonic of the note under which it is hung.  As the butterfly valve is rotated it opens and closes this acoustic chamber so it cycles through being activated and therefore heard, then not.  This is what give the vibraphone its sound and presumably its name; although the name is misleading because I have no idea what the “vibra” stands for, because it is not vibrato.  It should be called an Oscillating Amplitude (Second Harmonic) Metalaphone which would have been way more cool.  Of course I could be showing my ignorance and the “vibra” could be an aspect of the inventors name as in Adolf Sax.

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The butterflies are attached to a fan shaft which runs down the length of the resonator tubes, and this shaft is driven typically by a belt connected to a motor via pulley wheels. There are other designs, but they are just marketing gimmicks that add needless complication into a simple and efficient system and demonstrate (to me) complete ignorance of the principles of mechanical engineering, a misunderstanding of the acoustics, a lack of consideration for the gigging musician, or a combination of all three. This design works, it has always worked; it is simple, rarely goes wrong, and is quick and easy to set up when assembling the instrument. I never understand why manufacturers can be bothered to put effort into developing an alternative system that ultimately is worse than the starting point unless it is simply to give them something to talk about when they are trying to sell the instruments. My “USP” is that it sounds good, oh and it has a life time guarantee.

Because the fan shaft is so long, it needs to be supported, certainly at either end, but also in one or two other places. It is these supporting bushes that introduce noise into the system, and of course that noise is amplified through the resonator tubes. I often have to make up new bushes to replace parts that are damaged or simply missing as was the case on this Deagan vibraphone.

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All of this cleaning, making parts, repairing and polishing fan shafts, aligning, etc all takes time time, and unfortunately there really is no short cut; cutting corners results in a noisy system. So after all of this work, the next stage is the motor. This is where things went wrong for me. The problem is that I am damned if I do and damned if I don’t. Because the motors are generally very old, they are really dirty and essentially operating under a 15 tog duvet of dust which means that everything gets very hot – not good. However, because everything has been getting very hot for a very long time, all the wires are extremely brittle and on the very edge of breaking down – also not good. So if I leave things alone the motor will fail and if I try and clean and service it, the motor could fail. The final element is the wiring; because the motors are invariably very old, health and safety simply was not even taken into consideration. Today things are different, I simply cannot let an electric appliance leave my workshop if I know it to be unsafe – regardless of legislation on a personal level I will not let people expose themselves to life threatening dangers in ignorance. However there is legislation and appliances need to be inspected by a qualified person, and if the wiring is dangerous, then it fails the test and legally cannot be allowed to be used.

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So all I did was to put on a strain relief system. This meant desoldering wires, threading new cables through and reconnecting. After my intention was to blank off the exposed components. This minor bit of work introduced an inconsistent fault, which, whilst trying to identify gradually became less inconsistent until it achieved permanent. Ultimately, a decision has to be made – is it really worth spending time and effort trying to fix a motor that is forty years old? The answer is no.

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The final stage of the overhaul is to clean the notes. Finger grease, beer, sweat, spittle, smoke, etc multiplied by years equals a nasty film of crud that inhibits the notes from vibrating. Unless I have be asked to tune or refinish the notes, it just a case of cleaning it all off which requires more time and elbow grease. The results however are rewarding; not only do they look a lot better, they sound so much better and respond when played. When the whole instrument is assembled and clean notes go on it is like the icing on the cake, although it is the notes that are at the very heart of the instrument. But this is not unusual, it is the same with all instruments: for instance the strings on a violin, guitar or piano make the vibrations, but it is how the rest of the instrument utilises those vibrations that is important.


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Deagan Arora (part 2) (Job No: 1256)

I’m only human; I have one pair of hands, only so much time and a limited amount of patience. After a really busy summer, I am still behind with just about everything including writing these blog posts. So I utilise waking up early to try and catch up, spending two hours writing a post only to have all the content deleted when the upload fails. It makes me want to scream I am that annoyed and consequently it takes me two days to calm down enough to try again, so here goes…

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When the phone doesn’t ring much, in addition to the work that does come in, I have the time to return to jobs that get delayed, start long overdue projects and catch up over a longer time scale. The result is always the same in that I bite off more than I can chew and end up being swamped with tasks and crisis management has to be employed. So invariably jobs take longer from start to finish, but several end all at the same time. This Deagan Aurora is an example of one of those instruments that I keep returning to over several weeks rather than working on this vibe alone from start to finish. In 1256: Deagan Aurora (pt1) I concentrated on the damper system (mainly because I had to do exactly the same job on another instrument, so I did the two back to back. In this post I will look at the frame of the vibraphone.

In the photo above, the two massive ends of the Aurora can be seen. These are held together by the central bar on which the pedal is mounted. It is quite a clever design, but in practice not that use friendly. The bar slides into a telescopic socket mounted on either board.

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This socket goes nearly the full depth of the end board and means that the two ends are kept perpendicular to the cross bar through the 360 degrees of the tube; gravity keeps the wheels horizontal on the floor and these two ends are massively heavy. Therefore with just the two ends and the cross bar attached I can verify that the ends are perpendicular, parallel and level to each other. This provides me with a second datum line (the floor (being absolutely level) is my first datum) at the top of the vibraphone.

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Now I have my datum line, I have exposed a major problem – none of the note rails are level. In the photo above, the gold on the top of the end board and the silver of the aluminium straight edge should be parallel, but it can clearly be seen that the black line gets wider towards the left of the picture, which means that the outside accidental note rail is lower than the natural outside rail. At the low end of the instrument it was the other way around and obviously they were not level down their lengths. Further investigation revealed that one of the inner note rails was above the line, depicted by the straight edge, and the other below. This is a major issue especially on instruments with a damping mechanism like vibraphones; if the notes are not flat, then there is a reliance on the felt on the damper bar to accommodate these discrepancies. This only works if the correct felt is used, which it isn’t, and silly fads like using gel will definitely not work, certainly not to that standards that my customers have come to expect. Therefore I put mechanisms into the ends and centre joints of all the note rails so that I can make the necessary adjustments and set the instrument up properly. Another obvious and simple modification that I make that I have never seen on any other percussion instrument which resolves the recurring problem that these instruments are used in the real world and not just to look pretty in showrooms and catalogues. On this Deagan Aurora, the cause is because it was made badly, but in this day and age of mass production the same problem occurs through wear on substandard materials.

The story continues in 1256: Deagan Aurora (pt 3)

Deagan Aurora Overhaul (part 1) (Job No: 1256)

The player thinks that it must be 20 years since this Aurora vibraphone was last serviced.  It feels like that long since I last posted!  Those who know me personally, will know that it is not just that I have been sitting on my hands – although there were a few moments!  I have been working on new things, which I will write about separately, but bubbling over in the background have also been a few jobs of which this Deagan is one.

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After having specific issues to resolve on the last few instruments, my remit on this Deagan Aurora is back to what I normally get, “can you sort it out please Paul?”  So when this is the case, I look at and repair, restore or modify every component.  I have a systematic approach, for example on the Aurora joining the massive ends with the cross bar is the first part of assembly, so this is where I start the overhaul.

Those massive ends don’t come apart; well they will, but only by damaging the plastic covering.  This Deagan is still looking good, so I am reluctant to do that for little reward.  Therefore it is the cross bar that I turn my attention towards, and in particular the damping system.


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This post continues with 1256: Deagan Aurora (pt2).