Tag: Adams

Adams Timpani Repair (Job No: 1325)

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It is unusual considering the age of these drums that certain components are made with more consideration for frugality than quality.  I remember when I last saw these drums that I had a number of difficulties with the fork pressing (Premier’s name for the part), which is the lever that lifts the sleeve which disengages the clutch from the underside.  Well seven years have gone by since then, and the drums have been giving good service, but recently these components have started to fail and cause problems, so I have the drums again to come up with a solution.


What is evident from the video is that the choice of how Adams made these components is dubious.  As I mentioned in the video, the British Isles leads the world in engineering, always has and if the government get their head out of their arses it always will.  So of course Premier made the parts the proper way which is why 50 years later the design has not changed.  Adams are copyists but seemingly things have always been done on the cheap.  Short term gain.  The lack of engineering knowledge to come up with a good design is one thing, but the worst element of these components is that they are badly made.  This causes lots of problems when I come to copy them, because unlike them, I make things square/perpendicular/paralell/etc as appropriate.  Therefore the job immediately becomes a lot more challenging.

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Adams Universal Timpani (Job No: 1263)

When I overhaul a set of timps, there is a lot of work involved over a period of days or even weeks. My approach is to fix everything properly; I am after all a professional and that is what I am being paid to do. However not everyone is as conscientious, and in the end, you get what you pay for. So when I work on timpani, I am fixing problems associated with wear and tear, and the dogs dinner that the previous person made of the job. The posts on timpani pick out examples of problems I encounter, rather than me writing, and you reading the same thing every time I do a set of timpani (which is why I have coloured this bit blue).

When these Adams copper universal timpani were brought in to be overhauled, the customer was complaining, amongst other minor issues, about the drums buzzing.  As soon as I heard the drums I knew what the problem was:

Adams universal timpani are built using the same method as Ludwig timps; the bearing edge is formed from a steel extrusion which is then fitted into the bowl.  In this case the bowl is made of copper, but the same process is used with their fibreglass timpani.  Fibreglass bowls are stuck to the metal ring with the same polyurethane resin (probably) used to make the bowl, however both Ludwig and consequently Adams have not used an adhesive but a mechanical fixing (pop rivets) to make the joint between a copper bowl and a steel hoop.  The big problem is that copper bowls are spun into shape, and there is always a discrepancy between the size of the bowl and the steel bearing edge hoop.  Spinning metal is a bit of a black art, so regardless of mechanical automation the size of the bowl will (and do) always vary.  Rolling hoops is also one of those things that is difficult to do exactly.  Therefore, this gap is almost bound to happen, so paper tape is used to fill the gap prior to riveting the bowl in position.

The principle of this method is a nice solution, but the application of the technique employed, by which I mean the use of packing tape, is not something that I would do.  Being brutally honest, I cannot give conclusive, evidence based, acoustic arguments as to why is it a bad idea, but my gut feeling (and experience?) makes me think it is.  There is a further problem of electrolytic corrosion – the copper of the bowl and the zinc plating on top of a steel hoop, are all joined with an aluminium rivet.  Now this isn’t a major problem, but why would you even introduce it into the equation?



The really bad creak on the 26″ timpani turned out to be in one of the tuning nut boxes.  This was difficult to find, and awkward to solve.  It is one of those problems that I will have to look out for when I do this type of timp in the future.

-1. Rock, roll and twist again?

This post is part of My top ten bad designs series of posts.

Percussion instruments are three dimensional objects, so in order to effectively describe what I am looking at when I see design problems, below is a diagram of the three axis on which measurements are made.

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The X direction of movement is forwards and backwards.  The Y direction is left and right.  The Z direction is up and down.

However musical instruments don’t just exist on paper, they are used in the real world, and thus are subjected to forces that are also three dimensional.

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These forces are called Roll, Pitch and Yaw.  They are measured in degrees around their respective axis, and I have colour coded them for clarity.  For example, Roll (in green) occurs when an instrument wobbles front to back, it is measured in around the Z axis.  Pitch is one that wobbles side to side.  Yaw is an instrument that has a note bed that rotates when viewed from directly above.  In this post I am looking at roll.

Paul the Porter, and Preschool Paul are going down to the park.  As they approach the see saw, they notice that it is balanced horizontally on its base.

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Preschool Paul loves the see saw, he knows all about how, when on side goes up, the other side goes down because it is only fixed in the middle.  Now imagine that the see saw is the low end of an instrument; as the naturals go down, the accidentals go up.  This is roll. 

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Oops!  And here it is, our first example of bad design – a Bergerault Pedal Glock with a central leg at either end.  Just like the see saw above!  Now glockenspiels may not be very wide at the low end, but they are wide enough, and certainly heavy enough for this central leg to be a weak link in the design.  Consider also that it is a “pedal” glock, so there is the additional problem of moving parts within the damping mechanism that need to operate efficiently.  In my professional opinion I give this instrument no chance of surviving for the long term.

Even Preschool Paul knows that standing on one leg is a recipe for disaster.  Instead he stands with his legs spread wide whilst holding his heavy school bag above his head.

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Now this as we all know is solid and stable, and on paper looks like the perfect solution to roll.  However, if Preschool Paul removes his shoes and stands on a polished floor…

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With socks sliding along a polished floor, his feet slide apart.  Substitute the feet for wheels, and make the centre of the X the weakest part…

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Oh look, we have an Adams marimba using a design that is featured on just about every one of their instruments.  A design that is fundamentally floored in concept and the end result is hundreds of instruments all over the place that suffer from dreadful roll issues.  What is more, because the same components are used on all of their instruments, the bigger the instrument, the bigger the problem.

Bergerault use a capital I as the basis of their design – I for inadequate.  Adams use an X for exceptionally bad.  Any instrument design that transfers the weight of an instrument directly through its centre line is always going to be exceptionally bad and the resultant instrument is going to be inadequate to withstand the forces applied.

So what is the solution to preventing roll?  For me, simple is best, and the simplest solution is a square.  The only decision is either solid or hollow.

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The problem with a solid end, like the Deagan Arora (above) is weight, so I mainly go with a hollow square, ie, two legs, the bottom transom with the casters attached, and the top defined by the note bed.  In order to maximise stability, I make the legs as wide as possible, even splaying the legs out at the narrow end to make a trapezium.

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In the next part of this series I will look at pitch, which is when the instrument rocks from side to side.

Adams Universal Timp Problem (part 2) (Job No: 1243)

This post follows on from Adam’s problems (pt 1).

So day one was mainly spent setting up the drums, and making the bottom blocks.  Today starts with finishing the installation of the other two blocks, before making more components.

The original central tuning rod has been removed from the pedal, and is now actually central held by a guide block.  So now I need make a secondary linkage to join that rod to the pedal.  I still have an attachment on the pedal, but nothing on the central rod, so this is where I start.

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Going through the photos, I take a length of brass stock and the rod end which will go on the end of the linkage rod from the pedal mark everything up and drill lots of holes in it.  (There are an awful lot of Rod’s around!)  After the smaller perpendicular holes are drilled, the pieces go in the lathe to have the longitudinal hole drilled.  The fixings holes are tapped, then the longitudinal hole is reamed to make sure it is round and will fit nicely on the central pull rod (There is only a 0.02mm gap all around so it will be tight).  Lastly the components are preassembled.

Next I make the linkage rod which is simple, I just have to run a thread on the end.

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Finally I can assemble the parts on the first drum and check that I have all the clearances, which I didn’t.

The problem is that manufacturers make product and forget that they are making musical instruments.  A lot of effort is put into making new ranges of more, essentially shit instruments, in an attempt to generate the desire to buy in a limited number of consumers.  Very little effort and value is put on the making and assembly of those instruments.  Cheap materials are used wherever possible, and because people are expensive, the cheapest possible labour is used.  So your pride and joy was probably assembled by monkeys, the dregs of society who get pissed at lunchtime and are still high the morning after.  They work for a wage packet, they don’t give a toss about whether the holes are right, it’s the near enough attitude, and near enough is not good enough to make something that makes musical noises.

So when the bowls are put on the cradles, they can be out of alignment by over an inch.  I can compensate, or remount the bowls with new holes.  I choose to compensate.  So in this instance I had remount the connection on the pedal, then make another rod, then further modify the pedal, then reassemble to check, disassemble, modify the pedal………………………..

The final part of this job is Adam’s Problems (pt 3)

Adams Xylo Tuning (Job No: 1071)

Another xylo in for tuning.
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There is some edge damage on the accidentals in the middle of the instrument. Close up below:
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The white residue is superglue – precisely the wrong thing to use. Although it is available in different viscosities, the most readily available brand is way too thin, and penetrates too readily then dries and crumbles internally. Furthermore, nothing else sticks to it including finishes.

As each note arrives at its first tune, it is inspected for damage.

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Difficult to see, but at the right of the arch, the edge is splitting. This needs to be broken out – glueing is just not going to fix the problem, the crack could be deeper than can be seen from the surface.
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As soon as the investigation starts, it can be seen that the splits are deep.

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First I break out fibres with a knife, then I often cut them away on the sander. Next I rasp the surface using a random cut rasp; this picks up any residual loose fibres. Then file and sand it smooth ready to be tuned and finished.

However, this note was still dead, a sure sign that there is a crack. A face crack was found:
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Again, this has to be picked out to see how deep the crack is:

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Looks drastic, but the note is dead, so there is nothing to lose. This just lifted out, but all around the wood is just falling apart. In for a penny, in for a pound…

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This demonstrates exactly what I mean about internal damage. This is a very badly damaged note – I suspect that it could have been caused by bad seasoning of the wood.

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It is clearly deep, but the note is now resonant, and therefore can be tuned and played until a replacement is obtained. Also observe the direction of the grain on the end of the bar, not ideal especially on xylophones.

Adams Marimba Tuning (Job No: 1069)

A west end show is going on tour and they have a marimba tuning problem; the marimba is tuned to A440Hz, but the musical samples are recorded at A442Hz. So the notes have come to me for re-tuning.
During the first cycle of tuning, I make a record of where the notes are presently, the results are below.

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In the graph, the two smooth lines represent what the tuning should be, and where I need to raise the pitch to. The wiggly lines show that the tuning of the notes is actually all over the place.
The biggest problem area is the third partial which is consistently flat.

In simple terms, to raise the pitch, the note needs to be shortened in length, removing material in the centre of the note increases the flexibility of the bar, which lowers the pitch. It is harder to raise the pitch than to lower it, furthermore, shortening the length affects all the longitudinal harmonics, whereas harmonics can be somewhat targeted when tuning down.

Therefore, I raised the pitch of these notes so that all the harmonics were at, or above the target pitch, then the harmonics that were sharp were brought down into tune.