The Saturn Water Key
The Saturn Water Key
What's wet, messy, dribbles over tuxedos, fails at the most inappropriate moment, has bits of cork as its main ingredient, is fitted on virtually every brass instrument ever made, and hasn't (perhaps with one exception) changed design since Joshua practised his fortissimo against the Jerichoan Walls? Well, not quite, but certainly since Adolphe Sax invented the seven-belled trumpet. If you haven't guessed by now, you are not a Brass Player. Yes! It's a water key.
We've got space age titanium mouth pipes, Kevlar bells, rocket science cryogenics, precision ground valves to microns of tolerance, perturbatory analysis that would baffle Einstein, super-deluxe, go-faster booster warblers that do absolutely nothing and we still use a device on our instruments that wets our shirts - amazing.
Horror stories about water keys abound. Only recently a good friend of mine played a whole concert with his 'finger in the Dyke' when the spring broke after the first note - no Interval. If you would like to share your own personal leaky nightmare drop us a line and we'll publish it.
When the spring breaks - as they do - on a conventional water key, the cry echoes around the ensemble - 'my kingdom for an elastic band'. This being really the only effective emergency method of keeping a small hole on the player's instrument closed, thus allowing him, or her, to complete their performance.
As a brass instrument apprentice, there used to be an 'old boy' - everyone's old when you are sixteen - whose raison d'ętre was to make water key springs. There he sat, on his high stool at a bench in our factory, from 8am to 5.30pm, five days a week plus Saturday mornings, just winding springs on a little rod with a wheel at one end. To be fair, he was the First Aid man as well as spring maker, but sure as hell no one ever went near him if they'd had an accident.
Perhaps that reminiscence was the reason for me to enter and lock the door of the 'thinking room' and put the seat down. More probably, it was the absurdity of the device itself. The fact is that the brass instrument water key is the last thing a designer and manufacturer wants to know about when they've spent all their time and energy on the instrument itself.
The standard brass instrument water key usually comprises of about six parts:
A 'cast' key with a small tube brazed at right angles near it's fulcrum, with a cup shaped piece of metal, also brazed, at the non-levering end to take a piece of cork as a sealant. This casting is usually nickel plated for added strength prior to whatever finishes the instrument is intended to have.
A 'carriage', the base of which is soldered to the instrument's pipe or slide where the device is to be set. This 'carriage' has two raised prongs - one threaded to take the screw pin connecting the 'carriage' to the 'key'.
A piece of brass shaped like a tiny Vesuvius which is also separately soldered onto the instrument and then drilled through into the pipe - usually, although seldom in the case of one British manufacturer, at a low point on the bend.
A spring, shaped like a convoluted mediaeval torture device bisects the key, its points pressing against the carriage keeping the cork filled cup at the end of the lever firmly - or it should do - airtight over the Vesuvius.
Gravity then takes over. As the water (saliva), beer, tea (tea?) in the instrument seeks the low point, inside the pipe and into the volcano, it awaits the player's decision to press the lever and release the liquid. This is usually preceded by burbling noises, especially on low notes due to the partial parting of the cork from the volcano. Even when open, the cork still partially covers the hole, and when the player blows through the instrument to clear it, the water hits the cork, its owner and his colleagues simultaneously. Ironically, there's no discrimination. The amateur player gets just as wet as the virtuoso.
From a manufacturer's point of view, constructing and fitting a water key is just a nuisance. Levers, carriages, castings, electro-plating, screws, cork, aligning the device with two reference points onto the instrument, fitting the spring... And springs have lives of their own. On Monday mornings their pointed ends stick into fingers. Trombone springs nearly always attack first. They're much stronger and have no morals.
From a scientific viewpoint, is it really a good idea to have an air filled cul-de-sac in an instrumental vibrating air column? The one I'm referring to is the chimney (volume) of air between the pipe of the instrument and the surface of the cork blocking the 'volume'. This is sometimes blocked by pre-shaped rubber or cork, but somewhat inaccurately.
One of Mr. Schilke's London lectures demonstrated the ability to play certain notes on his 'C' trumpet with the water key open. This technique, which is standard recreation for all bored saboteur-minded brass players, was to demonstrate that as long as the vibrating air column had a node at the water key point, it didn't matter what shape the tube was. But we've found that by leaving a burr inside the tube after drilling a hole for the water egress, experienced players detect a 'blurring' of certain notes. Or even a tendency for some notes to split. Presumably these are notes with antinodes in the water key area.
The single design exception to the ancient lever water key is the 'Amado' water key. The designer of this device had almost certainly travelled the same wet route as we did. Instead of levers, carriages, wells and such junk, Mr. Amado (can anyone tell me the history?) opted for a spring enclosed piston blocking the instrument exit hole in the closed position and opening when the operator pushes the extension button. Nice idea - except that pistons still need connecting rods that have to pass directly across water exit holes in the instrument, once again impeding fluid release. Also there is still a discrepancy of bore, either vibrating or non-vibrating, depending on the frequency of the played note, underneath and around the piston area.
So, these were the reasons to take a new look at what basically is a plugged hole in a brass tube. And here was the brief: To design and construct a more efficient, easy to use, easy to make mechanism to release water from a brass instrument, the construction of which offers minimum pipe distortion and maximum efficiency when activated - i.e. no 'volcano', corks, pistons etc. locking egress. The device to be preferably 'house-trained'.
It was immediately apparent that better brains than mine had been there well over two centuries ago and used the maxim 'if it works, don't fix it'. Spectres of ancient spring winders appeared, with forging Nibelungs fettling away producing works of hydrological art still seen on instruments today. It was also apparent that the priority was to use mass production manufacturing techniques.
Would a 'mushroom' device with an inverted seal work? No! It would still need a rod, which would get in the way of exiting fluids. A piston maybe, with a plug that actually went 'inside' the instrument when depressed? Same thing, back to square one. Time to talk to greengrocers, car salesmen, astronauts - if I knew one - and my friend the road sweeper on the Broadway. They'd know.
The birth of the 'Saturn' water key began with the background clatter and hiss of CNC machines in my friend Brian's production-engineering factory. Always heralded by an aural fanfare when parking my motorcycle - to musicians, I'm and engineer, to engineers I'm a musician. Yes, he thought he knew what was needed. Nothing to block the exit hole when open; can be activated in any direction 360° left or right handed; minimum deformation to the fixed tube when closed - the whole thing designed for mass production - and no cork. Plus a complimentary flying pig with every purchase.
And so the 'Saturn' water key evolved. One fixing to the instrument.
Press on the ring in any direction (any hand) to dislodge the stainless steel helical sprung ball from its airtight seating. Virtually clear route from instrument to floor. Release ring and the stainless steel ball returns to its seating once again to make an air-tight seal.
Perhaps the ghosts of my old spring winder and his fellow craftsmen centuries earlier smiled on us, and will stop walking at night soon. It would be nice to know they look favourably on their modern colleagues. And who knows, our new Water Key might even prove popular.
(c) 1999 Medici