Let’s Talk Trumpet — Waterkeys & Dump Slides (Part II)
In the first part of this blog post, we focused on the important aspects of waterkey assemblies and their different means of operation. We then discussed the approach to developing a waterkey assembly and how one might effectively design one. This then led up to the following questions that are yet to be answered:
- What design is most effective for dispensing condensation?
- What design does not negatively affect the acoustics or overall dimensions of the instrument?
As I left off in the previous blog post, I mentioned that these questions are intended to bring out players’ personal preferences, and what these players seek to achieve with the waterkey and its overall functional purpose. So now, let us begin with the comparisons between the four major categories of waterkey assemblies!
On one side, some players prefer to have a push button, passive, or rotating waterkey assembly because it eliminates having a condensation dispensary chamber in the assembly (i.e., the waterkey “pip”), like on the lever waterkey assembly.


Additionally, these players tend to prefer pressing a push button, actuating a rotationally fastened device, or even not having to actuate any devices in order to dispense collected condensation—such as with a passive waterkey assembly. There can be, however, potential hindrances in the performance of condensation dispensation for the push button, passive, or rotating assemblies—depending on the results of waterkey placement or location on the instrument, or even the dispensary hole’s drill size. Poor waterkey placement or having too small of a dispensary hole can lead to condensation passing over or not properly dispensing from the intentionally installed waterkey assembly. The same hindrances can also affect lever waterkey assemblies.
On the other side, players might prefer to have a lever waterkey assembly because it provides a “traditional” feel or balance to the player when it comes to weight, size, and functionality. In some instances, players can make customizable adjustments to their lever waterkey assemblies that can improve the horn’s overall response. These adjustments can include:
- Relieving tension of the lever waterkey assembly by loosening the hinge rod screw
- Lessening the spring torsional strength by downgrading it to a lighter-weight spring
- Changing out the waterkey cork material (i.e. natural cork, neoprene rubber, synthetic cork/foam [ex. Valentino “Opti-Kork”], gasket/rubber cork [ex. MusicMedic “TechCork” or Kraus “Gummi-Kork”], etc.)
Doing these slight modifications and adjustments can improve the response of the instrument, as well as relieve any accumulated stress that could reside in the lever waterkey assembly.

Now we must mention here, the condensation dispensary chamber on lever waterkey assemblies, whether short or tall in height, can have an effect on the acoustical properties of the instrument by obstructing the flow of nodes and antinodes throughout the tubing of the instrument. As the longitudinal waves are formed along the length of the instrument’s tubing, a drilled hole in the tubing—used for condensation dispensation and leads to a conditional open end of the instrument—can produce adverse resistance to the player and an unbalanced response of the nodal tones.

Besides these acoustical drawbacks that the lever waterkey assembly might have within the waterkey pip, the pip provides a good amount of condensation dispensation due to its effective design and size. Since it has stood the test of time for performance and overall functional purpose, the use of a lever waterkey assembly is still highly utilized by many big-name manufacturers—such as Bach, Yamaha, Schilke, and more.
To overcome some of these drawbacks for lever waterkey assemblies, job shop manufacturers and discrete production line manufacturers have come up with alternative waterkey cork options that can essentially “plug” the inside dispensary chamber of the waterkey pip. Tying that to the previously mentioned customizable adjustments that players can make to their lever waterkey assemblies, players are encouraged to pursue changing out the waterkey cork material to a different option that improves the horn’s overall acoustical response in one way or another. Changing out the original waterkey cork to a waterkey pip “plugging” option is, in my opinion, the most “acoustically effective” choice to incorporate into a lever waterkey assembly.

The first trumpet manufacturer, to my knowledge, using this “plugging” concept was Renold O. Schilke starting back in the 1960s. Schilke Music Products, unfortunately, no longer offers this option as a standard feature on their trumpets, cornets, or flugelhorns. It is unknown when Renold stopped incorporating these plugs into his line of brass instruments.
In the early 2000s, Yamaha came up with their own version of the waterkey pip-plugging cork option. However, Yamaha slowly shifted away from offering these as a standard option for their trumpets, cornets, and flugelhorns. These “Trumpet Pro Rubber Waterkey Stops” from Yamaha are still available and can be ordered through most music suppliers today.
Another manufacturer worth mentioning here is the Swiss-based company, Willson—now owned by the Eastman Music Company. Willson makes their own version of the waterkey pip-plugging cork option, but the corks are sized and fit primarily onto their popular euphoniums and tubas.
At the present time, the most recent waterkey pip-plugging cork option to appear on the market is the Bájoc Harmonic Waterkey Plug (more info can be found here). The same pip-plugging concept applies here, but a brass plug is seated into the cup of the lever waterkey and a gasket cork material O-ring fits over the brass stem. This provides an effective seal around the waterkey pip while allowing for the pip to be effectively plugged, resulting in no air leaks and a less obstructed pathway for the nodal tones to travel. Not to mention, the Harmonic Waterkey Plug acts as an acoustical harmonic balancer weight for the waterkey assembly due to the properties of the brass plug and the gasket cork material O-ring—resulting in the nodal tone energies being conducted inwardly towards the valve block and not dissipating outwardly from the slide crook.
With all of the abovementioned waterkey assemblies comes all different types of maintenance and repairs for each of them, which will influence players’ choice of waterkey assembly. To list some examples of preference, would players rather risk:
- Offering “blood sacrifices” to the trumpet trying to install a coiled torsion spring onto a lever waterkey assembly;
- Messing with a small, fragile C-clip; or
- Having to deal with unusually long shipping and handling times to get special assembly replacement parts?
Of course, there are several factors at play here. Depending on the assembly, maintenance and repairs can include changing out:
- Rotating — broken coiled compression springs, worn-out ball bearings, rotationally fastened or assembly housing components;
- Push button — broken coiled compression springs, small pistons, C-clips, retaining disc plates (threaded or non-threaded), and assembly housing components;
- Passive — water filters or wicks, rubber O-rings, and assembly housing components;
- Lever — broken coiled torsion springs, worn-out corks, damaged hinge rods, lever waterkeys, and broken/missing pips and saddles
What type of waterkey assembly do you prefer? Have you had any good or bad experiences with one waterkey assembly or more that are listed (or not listed) here? Leave a comment down below, we would love to hear your thoughts!