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Dave Werden and Heavy Bottom Caps
Adjustable Bottom Cap (ABC) - Heavyweight 4th Valve Bottom Cap
Reviewed by Dave Werden

On my forum and other places, euphonium players have discussed the benefit of replacing the standard bottom cap of the 4th valve with a heavier version. The first I heard of this is when I was a Sterling artist. They sent me one for my Sterling Virtuoso and I liked it. The tone and centre seemed a bit better for most music. For music that was light and "bouncy" I tended to prefer the standard cap (but that may have just been in my head). Regardless, it was easy to change the cap when I wanted.


More recently I learned of a line of heavy caps made for most valved brasses: the HBC (Heavy Bottom Cap) product. It was designed by musicians and beautifully made. They had a couple of different weights available, and I enjoyed using each. My choice seldom brought me to the original cap.


The clever folks who brought us the HBC have created a new, improved cap that is adjustable. Now, in one slick assembly, you have a choice of four different weights. At its "worst" changing to the heavy cap is no harder than before - just unscrew the bottom cap and screw on the new one. But for some of the adjustments, it is not necessary to uncap the bottom of the valve.


The assembly consists of four pieces. The top piece screws onto the valve and must always be part of the mix. That piece by itself adds enough weight to be noticed by a perceptive player and maybe what some people would use. The next piece to be added must be the bottom part (gold in the photos below) because it has a threaded shaft to fasten to the top piece and to help secure the middle pieces. The options with this assembly are:


Top only: 56 grams

Top and bottom: 114 grams

Top, bottom, and 1 middle: 157 grams

Top, bottom, and both middle pieces: 200 grams


The weight with all pieces is heavier than the previous HBC heavy cap or my heavy Sterling cap. Here is what they look like in an "exploded" view:

Heavy Bottom Caps

Here is a sequence of photos showing the options on my own Adams E3:

Heavy Bottom Caps
Heavy Bottom Caps
Heavy Bottom Caps
Heavy Bottom Caps

Below is a video where I play excerpts back to back between my standard Adams cap and the ABC (fully loaded). As I was editing the audio, I thought I would use some graphic examples to show the output differences. Here is a graphic that tells a little story. I changed Audacity's colours to help make this clear. This is my first excerpt from the video, mixed from the standard and heavy cap. The dark blue shows the peak "measured" level (as far as I understand it). Normally there is an inner part that is a lighter blue. Audacity says: "The light blue part of the waveform displays the average RMS (Root Mean Square) value for the same group of samples. This is a rough guide to how loud this area might sound... I take that to mean the light blue area is most important to the human ear.


I re-coloured the light-blue area to red. Then I overlayed a different sample with yellow. Red is from the ABC full cap, and yellow is from the standard Adams cap. (FYI, the dark blue areas are identical visually.) The difference between red and yellow represents the added sound from the ABC.

Heavy Bottom Caps

Obviously, the difference is small, but it is still audible. However, an even larger difference to me is the way the horn plays. It feels more solid with the ABC cap. The ABC arrived the day before I left for my recital at GPRTEC. The previous week I had put on the heavy HBC because I was doing a couple of pieces that needed all the energy I could put through the horn. That is where the difference is most noticeable. So, when the ABC arrived I put it right on the horn with no hesitation. I can't swear I noticed the little bit of extra weight over the HBC, but it sure felt nice and held up to whatever I fed into the horn.


It has been established that mass affects sound and response on a brass instrument (or mouthpiece). The effect could be either good or bad, I suppose, but in this case, I see no downside unless you just want a lighter feel in some specific cases. If so, removing some weight is a 15-second job with this product.


The ABC people are known for outstanding quality and customer service. I urge you to try one of these caps. The investment is not large (cheaper than most mouthpieces), and there is a 30-day period to decide if it's a keeper.


In my own case, I'm sure I will keep the ABC on my horn in one configuration or the other. I'll keep the top piece on - it's lighter than the heavy Adams cap I usually had on the horn, so it should not prove too heavy for any use. And then I can quickly and easily add 1, 2, or 3 extra pieces depending on my chops and the music I'm playing.


And this is my video with the comparisons. As usual, I played all excerpts with the standard cap and then all excerpts with the heavy cap. Then I used my video editor to alternate caps with each excerpt. That ensures that I am not continually adjusting to a different setup with each excerpt.

Heavy Bottom Caps

What our customers say about us…

Heavy Bottom Caps

A superbly engineered piece of kit really makes a difference in centring notes in all registers. I have settled with mine on the 3rd valve of my 1980 Sovereign cornet and can't wait to have one on my Stomvi trumpet!! Highly recommended – Sharon M

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