Chromatic for Diatonic Players: Keep that Slider Slidin’- Part 2
By Winslow Yerxa
In the last installment I described the various types of mouthpiece/slide assemblies found on current chromatic harmonicas. This time we’ll look at the differences among the actual sliders and describe ways to keep your slider clean and sliding well.
Straight and Cross Tuned Sliders (and the Reeds Behind Them)
Look inside the mouthpiece holes of the two harmonicas below and you’ll see two different types of slider. The one on top has all the upper halves of the holes open, while the one on the bottom has the upper half alternating with the lower half as you look from one hole to the next.
The top one is straight-tuned and the bottom one is cross-tuned. Aside from interesting visual patterns, these two arrangements have three important differences:
- The holes in cross-tuned sliders are wider.
- You have to press the slide in farther on cross-tuned instruments.
- The reeds are located differently on cross-tuned instruments.
Manufacturers claim that the larger holes in cross-tuned sliders deliver more air to the reed, allowing for a bigger sound. Some players believe this and experience it, while others with engineering minds debate the claim, citing calculations showing that the difference in actual air volume makes a negligible difference in sound produced.
I once had the opportunity to play two instruments that were identical except for one thing—one was straight tuned and the other cross-tuned (the harmonicas were examples of the Suzuki Fabulous 48, which comes in both configurations). Switching back and forth and listening as I played, the straight tuned instrument seemed to have a brighter, more immediate sound while the cross tuned one seemed to have a sound with more “oomph” and less bite.
I have taken a single instrument and recorded it, fitted once with a straight-tuned slide assembly and once with a cross-tuned assembly. You can hear the two in the following examples. Can you tell the difference? (If you want to know for sure, you’ll have to ask!)
Click here to listen to Example 36-1
Click here to listen to Example 36-2
I suspect that from a manufacturing perspective, fewer pieces are ruined when making cross tuned sliders because there is more metal separating the holes that are stamped with hundreds of pounds of force into the thin metal of the slider.
However, the difference in slide ‘travel”—how far you have to press in the slide button to change from slide-out notes to slide-in notes—can be very significant. Travel varies considerably among harmonicas. Straight tuned slides tend to have a travel of around 5 millimeters and cross-tuned slides travel somewhere in the 7 to 10 millimeters range. Even these tiny differences can feel huge to a player who may have to move the slide in and out with precision five or six times a second! I’ve noticed that less than a millimeter will make a difference for me; I have to take some time getting used to an instrument with significantly longer or shorter travel than I’m accustomed to.
Where the reeds are located is the third difference and is only important if you need to work on a reed—tune it, unclog or realign it, replace the reed or its windsaver valve, or set reed action. Then you really need to know where the reed is on the harmonica.
On a straight-tuned chromatic in the key of C, all the notes of the C major scale are on the top reedplate—you can tell by looking at the open holes when the slide is out. Likewise, all the notes of the C# major scale are on the bottom reedplate. Now, just remember which reeds are blow and which are draw, and you can find the reed you need to work on. The diagram below shows the arrangement of reeds on the reedplates for a straight-tuned harmonica.
However, on a cross tuned chromatic, the notes of the C scale are on the upper plate only in odd-numbered holes—just as the open holes in the slider would indicate—while the notes of the C# scale are on the upper plate only in the even numbered holes. If this is confusing, our next diagram will help the next time you need to work on your C chromatic
Keeping Your Slider Sliding
Slides are subject to all sorts of ailments:
- Freezing in place
- Sticky, sluggish action
- Leaking air
- Unwanted noises
The last three items can benefit from the assembly and disassembly procedures I’ll describe later in this installment. In a future installment I’ll go more fully into some of the tweaks that can result in further improvements.
The first couple of items have two possible causes: sticky residues and pressure from surrounding parts.
Keeping the Slide Clean
Sticky residues are a fact of life: You breathe through the same porthole that you use to eat and drink, and your body naturally produces sticky substances that get into the airstream.
Your first line of defense is to play with a clean mouth.
- Never play while eating or drinking anything but water.
- Always rinse your mouth, at a minimum, before playing.
Your second line of defense is keeping the slide clean and moist.
- Before playing, inject a little water or saliva into the ends of the mouthpiece, and gently jiggle the slide up and down before attempting to press it in.
- During your playing session, spray the holes with water mist from a small sprayer. (A tip of the hat to Tom Stryker for this one).
Warning: Do not lubricate the slide with anything oily or sticky. This will get inside the harmonica and gum up the valves.
Your third line of defense is to keep the harmonica away from foreign particles such as lint, dust, sand, or other debris that can cause the slide to grind or stick. After playing, tap moisture out, let the instrument air dry, then store it in its box or pouch to keep it from contact with foreign matter.
Non-Invasive Rinsing Procedure
You can rinse the slide assembly without disassembling the harmonica. However, you want to keep the rest of the harmonica from getting wet. This keeps the valves from getting wet and sticking, but for wood-bodied harmonicas it’s especially important not to get the wood wet, as it can warp and crack. To do this:
- Take a shallow pan that is wider than the harmonica, and fill it with warm water no deeper than the mouthpiece assembly.
- Place the harmonica, holes down, in the water, so that only the mouthpiece and slide are immersed.
- Wiggle the slide in and out several times.
- Keeping the holes facing down, lift the harmonica out of the water.
- Tap the holes on a cloth held in the palm of one hand. Tap all the holes, and tap with the slide both out and held in, to remove all moisture.
- Test the slide action.
- Repeat the dipping and tapping-out procedure if needed.
However, from time to time you may need to completely disassemble the mouthpiece assembly and clean the slide, the backing plate, the slide cage, and the mouthpiece.
Disassembling the Mouthpiece
To disassemble the mouthpiece:
- Use a screwdriver of the size and type as the two mouthpiece screws.
- Press gently on the middle of the mouthpiece as you unscrew each screw.
- Once the screws are free, gently lift the mouthpiece by the ends.
- Look for the bumpers—the pieces of plastic tubing that wrap around the screws. These may adhere to the screws, stay nestled in the rest of the assembly, or fall off the screws.
- Remove the screws and bumpers and set them aside in a jar lid or other shallow container.
- Gently lift the remaining parts of the assembly—slide cage, slider, and backing plate. If they stick, do not use force. Moisten them and try to work them loose.
TIP: Some customizers use rubber cement to adhere the backing plate to the comb fence on plastic-combed harmonicas (this is to increase airtightness). If the backing plate is glued down, you may want to leave it in place.
WARNING: once you’ve removed it, you may notice that the mouthpiece curves upward at the ends, away from the surface of the harmonica. Not all mouthpieces do this, but this curvature is intentional, to keep pressure in the middle of the mouthpiece. Don’t attempt to change this curvature unless you’re very sure both of your metal bending skills and the effect this will have on slide travel and on airtightness.
Cleaning the individual Mouthpiece Parts
To clean the parts, you can follow this procedure:
- Lay each part on a hard, flat surface. This allows you to scrub the part without bending it. Always lay the slide with the slide button hanging off the edge.
- Use a toothbrush with toothpaste or mild soap to scrub the parts, and rinse thoroughly.
TIP: In extreme cases of pitting, corrosion, or deposits of hardened substances, you may want to use steel wool, scouring pads, or metal cleaners. Be very careful not to compromise the flatness of surfaces, and avoid removing the plating from the metal. Again, rinse thoroughly both to remove grit and to remove anything that might be toxic. Washing thoroughly with soapy water or alcohol may help to remove cleaning compounds.
- Rinse each part thoroughly with warm water.
- Air-drying is best. Avoid using cloth that might introduce unwanted fibers or threads.
Re-Assembling the Mouthpiece
When you re-assemble the mouthpiece, you can use this procedure:
- Lay the backing plate (if any) on the face of the comb. Make sure the slide is right side up—Hole 1 should have the upper half of the hole exposed.
- Lay the slider on the backing plate, and make sure the spring is inserted into the hole in the slide.
- Lay the slide cage (if any) on the slide, and make sure the tabs on the cage are engaged in the notches in the backing plate.
- Thread the screws through the mouthpiece, and place the bumpers on the screw shafts.
- Hold the screw heads in place with your fingers and lower the mouthpiece to the harmonica, and engage the screws in their holes.
Tricky Bit: You may need to press the slide in slightly to uncover the screw hole at the right end. One way to do this is the engage the screw on the left side with a few turns to secure it, then use one hand to press in the slide while you hold the mouthpiece, cage, slider and backing plate in alignment, while inserting and threading the right-side screw with the other hand.
- Once the screws are engaged, press the assembly together with your fingers. Make sure that all four slide cage tabs are engaged in the notches in the backing plate. Then examine the left end of the harmonica. The mouthpiece, cage, slide, and backing plate should all lie parallel with one another. If any part is not parallel, realign the stack.
- Check to ensure that the slide spring is still engaged—the slide should spring back if you press and release it.
- Once the screws are engaged and all parts are aligned, tighten the screws. Tighten them until the slide will not move when pressed, then back off until it moves freely. Back off by quarter turns (one-quarter of a full-circle turn).
In the next installment we’ll look at dealing with slide springs, and perhaps some simple repairs.