I read a lot of posts on Facebook from people who have bad experiences with harmonicas right out of the box. These people complain that the harp is out of tune out of the box (which I agree is bad), reeds break (FYI, you’re blowing too hard), the harp goes out of tune quickly (did I mention that you’re blowing too hard?), and/or that the harp’s response is uneven, perhaps to the point where some reeds don’t play. The last problem is something that can occur with any make or model of harmonica (short of a full-blown customized harp), and it’s also something that anyone, even a novice, can do something about at close to zero expense. Doing so is economical and empowering. Economical because a harp that doesn’t play right out of the box can often be made to play really well with very little work. Empowering because getting more control over the way your instruments play puts you in charge of the harp, not the other way around.

Why Do I Need to Set Up My Harp?

First a little bit about why any harmonica, high or low-priced, might need some setup work out of the box. The question of whether a harp is properly set up depends a lot on how the owner of that harp likes to play. A harp might come out of the box perfectly set up for overblowing, but the owner might be disappointed because she wants it to respond better to loud playing. How you like the harp to respond is a personal thing, and mass-production can’t anticipate your preferences.

Further, certain setup processes are just not feasible in a mass-production environment. These processes aren’t difficult for a human with certain skills, but they’re tough for a machine, and performing them would drive the price of an off-the-shelf harmonica sky high.

So if you want the kinds of tweaks that we’re about to discuss—and you really should—then you have two choices: buy from a customizer, or do it yourself. I’ve done both with good results. But it’s a lot less expensive to do some simple, effective things yourself. The tweaks we’re about to discuss are easy to do without specialized tools, and it’s hard (in one case practically impossible) to screw it up.

Tweak #1: Flat-sand the draw reed plate.

Tools required:
small screwdriver (usually Phillips), 220 sandpaper, flat surface

Time required: 10 minutes or less. Most of that time is spent unscrewing the cover plates and reed plates, and screwing them back together after sanding.

Skill required/Risk: Zero. If you can use a screwdriver, the chance that you’re going to do this wrong is close to zero, and the chance that you’re going to harm the instrument is closer to zero.

Why it matters: If a draw reed plate—the one on the bottom side of a typical diatonic harp—isn’t perfectly flat where it meets the comb, or if the comb isn’t flat, air will leak through the gaps between the reed plate and the comb, reducing the volume of the harp and its responsiveness to breath pressure. Flat-sanding the draw reed plate makes the harp louder and more evenly responsive. Flat-sanding the draw reed plate is all that’s needed on a harp with a chambered plastic comb, like a Lee Oskar or a Special 20. On something with a solid comb, like a Manji, a Kongsheng, or a Seydel 1847, flat-sanding the draw plate side of the comb is necessary too.

How to do it:
Just look at the video below, from Andrew Zajac’s YouTube page, go get the tools, and get going. It’s very, very hard to damage the instrument with this process. Occasionally I push down on a draw reed or two while I’m moving the draw reed plate back and forth on the sandpaper, but I just poke the reeds with a paper clip or something to free them up when I do. (That problem doesn’t occur if you’re careful to place your fingertips somewhere besides right on top of the reeds.)

Note: at this point you’re probably asking why you shouldn’t flat-sand the blow reed plate too. The answer is that the side of the blow plate that meets the comb has the reeds welded or riveted to it, so sanding the plate would damage the reeds. There are other procedures to straighten a blow reed plate, but those require special tools and more capability for the tweaker, so we’re not going to talk about it here. You’ll get plenty of reward for the time and effort you put into the draw reed plate.

Tweak #2: Adjust the reed gaps.

Tools required: small screwdriver (usually Phillips), toothpick/paper clip/anything else that’s thin enough to clear the sides of the reed slots and strong enough not to break when you push on a reed.

Time required:
10 to 20 minutes.

Skill required/Risk: it is possible to damage a reed by attempting to manipulate its gap, for example by pushing so hard and quickly that the reed, which is essentially a spring, is deformed, potentially to the breaking point. Skill is expressed in terms of careful attention to reed movement while changing the gap.

Why it matters: A reed gap is the distance between the tip of a reed—the free end—and the sides of the slot it sits in. When reed gaps are set high, the reed responds to very loud playing, and overblows are difficult or impossible. If the reed gaps are set WAY high, softer notes might not play at all. If the reed gaps are set very low, meaning that the tip of the reed is just about on a level with the sides of the slot, the reed may not play when you hit it hard. As you can see, setting the gaps is about personal preferences for how the harp responds to breath pressure.

How to do it: Start by using the screwdriver to remove the cover plates, exposing the reeds. Use the gapping tool—your paper clip or hairpin or actual gapping tool–to push on the middle of a reed to widen or narrow the gap. I recommend that you begin by setting reed gaps on the draw reeds (the bottom reed plate) to about the thickness of the reed. Then try playing the draw notes to see how you like the response. (A pair of spring clips that you can use at each end of the harp to hold the reed and cover plates on the comb without screwing everything together is very useful for quickly repeating tests.) If a reed seems slow or weak in its response, open up the gap by pushing on the middle of the reed and test again. Repeat, widening or reducing the gap as necessary, until you get the response you want from the reed.

Small changes can make a big difference in response, so try not to make big changes as you adjust. In fact, you can break off a reed if you bend it too far and too quickly while you’re setting the gaps, so be careful about how much pressure you apply. Then repeat with the blow reeds. When you’re done, screw the reed and cover plates back on (making sure to make the reed plate screws finger tight and no more to avoid deforming the reed plates) and enjoy.

By the way, the potential for overblowing a harp depends a lot on how it’s gapped. For overblowing, set the draw reed gaps on holes 4-5-6 tight, with only a little daylight showing, and open up the blow reed gaps to about the thickness of the reed.

This video from Brendan Power shows you the process.

Don’t give up on a harp until you’ve tried these tweaks

Novice players make up their minds quickly about a harp. If it works well out of the box, it’s great; if it doesn’t work perfectly on the first try, it’s junk. I agree that a harp that’s badly out of tune out of the box is a bad instrument. But plenty of potentially good instruments get thrown away just because the response wasn’t perfectly suited to the player’s style.

If you have unlimited money, you can keep buying harps (at $30-$60 apiece for a mid-priced instrument) until you get one that plays the way you like out of the box. (If that’s your approach, please keep me in mind for those harps that you would otherwise throw in the garbage.) Otherwise, you can have a customizer set up your harps, or you can do a couple of simple tweaks yourself to turn a mediocre or lame harp into a solid performer. For most players, doing these tweaks is the most economical and effective way to build a collection of reliable harps that play the way you like.