by Howard Fosdick © FolkFluteWorld.com
What's so fun about whistles is that you can easily switch from one size of whistle to another. All finger the same, so it's simple to change pitches and explore the different kinds of music best suited to each.
If you've learned the standard D whistle, you might be ready to explore two more kinds of whistle: the high whistles and the low whistles. We'll provide tips about each and hopefully a few insights along the way.
The High Whistles

(Cropped from Generation Music)
Penny whistles come in almost any size and key you can imagine. The photo shows the line-up of high whistles from one major manufacturer, Generation Music.
Whistles above the standard D whistle are generally considered to be the high whistles. The lowest note of the D whistle is D5. That's one note above the lowest note of the C soprano recorder.
The most common whistles above that are E♭, F, and G. Their lowest notes are E5♭, F5, and G5, respectively.

This diagram shows the scales for these keys, with their common fingering. The genius of the whistle is that you finger all whistles the same. The only difference is the different pitches of the notes that are produced.
What this means is that you can easily play in any key you like simply by playing a whistle in that key. For example, the common D whistle plays easily in the keys of D and G.
But you're in for some difficult cross-fingering if you play it in certain other keys. So instead, simply switch to a whistle suited for the key of the song in which you're playing.
The High G Whistle
Let's talk specifically about the highest pitched of all tin whistles, the high G. This photo compares it to two common high D whistles:

The high G is only about 9 inches long. You can see the reason for concern about its small size. The distance from its first fingering hole to its last is only about 3 1/4 inches. Most people can fit their fingers in that space, but if you have large hands, it could be a problem for you.
For comparison, the two D whistles are 11 and 11 1/2 inches long. The span between their first and last fingering holes is about 4 1/2 inches.
Can you fit the tiny high G in your hands? Place a ruler on a table, and try fitting your fingers into 6 imaginery fingering holes in that space. That should give you an idea of whether the high G is for you.
If the high G is too small for you, try the high F. It's about an inch longer, and it gives you about an extra inch on the fingering span. It fits almost anyone's hands.
Playing the High G
Playing the high G has its own unique feel. Beyond cramped fingering, you'll find the small tube highly responsive to your breath. This is because it takes little time for your breath to expand across the small body of the instrument.
Given its quick response to pressure changes within the tube, the high G is ideal for fast-fingered notes that could be "swallowed" by a large whistle. It articulates even the quickest notes well. Ornamentation sounds distinctly and clearly.
For this reason, the high G matches the needs of fast jigs, quick marches, and other songs that depend on rapid timing. It's the ideal instrument to show off your fast-fingered skills (assuming the tiny instrument doesn't unduly cramp your style).
One other characteristic of note. On most high G's you're able to hit the very highest notes above the 2nd octave. It depends on the instrument and the skill of the musician, but it's often true you'll get an extra note or two on the high end above the range of many lower whistles. A warning: those highest notes can be pretty piercing and unpleasant to your hearing.
Comparison to High Recorders and Ocarinas
Let's compare the high G whistle to recorders and ocarinas of similar pitch.
Recorder: The highest playable recorder is called the garklein. Its lowest note is higher than the high G whistle by an octave. It's C6 instead of the high G's G5.
The garklein's highest note is A7 (but skilled musicians with fine instruments can play higher).
Its length is shorter than the high G whistle at about 6 inches. Yet its fingering span is the exact same at 3 1/4 inches.
Learn all about the garklein in my article The Ultimate Guide to the Garklein Recorder.
Ocarinas: The highest playable ocarina is called the Soprano C. Its fundamental note is C6 instead of the high G's G5.
The high G's two octave range is greater than that of the soprano ocarina. 12 hole ocarinas typically have a 13 note range, while the 6 hole seedpod or pendant style has a range of only 10 notes.
Read a more detailed comparison of the high G to the garklein, high ocarinas, and more, in my article Exploring the Highest Pitched Flutes.
The Low Whistles
Now let's talk about the other end of the spectrum. The low whistles are usually considered as any whistle in G or lower. The lowest note of the low G whistle is G4, one octave below that of the high G whistle.
The most common low whistles are those in G, F, and D. The low D is most popular among enthusiasts.
The scales and their fingering are exactly as shown in the above fingering chart for the high whistles, except that the low whistles sound an octave lower.
With the low whistles, you have the exact opposite problem of the high G whistle. While some have trouble fitting their hands in the tiny space of the high G, with the low whistles some are unable to stretch their hands to reach all the fingering holes.
This photo tells the tale:

A low G whistle is at the bottom of the photo. You can see that the distance between the first and last fingering holes -- its fingering span -- is about 6 1/2 inches. That fits anyone's hands.
In contrast, at the top of the photo is a the typical low D whistle. Its fingering spans about 8 1/2 inches.
You'll notice that there's a third whistle in the photo, the one in the middle. That's a special "low D with close spacing" invented by Carbony Celtic Winds. Sold by Kallet Larsen Music Store and others, this is a specially-designed low D that reduces finger spacing by close to one inch. For many people, that's enough to make the difference between a playable flute and an unplayable one.
If you don't own a low D, place a ruler on a table and see if your 6 fingers can cover that 8 1/2 inch span. What you'll find is that you need to practice the piper's grib. In this grip, you splay your fingers across the lowest fingering holes, rather than using your fingertips. Here's how to do it:

(Courtesy: Whistle and Drum @Youtube)
Developing a piper's grip is essential to playing the low D regardless of your hand size. The technique works well for all the low whistles.
Beyond the piper's grip, you'll notice that the responsiveness of the low whistles is the exact opposite as that of the high whistles.
The body of a low whistle is big. So the instrument lags a tad in responding to changes in breath pressure. The result is that the whistle will poorly articulate -- or "swallow" -- fast note sequences.
Runs, cuts, flips, and rolls may not sound as crisp or distinct as they do with higher pitched whistles. Ornamentation has a lesser role in lower pitched instruments.
As a result, many feel the low whistles are best suited to slow melodic tunes, such as dirges, elegies, and slow airs. This is where their deep, soulful voices shine.
As you gain experience with the low whistles, you'll make your own judgements as to which songs are most appropriate for these instruments.
Comparison to Low Recorders and Ocarinas
Let's compare the low D tin whistle to recorders and ocarinas of similar pitch.
Tenor Recorder: The tenor recorder's lowest note is C4. That's one note below that of the low D whistle at D4.
Finger spans vary, but usually they're very close to that of the low D. My Aulos tenor's fingering span is 9 inches, while my Adler's is 8 1/2 inches.
Tenor recorder lengths vary too much to make a general statement or comparison.
Learn more about tenor recorders in my article Guide to the Tenor Recorder.
Ocarinas: The comparable ocarina is the bass ocarina. Just like the tenor recorder, its lowest note is C4 instead of the low D's D5.
Learn more about the bass ocarina in my article Bass Ocarinas.
Final Words
Part of the fun of whistling is learning about and enjoying all the different whistles available. No doubt you'll want to explore both the high and low tin whistles.
One final word of advice. I would recommend trying the low whistles only after you gain sufficient experience with the standard high D whistle. They're a bit more difficult and some prior experience will stand you in good stead as you expand your purview.
Related Articles
You may wish to read about other high flutes in my articles: