A concert marimba, in two sizes
The chips above the bars switch between the two sizes a marimbist is most likely to meet. The 5-octave marimba runs from C2 to C7, 61 bars: the concert and solo instrument, and the size much of today’s solo repertoire calls for. Its bottom C is the lowest note of a cello. The 4.3-octave marimba runs from A2 to C7, 52 bars: a size many schools and students own, the same instrument without its lowest 9 bars.
Those bottom bars are the reason the two sizes exist. They are the longest pieces of rosewood on the frame, over resonators that would be more than a metre long if they hung straight, and they are a large share of what a big marimba costs. Everything a melody uses is on both, so pick the 5-octave to hear what the low end of the instrument does, and the 4.3 if that is the one you practise on at school.
Why a marimba sounds warm and a xylophone sounds bright
A marimba and a xylophone look alike — rosewood bars laid out like a piano, a tube under each one — and they sound nothing alike. The difference is carved into the underside of each bar. A marimba bar has a deep arch cut into it, and the arch is tuning: it pulls the bar’s first overtone up until it sits exactly two octaves above the note, four times its frequency, a 4:1 ratio. A xylophone bar has a shallower arch that stops at a twelfth, three times the frequency.
Then the tubes take sides. Each resonator is closed at the bottom, and a closed tube only answers its own note and the odd multiples of it — one, three, five. Under a xylophone bar the tube lifts the note and the twelfth together, which is why a xylophone cuts. Under a marimba bar the overtone is at four, an even number, so the tube leaves it alone and spends everything on the note itself. The overtone stays a colour inside a round, hollow fundamental instead of a second voice on top of it. Play the same melody here and on the online xylophone and that is most of what you hear.
The last two differences are how long and how soft. Wide, thin marimba bars over long tubes ring for seconds in the middle of the instrument where a xylophone is gone in under one, and a marimba is played with yarn-wound mallets rather than hard plastic, so each note begins with a soft thump rather than a click. That is also why a marimba sounds so different from one end to the other: the bass bars bloom and hum for three seconds, the top octave is short and woody.
Finding your way along sixty-one bars
The bars are laid out exactly as a piano keyboard is. The naturals — C D E F G A B — run in the front row nearest you, 36 of them on the 5-octave. The sharps sit in a raised back row, each one over the gap between the two naturals it lies between, with no bar between E and F or between B and C, because there is no note there. The bars shorten as they rise, and each is drawn with the cord that runs through it at the two points where the bar does not move, which is why the cord slopes across the frame.
A marimba is wider than any screen is at a size a finger can hit, so on a phone the instrument opens at middle C, where the songs are, and the strip above the bars is the whole marimba in miniature. Drag along it, or tap anywhere on it, to move to another part of the instrument; the lit window shows which bars are on screen. When a song plays, the view follows it. On a larger screen the whole instrument may fit at once and the strip simply does not appear.
Playing it like a marimbist
Tap a bar to strike it, and drag across the front row for a glissando; a bar glanced in passing sounds softer than one aimed at, as it does under a real mallet. Several fingers at once is a chord, because every bar you touch sounds, and the notes ring over one another as they do under four mallets — two in each hand, which is how most marimba music is played.
The one technique worth learning first is the roll. A struck bar cannot be held, so a marimbist sustains a note by striking it over and over with alternating mallets, fast enough that the strokes blur into one long sound. Put two fingers on the same bar and tap them in turn, as evenly as you can. On the low bars, which ring for seconds, a slow roll is enough; on the high bars, which die quickly, it has to be fast. A rolled chord — two fingers on each of two bars — is the sound most people picture when they think of a marimba.
Songs to play
Press Play a song under the instrument and pick one. The 5-octave marimba reaches 21 of the 21 public-domain songs here and the 4.3 reaches 21; they are written around middle C, the middle of the instrument and the warmest part of its range. Silent Night, Amazing Grace, Brahms’ Lullaby and Pachelbel’s Canon are the ones that suit a marimba best — slow tunes with long notes, which is where its ring does the work.
Every song has three ways in. Play plays it for you and lights each bar as it sounds. Practice lights the next bar and waits for you to hit it. Play along closes a ring onto each bar in time with the music and tells you at the end how close you were; switch on wait for me and it pauses at every note until you find it. The tab editor uses the same numbers as the bars — 1 to 7 for the scale from middle C, 1' for an octave up, 5, for an octave down — and whatever you write travels in the link you share and never reaches a server.
Playing it with a keyboard
The letters on the bars are the keys, and they start at middle C rather than at the bottom of the instrument: Q is C4, and the twenty-six letters run up the bars chromatically, sharps included, from middle C to C♯6. That is the range the songs live in, so a whole tune is under your fingers without touching the mouse. The bars below middle C and above C♯6 are for the pointer. Turn the letters off in the controls under the instrument once you no longer need them.
What the sound is made of
Nothing here is a recording. Each note is built as it is struck from what a marimba bar physically does: the note itself, the carved overtone at exactly four times its frequency, a fainter third mode near ten times that the best makers also tune on the low bars, the tube under the bar and the soft thump of a yarn mallet. The overtones fade sooner than the note, as they do in wood, and a harder tap brings them out more, so a loud note is brighter as well as louder. The tube makes the note louder and holds it; it does nothing for the overtone, because a closed tube cannot.
What is not measured is the balance between those parts — how loud each overtone is and exactly how fast it fades — because there is no single correct marimba to measure, and every instrument and every pair of mallets differs. It is a model of the physics rather than a copy of one particular instrument. Because a marimba’s pitch is carved into the wood, every note sounds at exactly its pitch every time, with none of the small random detuning some other instruments on this site use for realism.
More instruments you can play here
The online xylophone is the marimba’s bright sibling, on the same frame with a different carving. The online handpan is another struck instrument built around a long, warm ring, and the online kalimba plays the same songs on steel tines.
Frequently asked questions
What is the difference between a 4.3-octave and a 5-octave marimba?
Only the bottom. Both run up to C7; the 5-octave goes down to C2 and the 4.3-octave stops at A2, so the student size is the same instrument without its lowest 9 bars. Those bars are the most expensive part of a marimba — the longest rosewood and the longest resonators — which is why the smaller size is common in schools and the 5-octave is the concert and solo instrument. Everything a melody uses is on both.
Why does a marimba sound so warm?
Because of what is carved under each bar and what hangs below it. The deep arch on the underside tunes the bar’s first overtone two octaves above the note, a 4:1 ratio, where a xylophone’s shallower arch puts it a twelfth above. The tube under the bar is closed at the bottom, so it only reinforces the note and its odd multiples — and 4 is even — so all the tube’s help goes to the note itself. A soft yarn mallet then keeps the attack quiet. Round note, soft start, long ring: that is the warmth.
What is a marimba roll?
It is how a marimba holds a long note. A bar cannot be sustained once it is struck, so a player strikes it again and again with two mallets in alternation, fast enough that the separate strokes blur into one sound. On this page, put two fingers on the same bar and tap them in turn; on a keyboard, drum two fingers on the same letter key.
Can I play chords on the online marimba?
Yes. Every bar you touch sounds, so two, three or four fingers down at once is a chord, and the notes ring over each other the way they do under four mallets. Marimbists play four-mallet chords as a matter of routine, two mallets in each hand, and the long ring is what makes a rolled chord sound like one held sound.
What songs can I play on it?
All 21 of the 21 public-domain songs here fit the 5-octave marimba, and 21 fit the 4.3-octave, from Twinkle Twinkle Little Star to Silent Night, Amazing Grace and Pachelbel’s Canon. They are written around middle C, which is the middle of the marimba’s range and where its tone is at its best.
Is this a recording of a real marimba?
No. Each note is built as it is struck, from what a marimba bar physically does: the note, the carved overtone at exactly four times its frequency, a fainter one higher up, the tube under the bar and a soft mallet. That means the first note plays instantly and every bar is at exactly its pitch. The balance between those parts is modelled rather than measured, because every marimba and every pair of mallets sounds a little different.