There are two models, one with 16 strings, priced at $2,999; the other with 24, priced at $3,999. (The instrument uses a combination of electric bass and guitar strings.) Various options, including a maple body or custom artwork, are available at additional cost.
Classified as a tapping instrument, the harpejji is played somewhat like a guitar, by tapping on a string to produce a note. But all 10 fingers of the player can be used in a way that is more like the approach of a keyboard player.
Small black and white patterns placed underneath the strings, and the arrangement of notes from lowest on the left to highest on the right, reinforce the keyboard influences on the instrument.
While the fundamental sound of the harpejji is guitarlike, the net effect is deeper, richer. And an accomplished player can produce an effect that suggests a lead guitar and bass together. The instrument does not sound synthesized.
"You can play chords that are hard, or even impossible, to achieve on the piano or guitar," Meeks said. "You can create all sorts of nuance — bending the note, sliding between notes, adding vibrato. There is a tone knob that lets you darken or brighten the tone. Someone who has the dexterity of playing with two hands can apply those brain circuits to this instrument. Everything else is completely new."
A distinctive aspect of the harpejji is that it's isomorphic. Scales and chords have the identical geometric shape across the board.
"Once you learn a chord position," Meeks said, "you can take that muscle memorization anywhere on the instrument."
If you buy a harpejji, you won't receive a how-to manual with your purchase.
"There are no rules," said Melani. Added Meeks: "There is no right or wrong way to play a harpejji."
Living in Nashville, Tenn., last year, the 32-year-old Melani kept in touch with Meeks by phone and email.
"Tim would send me clips of him playing the harpejji," said Melani, who now lives in Hampden. "I would hear his music getting better and better. … I don't know if we'll ever say we're virtuosos. It's still a discovery process for us."
Video demonstrations of Meeks and others are on the website of Marcodi Musical Products LLC (marcodi.com), as well as on YouTube. The latter has played a major role in spreading the word about the harpejji, Melani said; nearly half a million views have been logged. The company's fan page on Facebook has also proved effective.
Although it's hard to predict the long-range future of any newly fashioned instrument, the harpejji gives every indication of getting traction. So far, about 60 harpejjis have been sold, half of them customized models.
"What's interesting is where they're sold," Melani said. "About a third have gone overseas — Australia, Sweden, Italy."
The harpejji's use in the "127 Hours" soundtrack was a boost. "There were some great close-ups of Rahman playing it," Meeks said. "That spurred a lot of curiosity."
As the harpejji's creator sees it, the time was ripe for something different to appear on the music-making scene.
"Instruments that are out there were starting to get stale," Meeks said. "So people have been using iPad instruments, electronic, plastic-y things. But I don't think people want to see someone just pushing buttons."
Meeks considers the harpejji more organic than an electronic keyboard (or "a plastic appliance," as he calls it), and he thinks of it as having a starring role.
"We are not setting out to provide a novel-sounding instrument that is just the background of some music track," he said. "The harpejji can be the centerpiece instrument for a songwriter or a band. There's an authenticity to it, a sense of timelessness. When you hear it, it doesn't sound dated. And you know right away that it's an instrument someone has built."