French luthier Rachel Rosenkrantz plays a ukulele made using mycelium in her studio on June 21, 2023, in Providence, Rhode Island. Leave mushroom spores in a mold for a couple weeks and they鈥檒l bloom into a puffy material akin to brie, says Rosenkrantz, a sustainability-minded guitar-maker innovating with bio-materials. Once her mycelium, the root-like structure of fungus that produces mushrooms, mimics the rind of a soft-ripened cheese Rosenkrantz dehydrates it into a lightweight, biodegradable building material 鈥� in this case, a guitar-body. (Photo by ANGELA WEISS / AFP)
Providence, United States聽鈥斅燣eave mushroom spores in a mold for a couple weeks and they鈥檒l bloom into a puffy material akin to brie, says Rachel Rosenkrantz, a sustainability-minded guitar-maker innovating with biomaterials.
Once her mycelium, the root-like structure of fungus that produces mushrooms, mimics the rind of a soft-ripened cheese Rosenkrantz dehydrates it into a lightweight, biodegradable building material 鈥� in this case, the body of a guitar.
The musician trained as an industrial designer embarked on her career as a luthier 鈥� maker of string instruments 鈥� about a decade ago, and over the past several years has integrated mycelium and other biomaterials in her quest to create more environmentally friendly, plastic-free instruments.
Rosenkrantz chuckles as she delivers her brie analogy that鈥檚 also a nod to her French roots; the designer was raised in Montfermeil, an eastern suburb of Paris, and now resides near Providence where she teaches at the prestigious Rhode Island School of Design.
The basement atelier below her sunny apartment full of plants and books is home to her craft and doubles as a science lab, where she鈥檚 growing materials like kombucha leather to make banjo heads, and using fish leather to make pickguards.
鈥淚n the design world, everybody鈥檚 working with biomaterial, it鈥檚 exponential,鈥� the 42-year-old told AFP from her workshop.
鈥淚t鈥檚 not, like, a hippie solution anymore,鈥� she continued, pointing to BMW which has used flax fiber in dashboard construction, or Hermes, which has used mushroom-derived leather in their purse linings.
鈥淚t鈥檚 not a pie in the sky like just five years ago. It鈥檚 actually very tangible.鈥�
Potential
Traditionally luthiers construct guitars with woods including cedar, rosewood, mahogany and ebony, depending on the tonal qualities sought.
Wood of course is also biodegradable, but issues including overforesting have led makers like Rosenkrantz toward more sustainable options, reclaiming wood and sourcing from local woods.
鈥淒o we really need to use the same species as 400 years ago, because who really plays music like 400 years ago? A few students at Juilliard,鈥� she said, referring to the elite Manhattan conservatory.
鈥淭his is an industry where I feel because it鈥檚 craft-based, there鈥檚 a lot of 鈥榟ow things are supposed to be,'鈥� she continued, adding that woods like poplar or bamboo were long ignored but could offer new opportunities.
鈥淲hat if it鈥檚 frankensteining parts of guitars that are still good, so we don鈥檛 discard the whole instruments?鈥� Rosenkrantz said.
鈥淲e have to keep our eyes peeled and see the potential in different things.鈥�
Mushroom sound
Cue mycelium, the fungal network that lies beneath the fruit we know as mushrooms.
It鈥檚 easy to grow, easy to mold and easy to replace even if it begins to disintegrate, and can be made into both acoustic and electric instruments.
And sound-wise? Rosenkrantz鈥檚 mushroom guitar is layered and fine-tuned, and doesn鈥檛 sound just like a traditional guitar.
It鈥檚 a bit nasal 鈥� but rife with possibility.
鈥淭he idea came about when I was looking at packaging, since mushroom has been used to replace polystyrene鈥� which 鈥渋s known to be a good sound conductor, because it鈥檚 full of air,鈥� she said.
The designer found that her mycelium also conducted sound 鈥� 鈥渂ut it has a different timbre. So it doesn鈥檛 sound like something else before.鈥�
鈥淚t鈥檚 just a new sound,鈥� she continued. 鈥淚t won鈥檛 replace cedar because it鈥檚 not cedar.鈥�
She鈥檚 found the mushroom materials generally work best with electric formats: 鈥淭here鈥檚 a regular pickup, so it sounds like a normal electric guitar, and there鈥檚 also another microphone that鈥檚 in the mushroom.鈥�
鈥淪o then you can switch how much mushroom sound you want.鈥�
French luthier Rachel Rosenkrantz holds her 聯Pawtuxet聰, a guitar made using honeycomb in her studio on June 21, 2023, in Providence, Rhode Island. (Photo by ANGELA WEISS / AFP)
Help the cause
Some of Rosenkrantz鈥檚 custom-made guitars are made completely out of wood, and others integrate the more experimental biomaterials.
Given the time it takes to make a unique guitar from scratch, her instruments start at about $6,000.
But when it comes to the mushroom-based prototype, 鈥渕y dream is for a big company to say, 鈥楲et鈥檚 produce it, 50 bucks, every kid can have one,鈥� Rosenkrantz said.
鈥淪ome students cannot afford an instrument鈥� what if that could be a solution? Hello Fender, if you hear that,鈥� she said with a smile.
Much of Rosenkrantz鈥檚 work is driven by curiosity: she keeps bees, and trained them to build an art piece of a guitar by providing them the instrument鈥檚 bracing 鈥� the part 鈥渢hat guides the sound and give some stiffness to the instrument.鈥�
The bracing mimics the top bars of a hive, and 鈥渢he bees communicate through the comb at 309 hertz, which is in the guitar range,鈥� she explained. 鈥淪o we鈥檙e gonna make a honeycomb that is a natural sound diffuser.鈥�
And it worked: the bees built their comb along her structure, ate their honey over the winter, and left Rosenkrantz with a cleaned-out guitar that resonated.
The project was less about future use and more about 鈥渢he poetry of it,鈥� she said, another test to find biomaterials with acoustic qualities.
It鈥檚 exploration she hopes can help build a more sustainable future: 鈥淚鈥檓 experimenting to help the cause in some way.鈥�