I’ve been thinking seriously of adding another ukulele to the herd. A tenor resonator, or resophonic, like the Kala shown above. That’s the re-designed 2014 model.
I’ve played earlier models, including the 2013 version with the strings attached to a tailpiece (see photo below, left). The 2014 design (shown above) anchors the strings back into the cover plate, which I expect will be a better design; it looks cleaner, too. But I believe the biggest change is that the through-the-plate model has more tension on the biscuit (see below). And I like Kala products, too.
I really like resonator instruments and currently own a Soares resonator tenor guitar. It’s lovely; all-metal body, but a heavy beast (20lb or so)
I owned a Republic all-metal reso uke, a few years back, but it was concert scale. Interesting uke, but I didn’t keep it. I loved the look, but I don’t like concert scale as much as tenor, and I think that concert scale strings don’t put enough tension on the biscuit to make the cone work effectively. However, it gave me some ideas about improving reso uke output.
In the physics of guitars and ukuleles, the more tension on the saddle, the greater the energy passed along through the bridge to the sounding surface (top). Thus the greater the tension, the louder the sound and the greater the sustain.
A tenor uke has more string tension than a concert, and because of this it is this is generally louder and richer in tone than a shorter scale uke.
A tenor has more surface area on the top for the sound to be presented, too, and has a larger body cavity which allows for a somewhat lower range of tones than smaller instruments. On a standard, wooden ukulele, the larger surface area of the top and the (generally) larger sound hole of a tenor contribute to a wider spectrum of tones and greater volume than with a smaller instrument (the larger the hole, the lower the tones that can escape).
The top material (usually the wood) also affects how the sound is transmitted and presented, as does the body cavity size (see Helmholz resonance). The saddle and bridge materials also play pivotal roles in sound production.*
A resonator works differently (Gibson explains it well). The energy is transmitted through the biscuit (similar to the saddle and bridge but sometimes combined as one piece), then to the aluminum cone. The body cavity has less of a role in the tone (most resos don’t have large sound holes, either) and most of the sound is pushed forward from the cone – which makes it rather metallic.
The type of top wood is not as crucial to the final sound, so many resos are made of laminates (which also offer a greater structural integrity for the extra bracing required).
But ukuleles use nylon/fluorocarbon strings. These don’t have the same energy as metal (and the tension is less both because of the shorter scale and fewer strings). Aquila strings probably are the best for resos (I find them the stiffest, which means more energy is retained and translated). I tried several types on my previous reso and really didn’t like the black strings (like GHS) because they were too soft (they may be fine for other styles, however).
The biscuit needs to be made of dense material capable of transmitting (not restricting) the energy of the strings as efficiently as possible. So my first change will be to replace or upgrade the biscuit.
Reso ukes are simple designs: a single inverted cone with a biscuit on top. String energy goes through the biscuit to the cone, which vibrates it back out. Traditional biscuit material is wood, usually maple, but some are (at least in part) rosewood or ebony. Gibson tells us:
The so-called “biscuit” resonator relies on a single cone, and the biscuit — which is mounted to the base of that inverted cone – translates the energy of picking and strumming from the bridge to the biscuit to the cone. The tone produced is more even-tempered and lower than that of tri-cone models, and single cone resonators are typically less costly as well.
Stewmac, a company which sells parts and kits for building your own instrument, discussing setting up a resonator guitar, including a biscuit, and also using a “spider” bridge (you can see one here). That would be a bit finicky, I expect, but it’s intriguing. I don’t have the skill or tools to create such a bridge for a uke, but I’m curious how it might work on my tenor reso guitar.
I would look into something using denser for the biscuit, like ebony or perhaps rosewood. An alternative will be to shave down the biscuit saddle and add a slice of ebony to the top, or perhaps even a Tusq saddle. I might even try an all-plastic (or other material like brass or glass) biscuit too (something that would make the nylon strings sing a little more).
The final change will be to try metal strings. As Gibson says, the signature sound of the reso is a “hotter” than a standard, steel-string guitar, which is in turn brighter and crisper than a nylon stringed guitar.
Resonator guitars are the literal bright shiny objects of the six-string world. Once you’ve heard and seen one, it’s hard to not be mesmerized by the sizzling, crisp ring of its tone or the look of that metal pie plate in the middle of the body that all of that sound comes from.
While a standard uke cannot be strung with metal strings (you’ll tear the bridge right off), the way the resos are built I believe they can handle the additional stress.
You can hear some reso ukes compared here and judge the sound yourself:
And here’s a video just about the Kala (and some custom work done on it):
Personally, I wouldn’t mind owning the tailpiece version, but would not raise it like the video author did, because I think that lowers the angle of the string which reduces the tension on the biscuit (thus reducing the energy transmitted), and my goal would be to increase it.
But I’m told the 2014 Kalas aren’t due into Canada until August or even later. A road trip to the Twelfth Fret is in the planning to see what’s available, later, this summer.
* I’ve experimented with saddle materials like brass and glass, as well as woods, bone and synthetics (plastic) on several ukes, and replaced a few standard saddles with Tusq material. I even have some thin slices of ivory recovered from an old piano, that I will one day laminate and try. It’s amazing how much you can change the sound by just swapping saddles.
PS. You can’t really hear the speaker on this video of the 2014 NAMM show, but it’s interesting to see the wide array of ukuleles in the background: