Gibson Top Tension Banjos



1940 Gibson TB-18. Photo: Dan Loftin, courtesy Gruhn Guitars.

Although most bluegrass banjo players consider Gibson’s Mastertone banjos with one-piece flange and flat-head tone ring – such as Earl Scruggs’ Granada and Don Reno’s Style 75 – to be the ultimate banjos, those models represent only the penultimate, the next-to-last step in Gibson’s long series of banjo design improvements.

The final step came in 1937 with Styles 7, 12, and 18, better known as the “top tension” models.

The evolution of Gibson banjos spanned exactly 20 years. The company started with nothing in 1918, the year the TB (for Tenor Banjo) appeared. Gibson’s Jimmie Johnstone, a former vaudeville performer, announced to banjo players that “In a nutshell, boys, it’s in a class by itself.” Between the rim and the head, where the tone ring was supposed to be, there was nothing – no tone ring. It was indeed, as Johnstone said, in a class by itself, but not in the same class as the Vegas, Bacons, and other brands with roots in the “classic” banjo era of the late 1800s.

Gibson’s original open-back design remained through 1922 as the tenor banjo grew in popularity and Gibson fell farther behind. Gibson introduced a new family of mandolins designed by Lloyd Loar in mid 1922, and then Loar turned his attention where it was desperately needed – banjos.

In May, 1923, Gibson introduced a banjo worthy of the Style 5 designation. Loar not only added a tubular tone ring, he surmised that contact with the rim would have a deadening effect, so he raised the tone ring off the rim with a series of ball bearings. The new Gibsons also came with resonators – either a “trap door” (a hinged flat plate) or a molded Pyralin (plastic) piece that was fastened on by a screw in the center.

Loar left at the end of 1924, but Gibson continued to improve banjo designs. In early ’25, a new ball-bearing style (probably Loar’s design) had the ball bearings resting on springs. Also, the tone ring was altered so the head angled downward just before it met the tension hoop. (Although this second version of the ball-bearing ring gave the head an arched effect, the ring described today as “archtop” didn’t appear until 1927.) At the same time, Gibson switched to a modern-style cupped resonator, attached to a flange by four thumb screws.

By 1927, Gibson introduced a new tone ring featuring a U-shaped cross-sectional shape, with the outer arm of the U slightly shorter than the inner arm. This gave the head a beveled or angled border and became known as the “archtop” tone ring. The archtop remained the standard spec on the Mastertone models introduced before 1937, from Style 3 up through the All American, all the way to World War II.

The archtop tone ring was an excellent design, but Gibson pressed on with new designs. In 1929, the tube that had served as a tension hook anchor in the pre-flange era was done away with. The old style would be called “tube and plate” and the new version would be known simply as “one-piece.”

At about the same time, Gibson began fitting some banjos with a new type of tone ring, with the U cross-sectional shape inverted. The upper curve of the inverted-U was offset so that the head only contacted the tone ring at its outermost point. The bevel at the edge of the head was gone, and this new design became known as the “flat-head” tone ring. It continued to evolve, too, from a lightweight “low-profile” style to a higher profile and finally to a heavier weight (about three pounds).

The last version of the flat-head tone ring – the high-profile, heavyweight – is the one preferred by today’s players, and it came as standard equipment only on the new banjo models of 1937 – Styles 7, 12 and 18. The calling card of these new models was not the tone ring, however, but their “top-tension” adjustment capability. Before the advent of plastic, banjo heads were made of animal hide. In a humid atmosphere, the player had to tighten the tension on a hide head or it would be too spongy, and in dry conditions the head would contract and would be in danger of tearing if the tension was not loosened. To adjust the hooks (there were 24 of them), the resonator had to be removed. If the head could be adjusted without removing the resonator, the player could save some time, and that’s what the “top tension” models offered. The player still had to remove the armrest (one screw) to get to the tension hooks that were located under the armrest, but all in all, top tension adjustment seemed like a better idea. (In fact, the Ludwig company had introduced top-tension models in the late 1920s). The only problem with the design was the threaded flange, which was made of pot metal. Many surviving examples have washers and nuts anchoring the tension hooks where the flange threads have been stripped.

Several other new features came on the top-tension models. Where Gibson resonators since 1925 had been laminated and pressed into an arched shape, the new models had solid-wood resonators that were carved into an arched shape on the outside but were flat on the inside. The frets were guitar-size, which were larger than the standard banjo frets. And the fingerboards were radiused.

The top tensions came in three different levels of ornamentation and materials. Style 7 had a maple resonator and neck with rosewood fingerboard, slotted bow-tie inlays on the fingerboard and headstock, and nickel-plated hardware. Style 12 had a walnut resonator and neck with large Art Deco-style inlays and chrome-plated hardware. Style 18 had a maple resonator and neck, the same Art Deco inlays as the 12 and engraved gold-plated hardware.

Gibson was confident enough in the top-tension models that the company quit making all the Mastertone models except the new Style 75 (essentially a continuation of Style 3) in 1938. From 1937 through 1941, Gibson shipped 85 top-tensions with tenor necks, 28 plectrums and 28 five-strings, for a total of 141. The standard-adjustment Mastertone, Style 75, was less expensive and sold only slightly better: 104 TB-75s, 6 PB-75s and 55 RB-75s for a total of 165. Although the domination of tenors (TBs) ended after the war, the pre-war Gibson Mastertone tenors are still in high demand today because the neck can easily be replaced with a five-string neck.

In the post-war years, banjo players religiously followed Earl Scruggs and Don Reno, and the top-tensions were largely forgotten until Bill Keith played a Style 12 (an original tenor with a conversion neck) in Bill Monroe’s Blue Grass Boys. His banjo had a smoother tone with more sustain than those played by the banjo icons, and it was perfectly suited for his innovative “chromatic” style. Not surprisingly, the top-tension models have found a home today in the music of such modern stylists as Bela Fleck and Noam Pikelny (known for his work with John Cowan and
Chris Thile).

This article originally appeared in VG‘s May ’07 issue. All copyrights are by the author and Vintage Guitar magazine. Unauthorized replication or use is strictly prohibited.

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