Lead Belly styled himself "King of the Twelve-String Guitar," and despite his use of other instruments like the accordion, the most enduring image of Lead Belly as a performer is wielding his unusually large Stella twelve-string. This guitar had a slightly longer scale length than a standard guitar, slotted tuners, ladder bracing, and a trapeze-style tailpiece to resist bridge lifting.  Lead Belly played with finger picks much of the time, using a thumb pick to provide a walking bass line and occasionally to strum. This technique, combined with low tunings and heavy strings, gives many of his recordings a piano-like sound. Lead Belly's tuning is debated, but it seems to be a down-tuned variant of standard tuning; it is likely that he tuned his guitar strings relative to one another, so that the actual notes shifted as the strings wore. Lead Belly's playing style was popularized by Pete Seeger, who adopted the twelve-string guitar in the 1950s and released an instructional LP and book using Lead Belly as an exemplar of technique.  In some of the recordings in which Lead Belly accompanied himself, he would make an unusual type of grunt between his verses, best described as "Haah!"; "Looky Looky Yonder," "Take This Hammer," "Linin' Track" and "Julie Ann Johnson" feature this unusual vocalization. In "Take This Hammer," Lead Belly explained, "Every time the men say, 'Haah,' the hammer falls. The hammer rings, and we swing, and we sing." The "haah" sound can be heard in work chants sung by Southern railroad section workers, "gandy dancers," in which it was used to coordinate work crews as they laid and maintained tracks.

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