'hearpan' - Plummer describes the harp as 'the national instrument of our forefathers' and a skilled harpist was eagerly sought in early Northumbria, for instance by Cuthbert, abbot of Wearmouth-Jarrow, quia citharam habeo, et artificem non habeo, 'because I have the harp, but not the ability'. It's interesting how fashions changed; just a century later we find Alcuin making his famous pronouncement, quid Hinieldus cum Christo ('what has Ingeld to do with Christ?'), bemoaning that entertainment in the monastic refectory was more often the harp than the sermons of church fathers. See, by way of illustration, the harp at Sutton Hoo.
It's interesting to speculate how OE poetry might have been delivered orally. Pope has suggested a harp for accompaniement, and this might have been used tonally or (perhaps more plausible) rhythmically. It seems likely that vernacular poetry was delivered swiftly, since a canon of the Council of Clofestoh (747) advised that priests should not sing the divine office hurriedly, garbling it 'like poetry' (poetarum modo). We should be unwilling to attribute to oral poetry the 'heightened sense of dignity' that Tolkein found evidence of 'a mind lofty and thoughtful' in Beowulf and from which Sisam extrapolated 'a rate of delivery which the dignified style suggests'.