Lyres and strings
Lyres are archaeologically known from early medieval northern Europe; Sutton Hoo preserves parts of a particularly famous instrument. Reconstructed string count, tuning, and repertoire are not automatically Viking-Age facts.
Flutes and pipes
Bone flutes and the panpipe from Viking-Age York demonstrate several possibilities. Hole number and tube length constrain pitches but preserve neither compositions nor one common tonal system.
Horns and lurs
Animal horns and wooden wind instruments could produce signals and music. The wooden lur from Oseberg is an important find. Bronze-Age lurs are much older and should not simply become Viking equipment.
Rhythm and perishable material
Wood, skin, and plant fibre often decay. Absence of a drum therefore does not prove drums were unused; conversely, modern frame drums do not prove one Viking-Age standard form.
Replicas as experiment
A replica can test how material, tool marks, and construction affect sound. It becomes research when assumptions are recorded and variants compared—not when an attractive sound alone is treated as proof.