Stroh violins were invented to direct string sound into early recording horns

Evidence

Recording technology was not very sensitive at the beginning of the twentieth century. Singers and brass instrument players could cut a record directly by playing loudly into the mouth of a horn that had a diaphragm and a needle at its throat, but the more-or-less omnidirectional sound from stringed instruments made recording difficult. The original purpose of the Stroh violin was to concentrate the sound toward the recording device horn. — Eric J. Heller, Why You Hear What You Hear- An…, 1859

Categorization

• XREF: Connects to the book’s recurring theme of how horn loading and source loading shape instruments — earlier chapters on the gramophone and horn acoustics. — connects to: A diaphragm loading the bridge drives the Stroh violin’s horn; All stringed instruments share a source-modifier acoustic model
• corroborated: 2 independent passages support this claim — Eric J. Heller, Why You Hear What You Hear- An…, 1859

Broader Connections

• A diaphragm loading the bridge drives the Stroh violin’s horn #expands (0.90)
• All stringed instruments share a source-modifier acoustic model #exemplifies (0.75)