----- Original Message ----- From: Dick Spottswood >Another way to check is to look at the blank area on the disc next to the label. >You'll see a matrix number, something like 1423456. If it stands alone, it's >acoustic. If it's preceded with a circled W it's electric. Compare any Harmony with >any Columbia from the period to see--and hear--trhe difference. However, from about 1927 on, some vocal sides on Harmony were recorded electrically (i.e. Hanshaw, Vallee, etc.) but they didn't show the circled W. Whether these were recorded using the WE setup and not marked as such to avoid royalties, or whether Columbia was using Harmony to experiment with a non-WE system (which Col(UK) eventually used) has not, to my knowledge, been established. Steven C. Barr