On Friday 16 June 2006 10.25, Lou Judson wrote:
Curiosity quibble - isn't the groove on a 45 midway between microgroove and 78 size? Is there a specific name for it, or is it really considered microgroove like Lps? I see a distinct difference, visually... or is that just the larger excursion?
I think it depends on the 45...for EPs they cut really fine, low-modulation
grooves, but I noticed when I was a kid in the 70s that more recent stereo
45s had grooves that were not as fine as LPs, but not nearly so coarse as
mono 45 grooves from the 1950s. Pick up a 1950s pressing of an average R&B
or rock'n'roll record and you'll see the grooves are larger than modern
grooves, plus the pitch is wider and the modulation is almost as wide as some