[Nicklyons2]

I believe it is total coincidence that 33 + 45 = 78. The speeds were chosen, as mentioned above, as a good compromise between frequency response, needle wear, and playing time. The constituent parts of (what became) EMI did, as separate companies, differ slightly in what the figure was e.g. Columbia Graphophone 80, HMV 78.

The reasons for 33.333 & 45 is entirely due to a Beta vs VHS type war between CBS and RCA in the USA. The rise in the plastics industry around WWII had meant cheaper, lighter and most importantly, unbreakable records, could now be made from vinyl.

RCA simply wanted to replace the 78 with 7" 45s so, for example Dvorak's New World Symphony would appear on 4 sides of 45s instead of 78s. Note here that the original RCA spec for 45s only had the large centre.

CBS looked further and thought that cutting technology had improved to a point where a slightly slower speed would work and that using a bigger disc - 12" an entire symphony could be accomodated on 1 disc. The need for 'singles' being accomodated with 'kiddietunes' size discs running also at 33.333. All CBS discs were to use the same 'std' centre as 78s.

The 'battle' raged for a couple of years where each company would issue its artistes only on thier own formats and with consumers having to buy 2 record players to be able to listen to everything OR to have to plump for your favourite artist, say Frank Sinatra (CBS) and then be able only to hear artistes from that 'stable'.

Peace broke out when it was seen that this was ruining the sales of record players and records and the compromise was that large records/long duration would use CBS' std if CBS would agree to issue 'singles' to RCA's spec.