3" discs are mini CDs. They were originally designed to be a sort of replacement format for the 45 single in the digital world, but they never caught on here in the States. Japan seemed to like them though, as many releases were put out over there in the 3" CD format. Today, you can even buy 3" blank discs -- they hold about 20 minutes of audio material. The problem is, you can't feed them into a player that "sucks in" the disc. You can only place them in the center depression of the player's tray, found in most home players and CD ROM drives. Car players are usually the ones that can't handle a 3" disc. It's odd, but mu car manuals have always said that they're 3" compatible, but I've never had the guts to actually try it. It's just not worth it to try it. If it got stuck in there, I'd never forgive myself.
7" is simply the size designation for a 45 or mini LP (for jukeboxes). LP's are 12" and singles are 7". There was also a 10" size that has come and gone over the years at variuos times. I have an A&M '80s-issued 10" record of Suzanne Vega's from the UK. It's a different mix of her hit "Luka".
Harry
...wondering if someone will come up with a 3" DVD, online...
7" is simply the size designation for a 45 or mini LP (for jukeboxes). LP's are 12" and singles are 7". There was also a 10" size that has come and gone over the years at variuos times. I have an A&M '80s-issued 10" record of Suzanne Vega's from the UK. It's a different mix of her hit "Luka".
Harry
...wondering if someone will come up with a 3" DVD, online...