I’m still confused
C60 = 30 minutes/side at 1 7/8 ips.
So am I: by your question!
Assuming you’re referring to audiotape cassettes, “60” usually refers to the full length, meaning each side is 30 minutes long. I have no idea how you’re differentiating between “full cassette” and “the tape”, though.
I believe the OP is asking if the tape is 60 minutes long and also double sided for a total of 120 minutes. Which might conceivably be a way of labeling a tape, but it wasn’t used that way.
They made 120 minute cassettes (60 minutes per side) but supposedly the tape was thinner than a C60 and therefor more prone to malfunction. All from my memory, from back in the day when cassette tapes were my main media. Still have hundreds of them with nothing to play them on.
TDK made a C180 and I got one, hoping to make an ginormous mix tape. While recording songs it seemed ok but the first time I fast forwarded, that was that…it was hopelessly tangled.
Someone on youtube documented it. “D” tapes weren’t that great (more consumer grade than their super avilyn or metal tapes) At the end you can see the tape is kinda transparent :dubious:
Even if you have a gentle tape transport, the thinner tapes have other drawbacks. They are subject to more extreme print-thru, where one layer transfers the signal to the adjacent layers over time, making either a pre- or post-echo.
[quote=“lobotomyboy63, post:6, topic:852856”]
Someone on youtube documented it. “D” tapes …
[/QUOTE]Wow! I am familiar with C30, C60, C90 and C120, and I vaguely remember some intermediate lengths for special applications. (There may have been a C45 or C50 for copying LPs onto.)
But I’ve never even heard of the “D” group before. I always presumed that the “C” was simply short for “cassette”, but now I have to wonder if there had ever been a “A” or “B” group. The Wikipedia article mentions many intermediate-length tapes, but they are all of the C group. Yet I can’t deny that the YouTube video shows a D180.
Perhaps you are not aware that these lengths have no special significance except to consumer packaging.
You can create any length cassette you want if you order them custom; specify the thickness and magnetic formula (standard, hi-bias, chrome, etc.) When I was using cassettes in the 1970’s, I had a few hundred wound with a 10 minute length, as this allowed for a single commercial cut on one side, using the thickest tape. I also had some wound at 50 minutes, which could store both sides of most LPs. Studios often ordered sizes that were most useful for them.
Custom duplicators wound the blanks to exactly the length they needed for a commercial music album, no more, saving pennies on each and dollars on many. They weren’t limited to 30, 60, etc. minutes.
The cost of custom winding was much less than buying shrink-wrapped units, and if you buy in bulk, you don’t have to strip off all that junk wrapping. Bulk tapes just come stacked in a box or tray.
Yes, remember when home computers loaded from tape? The Commodore Pet and C64, the TRS80 (before floppies were affordable), the Apple ][ - there was a huge market for 10-minute cassettes to hold those tapes.
The other problem with longer tapes - esp. C120 - was that the thinner tape stretched. I rarely had a tape mangle, but if you played a tape and didn’t rewind it would risk sounding all “wow” after a while. The take-up reel tried to pull the tape faster than the capstan roller instead of adjusting the take-up to the size or the winding so far, capstan limited the speed of the takeup, thus putting the takeup under tension. In rewind, there’s no capstan involved, the tape is pulled onto the other reel at low tension. This is also why it was kind to rewind with video cassettes. Leave them sitting under tension for a while and the tape would go all wonky. Plus the waste of time. Well-behaved players rewound when they hit the end - then they started making two-way players that would start playing the other track when they reached the end, and the tape never got a rewind.