C90 cassette tapes

[Radio_Dave]

Does anybody know if C90 and longer cassettes were available at the launch of the compact cassette, or did they appear at a later date?

Thanks
David

[Phil G4SPZ]

Interesting question... I don't know for definite, but I have an early Philips C90 which I believe dates back to the 1960s. The C60 had a similar sleeve design, but with red dots.

Phil

[paulsherwin]

In general most blank tapes in the cassette era were loaded with C90 tapes, the shorter tapes just having less of it. C120s really did have thinner tape, which explains the dire warnings from various manufacturers about using it. I don't know the position in the very early days of the cassette system though.

Arguably the standardisation around C90 thickness tapes allowed hifi manufacturers to optimise their designs to produce genuinely hifi performance.

[ricard]

I always thought C60 was Triple Play and C90 was Quadruple Play tape, but apparently not?

[WreckTangle]

This interview from the 50th anniversary last year suggests (page 2) that C60 and C90 were both planned from the outset.

http://www.theregister.co.uk/2013/09...lks_to_el_reg/

[batterymaker1]

So far as I remember, C60 gave you @30 minutes playing time per side, C90's @45 minutes per side. Haven't heard anything about triple or quadruple play....

[TIMTAPE]

Originally Posted by ricard

I always thought C60 was Triple Play and C90 was Quadruple Play tape, but apparently not?

I think you're right, Ricard. Standard Play, Double Play, Triple Play, Quadruple Play seem terms from a long forgotten era! There doesnt seem any reason why C90 (Quadruple play or 12.5 microns) could not have been used from the start of the cassette's life as it would have been already in use for reel to reel tape formats.

Cheers Tim

[ricard]

Sorry about the confusion, yes, when I mentioned Triple Play / Quadruple Play I was referring to the tape thicknesses of reel-to-reel tapes.

I can't remember if it was in the Swedish translation of K. E. Johansen's 'De unges båndoptagerbog' or Mogens Vincentz 'Jeg er båndamatør' (Swedish title: Bandspelare som hobby) (both from the end of the 60's/start of the 70's) that I read about the different tape thicknesses used in cassettes. That's not to say that those sources were actually correct, but it seemed plausible to me at the time. On the other hand, using QP tape for both C60 and C90 also makes sense as Paul says above.

[TIMTAPE]

Sure. I used to deal with a local supplier of cassettes who wound the tapes into the blank C Zero's as they were called, from large "pancake" reels of cassette tape. The machine was quite impressive. I'm pretty sure they always used just the one C 90 12.5mm thickness tape pancakes, I guess to save having to reload the machine with a different pancake for C 60. In practice I guess the thinner tape wouldnt have made a lot of difference to audio quality. Probably somewhat lower output, plus a more fragile tape than the thicker Triple Play.

Somewhere in my collection is a TDK C180 cassette. When I obtained it the incredibly thin tape was broken. It was quite an exercise to resplice the ends back together. Attracted to static electric charge, the bare tape ends seemed to have minds of their own!

Tim

[Radio_Dave]

Thanks for all the replies.

Well, I guess it must be safe to assume C90 tapes were around before 1070, which is what I really wanted to know.

Thanks
David

[ricard]

Originally Posted by TIMTAPE

Sure. I used to deal with a local supplier of cassettes who wound the tapes into the blank C Zero's as they were called, from large "pancake" reels of cassette tape. The machine was quite impressive. I'm pretty sure they always used just the one C 90 12.5mm thickness tape pancakes,

That would at least strongly support the OP's notion that at least C90 tapes were available from the beginning of the cassette era.

Somewhere in my collection is a TDK C180 cassette.

I remember reading about the C180 in some TDK advertising. Never seen one myself, I remember C120 being very rare too, rarely saw one and never had one myself (although that was more due to conscious choice).

[richrussell]

I had a couple of C180s at one point - loaded with a lot of copied ZX Spectrum games. They stretched and became useless after only a few dozen uses though. I suspect they might have been OK for things that were played from start to finish every time and never rewound or fast forwarded, but the tape was definitely far too thin and fragile for general use.

[Ian - G4JQT]

Yes, I remember C180 cassettes. I remember looking through Exchange and Mart (c 1971?) to find the cheapest.

I recall the ones I got had the magnetic coating in thin, close diagonal stripes. They were ok for non-hi-fi use, but the tape was too thing for repeated handling by my EL3302 Phillips cassette recorder.

Not only that, but some of the C180s I bought had the tape twisted over at various places! I remember showing them to my physics teacher who reckoned they were probably tapes cut up from unwanted computer tapes.

Ian

[Nickthedentist]

I found a load of circa 1990 TDK D-180s in a skip at a hospital in Birmingham, where they'd been used to record lectures.

I have to say that I had no problems whatsoever with them, when used in an average-quality HiFi deck.

Nick.

[emeritus]

The 1969 KJ Enterprises catalogue shows the following availablilities:

Philips: C30, C60, C90, C120;
BASF: C60, C90, C120;
EMI: C60, C90;
MC: C60, C90, C120 (possibly KJ's own brand range?).

I mostly used C120s with my original EL3302 and subsequent recorders, avoiding those that said that they were not suitable for C120s and never had any problems with breakage. However a couple of batches of Philips C120s from the early 1970s did suffer from "expansion" in that the tape seemed to get too large to fit on the space available and so jammed. This was regardless of the machine they were played on, so I had to copy them on to new cassettes.

I never had any problems getting C120 Cassettes. I mostly bought mail order from KJ, but local shops usually had them.

[mickjjo]

I have a TDK C180 which I have used many times on decent decks with no problems, I believe they were available for some years but are very rare now for obvious reasons.

Regards, Mick.

[ben]

Deviating slightly, there is definitely a clear difference in tape thickness between c60 and c90 tape in later production cassettes. In the early days they probably used the same stock, but later on this seemed to change.

[Nickthedentist]

Funny you should say that, Ben, but in my (limited) experience, I would have guessed the opposite were true!

I can distinctly remember feeling cheesed-off in the 1990s when opening a box of Maxell 45 (or was it 46?) minute cassettes to see the supply reel half full, whereas the older short-duration cassettes I had seem to have fuller reels.

And C90s were specifically banned from our late-80s ASC language labs at school because the thinner tape would tend to break. Or was that an urban myth?

Nick.

[Tony1965]

Maybe this will help

http://vintagecassettes.com/_history/history.htm

[G6Tanuki]

I did quite a bit of work in the late-1970s on using compact-cassettes for digital datalogging service on river/stream flow recorders. The Philips specs showed 30/60/90-minute audio-rating cassettes from the outset.

The C120 came later, and we had mechanical humidity/tape-stretch problems with people who used them. They really didn't appreciate a month in a box on a wet winter Welsh hillside. It was a matter of pride that I 100% recovered data from a cassette that had spent a couple of weeks submerged beneath the River Wye.

Same went for later 'Metal' and "Chrome" C30/60/90 tapes - these had bias/hysteresis-characteristics that were unnerved recording pure non-harmonically-related sinewaves at high level and I had to build a special PLL-decoder to recover the curious any-2-out-of-4-tones self-clocking [dual-Manchester] signal these things used.