mwilliams@mahler.DEC (Mike Williams 229-6258 LTN1-2/B17) (04/03/85)
Subjects: Cassette durability query Audio Amateur query For 6 or so years, I have been using TDK SA cassettes in my BIC T3. A good number of these were also used in a car deck (Jensen RE505?) which I no longer have. I have been experiencing regular failures of my older/more-frequently- listened-to tapes. There are two failure modes. One is that over time, the tape does not wind uniformly (w.r.t. position) on the internal spools. That is, the edge of the tape which is at radius r from the spool is not in the same plane as the edge of the tape which is at radius R. Obviously, as this progresses, the tape edges contact the case increasing the effort required to pull the tape out causing tape stretching or tripping the mechanical end of tape detector. The other failure mode is not as gradual. The tape does a 90 deg barrel roll inserting its edge into the seam of the case. From this key starting point, a whole host of wonderful things can happen, the worst of which is that a crisp seam forms along the length of the tape. This failure occurs most commonly in tapes that are in early-stage type 2 failures. I suspect that the fault is in the media, more than the tape drive. I never have problems with new tapes, and this only occurs in my cassettes that have many hours of play time, or that are among the older ones. Given that I'd rather stick a needle in my eye than onto one of my records (I tape the first time I play), and that the record cleaning ceremony I go through would put many semiconductor foundries to shame, I would like to get as many miles out of a tape as possible. My questions to the net are: 1. Would anyone care to venture an EDUCATED guess as to what is happening? 2. Is this a common problem with the TDK SA? 3. Are my expectations for tape longevity too high? 4. Is there a tape made that has a reputation for longevity AND acoustic quality? (What's Maxell's rep?) 5. My principal suspicion is tape case warpage. Does this vary with case construction (glued vs. screwed vs. both)? If so, which has the best chances of outliving the others? Anticipating some responses: I do plan to get into CD, but a lot of what's in my record library won't be available for a long time, if at all. These problems have spanned several tape alignments (which were done at different shops). I've also seen references to The Audio Amateur in various discussions. Would somebody please post some relevant subscription info - $$$, address, typical content. Thanks in advance, Mike Williams -=- -=- -=- -=- -=- -=- -=- -=- -=- -=- -=- -=- -=- -=- -=- -=- -=- -=- -=- ARPA: mwilliams%mahler.DEC@decwrl.ARPA UUCP: ...!decwrl!dec-rhea!dec-mahler!mwilliams USENET: decwrl!rhea!mahler!mwilliams@BERKELEY US MAIL: Advanced VAX Development Digital Equipment Corporation Mailstop LTN1-2/B17 Littleton, MA 01046 VAX is a trademark of Digital Equipment Corporation "Bees are generated from decomposed veal" - Sir Isidore of Seville, Spanish prelate and scholar, 7th Century
aww@cybvax0.UUCP (Arch Williams) (04/06/85)
> Subjects: Cassette durability query > Audio Amateur query > > I have been experiencing regular failures of my older/more-frequently- > listened-to tapes. There are two failure modes. One is that over time, the > tape does not wind uniformly (w.r.t. position) on the internal spools. > > The other failure mode is not as gradual. The tape does a 90 deg barrel roll > inserting its edge into the seam of the case. > > 1. Would anyone care to venture an EDUCATED guess as to what is > happening? I'm not familiar with that model BIC but my Hitachi D-850 had the exact same symptoms that you describe above. If you're not concerned about warranty violation, remove the cover from the deck and check the rewind spindle (the hub on the left with ridges that rewinds the tape (yeah, I know, there's probably a special word for it)). There is usually a small braking mechanism that rubs against the back of the spindle during play and properly tensions the tape as it goes through the first capstan. The brake itself is usually a small, thin piece of metal with a patch of felt attached to it. In my case the felt had fallen off. It's incredible how much damage a 10 cent part can inflict upon a tape collection. For a quick check, take the door off the deck (these usually slide off for access to the heads), play a tape, and wait for the bugger to try and eat it. When the sound becomes garbled, usually the first warning, put your finger on the front of the spindle and press lightly. This will cause enough friction to get the tape tensioned again. If the tape begins to play well again then that is the problem. I still don't know why the new tapes worked fine (although, in the end they too were eaten halfway through the first recording) and for a while cleaning the capstans would help. So far the deck hasn't curled a tape for six months so the fix seems to have worked. > 4. Is there a tape made that has a reputation for longevity AND > acoustic quality? (What's Maxell's rep?) I have almost always used Maxell UD XL II/IIS tapes (except when the deck first aquired it's appetite and I tried feeding it different brands) and have found them to be of good quality and durability. I do not, however, use the same recorded tape for the car and the home stereo. The car tapes usually suffer from heat/moisture exposure and sound rather bad when played on the home system. It's worth making two copies. > 5. My principal suspicion is tape case warpage. Does this vary > with case construction (glued vs. screwed vs. both)? If so, > which has the best chances of outliving the others? I heard a rumor (i.e. take it for what it's worth) that the companies that use screws to join the shells together do so for product appeal (looks sturdy) and not for any practical reasons. Hope this info helps. Arch Williams
dca@edison.UUCP (David C. Albrecht) (04/11/85)
> > > 5. My principal suspicion is tape case warpage. Does this vary > > with case construction (glued vs. screwed vs. both)? If so, > > which has the best chances of outliving the others? > > > I heard a rumor (i.e. take it for what it's worth) that the companies > that use screws to join the shells together do so for product appeal (looks > sturdy) and not for any practical reasons. > > Hope this info helps. > > Arch Williams I have used Memorex, TDK SA, TDK SA-X, TDK MA, DENON, and Sony UCSX and have had the least trouble with the TDKs finding that they rarely fail. I think that Memorex spread the rumor about sonic welded cassettes being just as good as screwed cassettes and if their tapes are any indication I say stick with the ones with screws. All the Memorex that I bought sounds like you have a drum set in your deck when fast forwarding or rewinding and last about 6 months before jamming. Both the DENON and Sony seemed more prone to car environment problems with the Sony especially bad because if any tape is extended to outside the cassette mechanism it turns into christmas ribbon and is very difficult to get back into the shell. I have heard good things about Maxell but have been happy with TDK so I haven't bothered. David Albrecht General Electric
roy@hpmtla.UUCP (roy) (04/16/85)
Why not simply return the old tapes and re-tape on new ones?
I believe then TDK-SA series has an unconditional lifetime
guarantee. I use Maxell UDXL, and have utilized this weakly
publicized guarantee on many occasion. TDK users have told
me the SA series does the same. So... you have to re-tape,
but so what?
!hpfcla!hplvla!hpmtla!roycrandell@ut-sally.UUCP (Jim Crandell) (04/16/85)
> > I heard a rumor (i.e. take it for what it's worth) that the companies > > that use screws to join the shells together do so for product appeal (looks > > sturdy) and not for any practical reasons. > > I have used Memorex, TDK SA, TDK SA-X, TDK MA, DENON, and Sony UCSX > and have had the least trouble with the TDKs finding that they rarely > fail. I think that Memorex spread the rumor about sonic welded cassettes > being just as good as screwed cassettes and if their tapes are any indication > I say stick with the ones with screws. All the Memorex that I bought sounds > like you have a drum set in your deck when fast forwarding or rewinding and > last about 6 months before jamming. My experience with both TDK and Memorex is virtually identical. Even so, I think that there's a little more to the rumor than first appears. Take a trip to your neighborhood K-Mart (or local equivalent) and you'll probably find (if you look -- not that I blame you if you don't) some really cheap but frequently snazzy-looking cassettes made in Hong Kong, Korea, Monaco or some other out-of-the way place. These things nearly always have screw- fastened shells, and their quality is frankly pathetic. (Don't under any circumstances use one of these in a good deck! What they can do to a transport shouldn't happen to a Craig.) It's entirely conceivable that they use screws for cosmetic effect, although I've always suspected that the approach just seems like good business in an economy where a few hundred slaves with screwdrivers can be acquired with a much lower capital investment (and possibly even operated at lower cost) than exotic sonic welding equipment. -- Jim Crandell, C. S. Dept., The University of Texas at Austin {ihnp4,seismo,ctvax}!ut-sally!crandell
ron@brl-tgr.ARPA (Ron Natalie <ron>) (04/17/85)
> My experience with both TDK and Memorex is virtually identical.
I don't know about the welded vrs. screw argument, but I've found
the quality control on Memorex Audio and Video cassettes to be somewhat
lacking,
-Ronherbie@watdcsu.UUCP (Herb Chong [DCS]) (04/17/85)
Someone wrote: >> > I heard a rumor (i.e. take it for what it's worth) that the companies >> > that use screws to join the shells together do so for product appeal (looks >> > sturdy) and not for any practical reasons. <deleted comments by other people> the real reasons are that 1) it is easier to control amount of pressure in precison molded cassette halves (TDK quotes 10 microns for each half) by torquing the screws instead of sonic welding. with bubble slipsheets the force on the actual tape can be known just from the force required to advance the screwdrivers (which are totally automated gun-types capable of doing about 2 cassettes per second). 2) it is practical for repair broken cassettes wich are screwed together, but then the optimum pressure is no longer present unless you have a screwdriver with a torque gauge and you know what it is. it is far more expensive to use screws than sonic welding, so no manufacturer is going to use it unless there is another overwhelming reason to. most do because of the requirements to maintain consistent and standard tape skew between tapes and batches of tapes. Herb Chong... I'm user-friendly -- I don't byte, I nybble.... UUCP: {decvax|utzoo|ihnp4|allegra|clyde}!watmath!water!watdcsu!herbie CSNET: herbie%watdcsu@waterloo.csnet ARPA: herbie%watdcsu%waterloo.csnet@csnet-relay.arpa NETNORTH, BITNET, EARN: herbie@watdcs, herbie@watdcsu
crandell@ut-sally.UUCP (Jim Crandell) (04/18/85)
> > > My experience with both TDK and Memorex is virtually identical. > > I don't know about the welded vrs. screw argument, but I've found > the quality control on Memorex Audio and Video cassettes to be somewhat > lacking, > > -Ron Right. Please try rereading the quoted posting and putting the line in context. Thanks. -- Jim Crandell, C. S. Dept., The University of Texas at Austin {ihnp4,seismo,ctvax}!ut-sally!crandell