Talk:Cassette tape

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A typical portable desktop cassette recorder from RadioShack.

Track layout

"the two stereo tracks lie adjacent to each other rather than a 1/3 and 2/4 arrangement. " -- could someone explain this for the layperson? -- Tarquin

I think it means that the tape is laid out like this:

1111111
2222222
3333333
4444444
<---> direction of tape

rather than:

1111111
3333333
2222222
4444444

Where 1 and 2 are the stereo channels of side one, and 3 and 4 are the stereo channels of side two. How to put that into simple language without taking up half a page is a different matter, however... --Camembert

The second diagram is wrong. Compact Cassette recorded the side A stereo on track 1 and 2 in the first diagram (and side B on tracks 3 and 4. Reel-to-reel recorders, on the other hand recorded the side A stereo on tracks 1 and 3 in the first diagram (and side B on tracks 2 and 4). This meant that although the stereo recording could be played back on 4-track mono machines (provided it permitted replay from both sections of the head), they could not be played back on 2-track mono or stereo machines. Mono 2-track recordings could be played back on mono 4-track machines (and stereo machines if the machine would play from one track only - as most did).

Interesting. But I don't understand how this change is advantageous. Bastie 12:21, 12 October 2005 (UTC)

I think it means that it's easier to build cheap monophonic players because they can get by with only two heads. One head can read both the left and right tracks in one direction and the other head can read the left and write tracks in the other direction. That makes their mechanics simpler and cheaper. I'm not an engineer, but that's how it was explained to me once. If anyone has a better explanation, I'd love to hear it. Joe 13:46, 12 October 2005 (UTC)

This is a good diagram of the types of R2R recording. Bastie 13:15, 23 October 2005 (UTC)

This is how the channels are located. By having the channels this way, makes it possible for mono playes to play stereo recordings (in mono) and vice versa. atmo 23:52, 9 February 2006 (CET)

We should have our own diagrams of this; they should be fairly simple to do. I was thinking of doing some of my own when I get off my lazy ass, but if someone else wants to do them first, no problem with me. Fourohfour 15:21, 10 February 2006 (UTC)

I read somewhere that a Stereo compact audio cassette, actually has five tracks... Tracks 1, 2, 4, and 5 have audio on them. Track 3 is silent... Side one is made up of Tracks 1, 2, and half of Track 3. Side Two consists of The Second Half of Track 3, plus Tracks 4 and 5. The Silent Track in the Center is there to help prevent crosstalk between the two sides.§ —The preceding unsigned comment was added by Garr1984 (talk • contribs).

That's interesting, but can you find a reliable source for it? Fourohfour 11:37, 9 March 2007 (UTC)

It was in some Handyman's encyclopedia, in a section discussing how to repair 8 Track and Cassette Tapes. Garr1984 04:09, 22 March 2007 (UTC)§

Discussion continued at New info on track & tape width dated 22 March, 2007 --Blainster 20:48, 26 March 2007 (UTC)

Article title

Is 'compact audio cassette' a meaningful term? The official name is "Compact Cassette", and it's usually referred to as an "audio cassette" or simply "cassette" nowadays... so where did this hybrid come from? Has it ever been used except as a result of this article?

I'm not convinced that it's worth changing the title of the article now (too much hassle with links), but if this is simply a neologism, wouldn't it be preferable to discourage its use elsewhere?

Fourohfour 10:14, 26 September 2005 (UTC)

I'd strongly favor "Compact Cassette" too, because it's the official name, and this would keep it in line with Compact Disc, and Digital Compact Cassette, the name of both of which derives from Compact Cassette. But it might be a pain with all the links.  ProhibitOnions  ^(T) 09:41, 14 May 2006 (UTC)

That's the only reason I didn't change it long ago... I'm sure that with the proper tools and/or admin powers it would be fairly simple, but I haven't looked into it yet. Fourohfour 20:38, 14 May 2006 (UTC)

Being an admin, it was no problem, so I did move it. Quite a lot of articles linked to "Compact Cassette" anyway, but I fixed all the redirect pages, of which there were many; less than half of articles linked to the previous article title "Compact audio cassette" so it was a problem that needed fixing anyway. I'll fix as many article links as I can but might look into getting a bot to do it instead.  ProhibitOnions  ^(T) 13:20, 23 May 2006 (UTC)

Great stuff, nice to see you changed it anyway! Fourohfour 12:26, 10 June 2006 (UTC)

"Tape" was the most common referal in my corner of the globe (Central United States).

Image of cassette types

Anyone else feel that this since the shells for the different tape-types aren't standardised, and what you can see of the tape inside looks the same, it doesn't actually add to the point it's meant to be illustrating?

OTOH, it's a fairly good technical shot (much better than the slightly-out-of-focus, non-colour-corrected, flash-reflections-showing, clutter-in-the-background stuff that sometimes appears on Wikipedia). Perhaps it should simply be rebadged as a general shot? Perhaps I'm nitpicking...

Fourohfour 10:03, 26 September 2005 (UTC)

I agree — while an excellent photo, it doesn't help to explain the differences between types of cassette. Laypersons might think that the differing appearances of the shells have something to do with the different tape types, which is not the case at all. Slicing 04:40, 4 December 2005 (UTC)

I've changed the caption; we now have an illustration of the differences between the types elsewhere anyway. Fourohfour 16:00, 4 December 2005 (UTC)

I added a second image of a higher quality cassette, A TDK MA-X to compliment the existing phito of a low end tape, the TDK D series. Teamgoon 23:28, 19 August 2006 (UTC)

I wouldnt mind seeing a timeline of casette types (as images), as they varied significantly over time. I've no images to offer though :( Tabby 16:01, 9 September 2007 (UTC)

8-tracks vs. the audio cassette

There should be some mention of the 8-track in here. I'd like to know how the 8-track ever got off the ground if, in addition to an inferior design, it was launched five years after the aduio casette. -Litefantastic 23:58, 12 March 2006 (UTC)

Bear in mind that cassettes were not originally intended for musical use, and that until the late 1960s their audio quality was (apparently) pretty ropey. I assume that the 8-track was marketed for musical use from the beginning. Whether it was actually better than the early cassettes, I don't know (doubly so because they never took off in Europe and I've never heard one). Fourohfour 00:05, 13 March 2006 (UTC)

The 8-track cartridge was introduced in 1964, only about a year after the cassette. But at the time the cassette was not much good for music, while the 8-track's 3.75 ips speed gave it a more tolerable high frequency response. Since 8-track tape was 1/4 inch wide, the track width was about the same as a 4-track stereo cassette. From 1964 until 1972 or possibly later, if you wanted to play music other than radio in your car, the only factory option was 8-track tape. The 8-track would play endlessly while the cassettes you had to flip over before auto-reverse came out. The two drawbacks to 8-track were its larger size (about 4x cassette), and its proclivity to tape wow due to friction in the tape layers which had to slip past each other in the endless loop. --Blainster 10:27, 13 March 2006 (UTC)

In addition to the above, cassettes were pretty fragile back in the early days - 8 tracks were much more robust and could be kicked around the floor of a truck without too much harm coming to them, and they were easy to slam into the deck without any problem. Ideal for mobile use. In car cassettes were at first very delicate little precious things that would throw a hissy fit at the slightest provocation, spilling the tape all over their prissy little innards! In-car units in the early days also cut silly corners like putting the tape in endways to save space but then not having any spigot for the supply reel and thus no back-tension on it. This was recipe for tape spillage. Also the fiddlyness of cassettes was considered too dangerous for in-car use compared to the chunky 8-track that could be loaded without taking your eyes off the road. Basically, cassetees simply weren't seriously considered as an in-car music format until the mid to late 70s. Graham 10:58, 13 March 2006 (UTC)

Lindos links

Please do not add commercial links (or links to your own private websites) to Wikipedia. Wikipedia is not a vehicle for advertising or a mere collection of external links. You are, however, encouraged to add content instead of links to the encyclopedia. See the welcome page to learn more. Thanks. AlistairMcMillan 21:52, 1 April 2006 (UTC)

I am very surprised and puzzled by this comment. Firstly, I have added no links to my own private website (I do not own or control Lindos Electronics). Secondly, Wikipedia is full of external links to company sites, often of poor quality. Lindos is a very high profile company in the area of audio measurements, and the articles on its site are very pertinent to many Wikipedia topics. The test sheet database is a novel public resource, built by users, rather like Wikipedia, and hence of great interest to those reading audio topics and to Wikipedians. My personal interest has always been in improving the understanding of audio quality and measurement, and that is my role now, through my own business Lindos Developments, which does not sell anything but has income from IP rights. Perhaps you should have a go at the IPod page. That's pure product advertising for one manufacturer!!

Retrieved from "http://en.wikipedia.org/wiki/User_talk:Lindosland"

Branchlist

I've noticed that in addition to the "Compact Cassette" logo, the branchlist was added, and now keeps getting moved around. The problem is that with the branchlist, contents table, cassette image and logo image, there isn't enough room for all of them near the start without the layout suffering. Frankly, the way the intro looks just now isn't good, and I wish we could just settle on something that is a bit more presentable than this. Fourohfour 12:28, 2 April 2006 (UTC)

Mixed up article!

This article doesnt know whether its about the cassete tape or cassette recorders. Which is it? It cant be both and needs to be split!--Light current 01:08, 6 May 2006 (UTC)

Who says it needs to be split? Surely the two are mutually necessary? Of course, the general concepts of audio tape and audio tape recorders probably warrant separate articles, but for the Compact Cassette.... nah. Fourohfour 20:38, 6 May 2006 (UTC)

I don't think a split is appropriate. You can't really meaningfully discuss the development of the cassette in total isolation from the machines because improvements in both were necessary for the medium's success. There is an article at cassette deck which serves the need for focusing specifically on the machines, but I think this article as it stands has a good balance. Graham 13:20, 7 May 2006 (UTC)

Third world

From the article:

Although its use in the West has declined as a result of more advanced technologies, it remains widespread, and is still the dominant medium for listening to music in many third world countries.

Really? I don't think so. Where does the author got this information from? —The preceding unsigned comment was added by 200.153.183.111 (talk • contribs) 12:31, 14 May 2006 (UTC)

I've seen this discussed in several articles and TV programmes. As I can't specifically remember where this was however, I did a quick search of the web and found back up for it here:-

And outside of the music stores of the West, cassettes do continue to survive as a music format, in countries such as Afghanistan and India. In some markets, performers record directly onto cassette. [..] Turkey still sells 88 million cassettes a year, India 80 million, and that cassettes account for 50% of sales in these countries. In Saudi Arabia, it is 70%. (Source: BBC Article, June 2005)

and here

In Africa, India, and parts of the Middle-East, the cassette is still king. (Source: seemagazine.com article, 2004)

Hope this clears things up. Fourohfour 17:25, 10 June 2006 (UTC)

Mix Tape

What, no mention of mixtapes? That was one of the biggest things about cassettes was that you could make a mix tape for your girlfriend. Ah, nostalgia. —The preceding unsigned comment was added by 204.87.87.170 (talk • contribs) 08:21, 16 May 2006 (UTC)

Ummm, in the "See also" there is Mix tape. Graham 04:21, 17 May 2006 (UTC)

Mixtapes were not exclusive to cassettes. It has been done on reel to reel in the 50's & 60's. When I was a kid in the late 70's & early 80's, I would make mix tapes on 8 Track to play on the portables in the cars. And people now do it on CD-R. So mixtapes have no exclusivity to cassette. Teamgoon 12:29, 19 August 2006 (UTC)

True in theory, but not how it was in practice. For 99+% of the population, the cassette was for a long time the only accessible way to make music compilations. Tabby 15:59, 9 September 2007 (UTC)

"Actual size" image

In reference to the thumbnail of the Compact Cassette, Blainster's edit summary says he put it back to being large (300px) so that it's close to actual size. I've no wish to get into an edit war, so I've not made it smaller again, but I do think it wrecks the page for people with lower screen resolutions, by consuming potentially half of the available content space. (Some people still use 640x480!) This lack of accessibility is a shame. I'd see your point though, if it were possible to make things look actual size; that might be useful. But it's not what you've done here by specifying a number of pixels. The tape looks about half actual size on my widescreen laptop, for example, because it has very small pixels. If it looks actual size to you, that's a factor of your monitor. I'd suggest taking a new photo of a tape alongside a ruler or reference object. – Kieran T ^{(talk | contribs)} 00:48, 11 June 2006 (UTC)

A ruler only demonstrates something that should already have been explained verbally; e.g. if we're told that a tape is 12cm wide, having a ruler "show" this adds nothing. Why? If someone can't visualise 12cm, then showing it on a ruler isn't that helpful, unless the ruler represents an object of well-known size. And we often don't get to see the whole thing anyway.

If it's really necessary to have measurements on the photograph, then (e.g.) double-ended arrows with lengths marked for width, height and depth would be less intrusive. Fourohfour 22:18, 15 June 2006 (UTC)

I don't entirely agree, but I wasn't trying to be an advocate of rulers, I was merely hoping to be constructive rather than just negative. But it's moot anyway — Blainster revisited the page and decided to specify a smaller thumbnail. – Kieran T ^{(talk | contribs)} 22:26, 15 June 2006 (UTC)

Tape lengths

I wasn't aware that C46 was ever a common or popular cassette tape length, as the article suggests. C60, C90 and C120 have always been the standard lengths, but quite a few manufacturers produced "odd" sizes from time to time. AdorableRuffian 09:46, 21 September 2006 (UTC)

C46 was very common for use with data storage and indie recording artists. I'll try to find a cite for that. I do know that a lot of punk tapes from the 70s and 80s are on C46. Kafziel 11:32, 21 September 2006 (UTC)

I recall TDK C46s from the 1980s (they always had the widest range). They were sold reasonably widely, but I still reckon their sales were dwarfed by C60s and C90s. Nor do I know if anyone else sold them. Common? It's all relative. As for data, wasn't that those short C12/C15 cassettes? Fourohfour 01:13, 6 November 2006 (UTC)

The point of the C46 was that it was exactly the length of a typical LP. Drutt 12:05, 31 August 2007 (UTC)

C45 & C96 are missing on that list. Maybe it would be helpful to split the list into 3 sections: most common (60,90), fairly common (45,46,74,120) and others also in use (all sorts) Tabby 14:57, 9 September 2007 (UTC)

In the audiobooks application, where recordings may span several hours, cassettes also have the advantage of holding up to 120 minutes of material whereas the average CD holds less than 80.[12]

I'm not clear how cassette's 60 mins a side beats CD's 80. CDs take up less space and cost less per minute than tapes - though this wasnt always the case of course. Tabby 16:20, 9 September 2007 (UTC)

µS?

In the section on "Cassette Types" it talks about 120 and 70 µS playback equalization -- does this mean microsecond? If so, isn't the recongnized SI symbol for second a lowercase s, which means it should say µs? It might be better to just say "microsecond" anyway for those who don't know what μS means.

I would change it myself but i want to be 100% sure that μS means microsecond.

"1 microsecond (1 μs) – cycle time for frequency 1 MHz, radio wavelength 300 m (AM mediumwave band)" --Microsecond

--Robert 19:41, 22 October 2006 (UTC)

Yes it means microsecond, and so should have the lower case 's'. I've always found this nomenclature a bit odd really - because what it's really saying is that the playback equalization curves have a rolloff point at a certain frequency, corresponding to those values - 14,285Hz for 70µs, and 8333Hz for 120µs. Graham 03:15, 26 October 2006 (UTC)

Oh, thank you for that. I was at a total loss as to what a µs had to do with equalization -- especially since the equalization article didn't mention µs at all! Do you think it would be okay to put Hz in the main article instead of µs? --Mdwyer 04:08, 27 October 2006 (UTC)

For some reason, this is the terminology used in the industry, so we should probably stick to it. It might be worth adding a footnote explaining the situation (putting it in the main text would probably bloat things out too much). Fourohfour 01:20, 6 November 2006 (UTC)

OK, this one has always been a mystery, even to me. And converting 120 or 70 "microseconds" to Hertz taking them as period durations would give 8.33 KHz and 14.285 KHz accordingly, which means that if those were AC bias frequencies they should be pretty audible and far from "high frequency" standards (they would double if they were taken to mean semi-periods, though). EpiVictor. Then again, tape bias works exactly by mixing a high-frequency AC signal to the recorded signal...only that those AC bias frequencies appear too low compared to the intended frequency response (20HZ-16KHz for Chrome tape, somewhat worse for Ferric tapes). Maybe then the "S" refers to some other kind of unit like e.g. magnetic induction? EpiVictor 14:55, 6 November 2006 (UTC)

This is a very tardy reply to your question, but I saw it here and thought I'd better correct your confusion. The frequencies corresponding to 70µs and 120µs are indeed those quoted, but this is the rolloff frequency of the fixed audio band preemphasis and deemphasis that is applied to these tapes, and has nothing to do with the AC bias signal. The bias typically runs up at around 100kHz and while that also varies in AMPLITUDE with tape type (the bias switch selects both the AC bias amplitude and the audio de-emphasis rolloff) its frequency is pretty much irrelevant, as long as it's way above the audible range. 203.87.74.230 (talk) 05:42, 8 January 2008 (UTC) (formerly GRAHAMUK)

big hole

The history section jumps straight from around the mid 70s to after the 90s, skipping the years when cassettes were at their peak entirely. That's a pretty big problem. Night Gyr (talk/Oy) 23:36, 24 October 2006 (UTC)

Do you have anything in particular you'd like to see? The article does make mention of the walkman, of boomboxes, and of using casettes to get punk rock behind the Iron Curtain. I'm not sure there were any major technological developments for cassettes themselves during the 80s; innovations in fidelity from the 70s just continued to become more mainstream and edge out records. If you can give me an idea of what it's missing, I'll be happy to do the research and add the specifics. Kafziel ^Talk 15:09, 25 October 2006 (UTC)

I'd like to see some kind of mention of those years within the chronological history, even if it's just "incremental technical improvments, sales peaked at XXX, Cds were introduced Y, overtook cassettes Z." basically a more fleshed out arc of rise and fall instead of skipping their peak. The article sort of has this information now, but the temporal leap goes from the pre-heyday to the present, and then looks back to the downfall. Night Gyr (talk/Oy) 03:02, 26 October 2006 (UTC)

I'm sorry, I really want to help but I don't see the temporal leap you're talking about. The history section does talk about the 80s, right in between the 70s and the 90s. It starts with the paragraph that says "During the 1980s" and takes up more than half of the "Introduction of music cassettes" section. The "Decline" section gives specific sales numbers and dates demonstrating the move toward CDs. The history of the CD is only relevant to the article as it pertains to cassettes; in other words, the year CDs were invented doesn't matter, only the year they began to outsell tapes (which is in the article).

I guess I'm just not seeing what's missing, but of course feel free to add any information you think it needs. Kafziel ^Talk 15:15, 26 October 2006 (UTC)

Ah, the thing that threw me off is that the last sentence before the 90s talks about 70s india, so it actually goes back before it goes forward. Night Gyr (talk/Oy) 15:59, 26 October 2006 (UTC)

Oh, okay. When I wrote it I thought it would be best to keep all the "social impact" stuff together. If you think it would be better to split it up for the sake of chronology, that's cool, too. Kafziel ^Talk 17:29, 26 October 2006 (UTC)

I think splitting the social stuff isn't so bad because as people read it they can see "ok here it impacted india, ok here it impacted the soviet union" and pick up on the theme as the events are mentioned. Night Gyr (talk/Oy) 18:05, 26 October 2006 (UTC)

Vinyl record deck????=

I have followed hi-fi and stereo technology sinec the 1950's and never before saw the term "vinyl record deck" Is this the British term for a phonograph turntable? "vinyl record deck" gets only 237 Google hits, several of them from this article or mirrors of it, while "turntable" gets over 10,000,000. I will therefore change the term in the article to the more familiar one. Edison 02:33, 27 October 2006 (UTC)

I agree. Vinyl record deck is absurd. Kafziel ^Talk 02:37, 27 October 2006 (UTC)

ah, the memories..

i haven't noticed how further away from the cassette we've been now with all those hardisks and cds. i guess it's our own "gramophone" memories..

Well, I like them too, but I'm not really into music so it doesn't make a difference. And with hard disks and MP3s it's easy to delete the songs you no longer like. I actually deleted all of my songs, because I prefer watching a movie instead.

tape recorder for calculator

I remember that texas instruments Ti-74 could save data files on cassettes, via a tape recorder.

contradiction

This text, in "Decline" is apparently contradictory:

Cassettes are typically more rugged and resistant to dust, heat and shocks than most digital media (especially CDs). [...] However, cassettes generally have poor resistance to the excessive levels of heat encountered in parked cars during the summertime.

This ought to be resolved. –Joke 03:58, 27 October 2006 (UTC)

8-Track adaptors

Several companies produced adaptors to use Compact Cassettes in 8-Track players. The simplest were no bigger than an 8-Track tape and only the take-up spool was driven. A lever engaged the drive, sometimes with a further position for fast forward. A slightly better version offered rewind and kept back tension on the supply spool. Another version added an AA cell to power an amplifier. The ultimate version was bulkier, with a flip up lid for the cassette and from what I remember from when they were new, it didn't rely on the 8-Track's capstan for driving the cassette, using either its own battery or a 12 volt cord plugged into the vehicle's cigar lighter socket. Among the companies who sold these were Kraco, Craig and Audiovox. Radio Shack had their own Realistic or Optimus brand which may have simply been one of the others relabled for Radio Shack. —The preceding unsigned comment was added by 67.136.145.226 (talk • contribs) .

Tape complexity

A Compact Cassette can vary widely in the number of individual parts it is assembled from, depending on its price.

Low end, cheap.

• 2 snap together shell halves, with open slots to view the tape remaining/used.
• 1 tape without leaders.
• 2 spools.
• 2 tape retainers to snap into spools.
• 1 magnetic shield.
• 1 pressure pad.
• 1 pressure pad spring.
• 2 guide rollers.

12 individual parts.

The cheapest of the cheap don't have guide rollers, but that's rare. These low-end tapes usually do not have liners between the tape and shell.

High-end, expensive

• 2 screw together shell halves.
• 2 clear windows. (All clear, single piece shell halves omit the seperate windows.)
• 2 anti-friction liners. (These can be anything from thin sheets of plastic to various slick polymers with ribs to reduce contact area and even graphite mixed into the plastic.)
• 5 screws.
• 1 tape.
• 2 leaders.
• 2 spools.
• 2 tape retainers to snap into spools.
• 1 magnetic shield.
• 1 pressure pad.
• 1 pressure pad spring.
• 2 guide rollers.
• 2 steel guide roller pins.

25 parts.

Some of the higher priced cassettes included sliding write protect notch covers, but those would interfere with the sensing notches for Type II and higher tapes. Those would increase the parts count to 27.

From 10 to 27 individual parts go into a Compact Cassette. This doesn't take into consideration contents lables, as most commercially recorded cassetts have their contents printed directly onto the shell halves.

That's always made me wonder how music companies could sell them for less than a CD which is produced rapidly on fully automated machinery, is essentially a single piece'*', and involves zero per-piece recording time, whereas the Compact Cassette must be high speed recorded on multiple transport machines after being assembled from its multiple parts.

'*'CD parts

• 1 polycarbonate disc
• 1 sputtered on aluminum coating
• 1 layer of laquer
• 1 layer of printed lable, so that's only 4 "parts" for the nitpickers. :)

Regarding the cassette vs. CD cost; my guess is that in the early days, this *may* have reflected setup costs (including new production plants, CD mastering costs and equipment). This would have been done from scratch *and* the equipment would have been relatively new and expensive then. Plus, the relatively small numbers of CDs sold in the early days would have been quite small, meaning they had to absorb more of the above costs per unit.

In contrast, audio cassettes were an established technology, the equipment would already have been in place, and the duplication equipment price would have been driven down by development over time and economies of scale.

Of course, there came a point where CDs *were* genuinely cheaper to produce than cassettes; AOL sure as heck weren't paying £12/$20 a go for those discs they gave away in magazines. Yet the manufacturers were still charging the same high prices they'd said would come down. Why?

Simple answer; record companies are greedy *******s who'll charge as much as they can get away with. (Casual CD piracy wasn't an issue until burners got cheap in the late 1990s). Plus, ripoff retailers like Virgin/HMV hadn't yet faced competition from online stores such as Amazon, and since the public was used to paying more for CDs (although the reason for them being expensive had long gone), they got away with charging stupid prices for them.

(N.B. This answer is original research/personal opinion, and doesn't belong in article itself). Fourohfour 18:57, 27 October 2006 (UTC)

Yet another variation on the Compact Cassette was having miniature flanged reels instead of the flangeless spools. These tapes were limited in capacity due to the inability to use more than half the available space inside for tape. The advantage to this was reducing tape edge wear to no more than a full sized reel-to-reel tape deck would have. —The preceding unsigned comment was added by 67.136.145.226 (talk • contribs) .

That was indeed one advantage, but the main advantage is that cassettes of this kind looked pretty darned cool. I have a couple of them still (TEAC made quite a few of them, and there's a picture of one on that page), but I think mine are all C46, a slightly inconvenient size. C60s were available, but for the reason you mention they used the thinner C90 tape to make it fit on the spool. If they had C90s, they may even have been C120 thickness, with the attendant reliability issues. ProhibitOnions ^(T) 18:44, 7 January 2007 (UTC)

FWIW absence of tape rollers was standard on cassette singles in the 90s.

Linerless cassettes were rare, and never fully reliable. Liners were an important part of basic cassette function, and flat sheet types were in the minority and not as reliable. All decent quality liners were 3d. This is easily understood if you appreciate why liners were used. Tabby 15:55, 9 September 2007 (UTC)

Opposite side recording

The audio is recorded on the opposite side from the lable. Ie, when you're looking at the Side A lable of a cassette, the one or two tracks with that program are on the side of the tape opposite the lable. Very infrequently a commercially recorded tape gets put in a mass copier backwards, then makes it past quality checking to be sold with the contents lable and program on the same physical side, but 'backwards' when played. —The preceding unsigned comment was added by 67.136.145.226 (talk • contribs) .

Auto Reverse

There's no mention of auto reverse technology in this article, which is especially odd given the image of that high-end Nakamichi deck that physically flips the tape over to change sides instead of simply reversing the tape direction. The methods that reversed the tape direction used either tension based sensing (which could break weak leader to tape bonds or pull the tape loose from the spools) or optical sensing that ran the tape between a light source (visible or infrared) and a detector so the tape could be reversed the instant the clear leader passed the sensor. Optical sensing decks have tension detecting as a backup for tapes with opaque or no leaders. To use an input adaptor (for CD or MP3 players etc) in an optical sensing auto reverse deck, without a reverse disabling switch, requires covering part of the opening on the side toward the transport, otherwise the deck will just sit there flipping the direction back and forth. (Like the GM factory deck in my 1986 Cadillac Cimarron!)—The preceding unsigned comment was added by 67.136.145.226 (talk • contribs) .

I just changed the intro to clarify that you play the two sides of the cassette by either physically turning it over OR reversing the direction of the tape. 193.113.57.161 11:55, 27 October 2006 (UTC)

There were head alignment issues with autoreverse, and it remained unpopular on audiophile decks. It was more popular on mid range kit. Tabby 15:51, 9 September 2007 (UTC)

Playing video games off cassettes

I can remember playing video games off a cassette drive on either a Commodore 64 or an Atari. This would seem to be a significant phenomenon not mentioned in the article. - } (talk • contribs) 07:29, 27 October 2006 (UTC)

It's in the article. There's even a picture of the Commodore tape drive. Kafziel ^Talk 12:33, 27 October 2006 (UTC)

Yes, it says "data", not "video games". They weren't just used for tape backups, you know! ;) / Samsara

Video games are data. CD-ROM can be used for games, too, but it doesn't specify that in the Compact Disc article. It just says "data". Data can take a million forms; we can't list every possible application. Kafziel ^Talk 16:08, 27 October 2006 (UTC)

Maybe the latest addition to the section makes the video game aspect a little clearer? Kafziel ^Talk 16:12, 27 October 2006 (UTC)

Yes, it's a start. Still looks a bit lopsided with so much of the article dedicated to usage for audio data. (Btw, I do know what data is ;) ). - Samsara (talk • contribs) 21:12, 27 October 2006 (UTC)

The only perhaps noteworthy addition would be specifying that "double format" cassette tape games existed, e.g. the same tape contained both the ZX Spectrum and Amstrad CPC version of a game, or Commodore 64 coupled with either of the others. Also, some of those "cassette games", when not in "double format", included a normal and a turbo loading version, with the user choosing between the two as needed. Plus, there were some copy protection schemes implemented on audio cassettes which were -allegedly- hard or impossible to reproduce just by duplicating the tapes. EpiVictor 10:41, 7 November 2006 (UTC)

Congratulations

...on making it to featured article status, and thanks in particular to those who pushed for this and worked to tidy up the few remaining rough edges. Fourohfour 11:14, 27 October 2006 (UTC)

Thanks! Kafziel ^Talk 12:35, 27 October 2006 (UTC)

Good job people! --Anas Salloum 13:25, 27 October 2006 (UTC)

In car audio

First, nice article - deserving of FA.

I would comment that the popularity of the cassette in the UK/Europe was considerably driven by car radio makers building in a cassette player. 8-track players were not so popular as the space in European cars meant you could have a 8track player or a radio, instead of the combined radio/cassette player. Also, prerecorded cassettes were (likely as a result) more widely available, and the potential of easily hometaping your records onto cassette meant you could take "your" music with you - and if your hometaped cassette failed you could always make another copy.

A further note; in the UK beat boxes were known as "Ghetto Blasters", referring to Black American culture. LessHeard vanU 12:42, 27 October 2006 (UTC)

Radio-broadcasted programmes for 8-bit computers

Back in the days when 8-bit computers dominated the market we had a radio programme over here (Poland) once in a while (I was quite young then so it's hard to recollect, I'm thinking it was once a week or two), which focused on computer software. The speaker would talk of news and, as this was permitted due to lack of copyright laws and because the transmission was audio, 'play' on the radio a computer programme, which could be recorded on a tape, and then afterwards run on the computer. I wanted to add this to the article, however I've got no sources to back this up except that I remember it. I'll try to find something if anyone's interested. --Ouro 13:03, 27 October 2006 (UTC)

When BBC -branded microcomputers were common in the UK in the early 1980s, late-night radio broadcasts of BBC BASIC programmes would be produced for computer users to tape on cassette and then run them on their computers. It was billed as "a Takeaway from the Chip Shop".Zagubov 13:12, 27 October 2006 (UTC)

We've had this in the second half of the eighties till the beginning of the nineties. I think the broadcasted programmes were usually for the Atari, because we've made frequent use of this medium and I've had (damn it, I still have!) an Atari 65XE. The programme was broadcast midday and was called Radiokomputer. --Ouro 13:19, 27 October 2006 (UTC)

Who calls them "Compact Cassettes?"??

I would support a move/rename to something that reflects English usage more, like cassette or audio cassette.--Sonjaaa 18:35, 27 October 2006 (UTC)

It's a brand name. The design is public domain, but the trademark name still stands, just like Compact Disc. I can't remember the last time I called a CD a "Compact Disc", but it's still the correct title for the article. Kafziel ^Talk 18:42, 27 October 2006 (UTC)

All of the alternative names redirect here, and "cassette" is hardly more common than "audio tape" or any of the others so choosing any of them over the others would be totally arbitrary, Compact Cassette is the best title for this. --W.marsh 20:13, 27 October 2006 (UTC)

So for consistency should Football (soccer) be renamed to Association football then?--Sonjaaa 23:13, 6 November 2006 (UTC)

I don't see the parallel. Kafziel ^Talk 00:40, 7 November 2006 (UTC)

Errr, yes it should. I should really go and do that. Chris Cunningham 09:46, 7 November 2006 (UTC)

Another thing; there's more than one type of "audio cassette" (DAT, DCC...) out there. Okay, most people use it to mean the standard Compact Cassette, but I still think it's a bad title.

We can't call it "cassette", because there are many other common uses of that term.

And the article's original title "Compact audio cassette" was just inaccurate and pointless; neither a commonly-used title, nor a proper brand name.

Fourohfour 11:26, 8 November 2006 (UTC)

What about cassette tape? —Preceding unsigned comment added by 24.149.203.252 (talk) 08:29, 15 September 2007 (UTC)

Vandalism

Looking through the recent edit history there seems to be a lot of vandalism corrections. Perhaps this article should be locked. Kc4 18:58, 27 October 2006 (UTC)

This happens with every front page article. There's no need for protection unless an edit war starts or the vandalism gets to the point where it can't be handled. Gdo01 19:02, 27 October 2006 (UTC)

oh ok, I guess I have jsut revealed my inexpierience with featured articles with this Kc4 05:36, 28 October 2006 (UTC)

(edit conflict) Ah, if only. See my fifth rule. Kafziel ^Talk 19:04, 27 October 2006 (UTC)

I thought all Featured Articles were locked for 24 hours. --Munchkinguy 21:33, 27 October 2006 (UTC)

From the sounds of things it definatley sounds like needed policy, it is too bad that some people get something out of pety vandalism, after it is not like there is any political gain from the Compact Cassette article. Kc4 05:36, 28 October 2006 (UTC)

Reason for disappearance of chromium dioxide and ferrichrome

I seem to remember that cobalt-energised tapes, rebranded as “high-bias” took over from chromium dioxide and ferrichrome ones because while none of them could be recorded on properly by older ferric oxide-compatible machines, chromium dioxide was a more abrasive material which shortened the usable head life of older players so they couldn't even be played on them. Anybody remember if this was the case? Zagubov 21:41, 29 October 2006 (UTC)

Never heard of an abrasion problem, and Chromium dioxide tapes are still manufactured or at least they are still available for sale, without having to step into a dedicated audiophile shop (like it might be the case with Metal tapes). Ferrichrome was another issue though, and I have never seen a tape esplicitly labelled as "ferrichrome". Maybe some high-quality ferric tapes are actually ferrichrome and are somewhat compatible with most standard cassette recorders and players, but I never heard of abrasion problems with those either. EpiVictor 16:58, 5 November 2006 (UTC)

Maybe the abrasiveness was an urban myth. Although I thought I read about it in the hifi press I never experimented with a chromium dioxide till I bought a deck that could handle them. I only ever owned one cassette which was ferrichrome (made by BASF I think). just for curiosity’s sake; old cassette decks used to have three settings with FeCr as the middle one. The idea was that it had a top chrome layer over the ferric oxide.and they must have been expensive to make. Never saw them again after the 70s and I wasn’t able to detect better sound quality over other tapes.Zagubov 20:40, 6 November 2006 (UTC)

My apologies; I hadn't realised this was covered by another article already Chromium(IV) oxide.Zagubov 20:46, 6 November 2006 (UTC)

Head abrasion was a common problem, and caused lots of decks to be scrapped. As the head surface wore down, the head gap widened, and hf response fell. Tabby 15:48, 9 September 2007 (UTC)

Prerecorded cassettes

If some proof is needed, I can provide photographic evidence that (new) prerecorded cassettes are still made and sold, at least where I live (Greece). Now, since my region has a mixed Greek/Turkish population, most of these prerecorded cassettes come from Turkey, usually featuring Greek or Turkish artists but international ones as well, such as Shakira. So no, at least from my experience prerecorded tapes aren' a thing of the past nor a third-world phenomenon yet. EpiVictor 17:03, 5 November 2006 (UTC)

"Repair" section

Isn't this in danger of turning into a "how-to" (which Wikipedia *isn't* meant to be)? Fourohfour 13:26, 30 December 2006 (UTC)

Cassette single: Third opinion from interested parties

Hi there, Would be grateful if anyone interested could please take a brief look at this dispute on cassette singles, and provide your opinion. Thanks. Fourohfour 17:38, 8 February 2007 (UTC)

New info on track & tape width

I went looking for data on tracks and found more than anticipated. The region between tracks left unrecorded is referred to as a guard band, not a track or silent track, plus there is a guard band between each of the 4 tracks of the stereo cassette. This archived specification page lists the track width as 24 mils (0.61 mm), a number that is closely corroborated in a discussion group as 23.5 mils. But the most interesting thing is that I kept running across the tape width as being 3.81 mm, rather than the 3.18 mm that we agreed on as a result of the archived discussion of this page in December 2005. One of the editors at that time claimed that he had actually measured the width with a vernier caliper, getting a result "a fraction under 3.18 mm", which just happens to be 1/8 inch. I deferred to him without making my own measurement. It now seems that our assumption of good faith in accepting his original research was unwarranted, especially since the journal of the Audio Engineering Society says the width is 3.81 mm. So I dug out my best steel straight edge scale, with engraved 1/64th inch increments, and several cassettes all measured between 9 and 10 64ths, about 3.7 mm, clearly closer to 3.81 than 3.18 mm. With these results in hand, I will boldly change the numbers to conform to reality rather than our previous reasonable assumptions. --Blainster 19:58, 22 March 2007 (UTC)

Well, the figure may be correct, but as 1/8 of an inch is 3.175 mm (i.e. nowhere near 3.81 mm), I've tagged the claim as dubious. I'm also unclear if the reference given (name=IEC) refers to the previous two sentences, or not (as it isn't an online resource); if the latter, then we need the reference for the figures included in the text. Fourohfour 17:48, 26 March 2007 (UTC)

I agree that this is not crystal clear, but the evidence is cumulative. Don't take my word on measuring the tape, please check it yourself. The Google search on "cassette + width + 3.18" gives 18,000 hits while "cassette + width + 3.81" gives 12,000 hits. But the 3.81 number has more reputable sites such as IEEE, AES, and ANSI. Isn't it strange that the standards sites all reference 3.81 and not 3.18? A little thought shows that the highly specialized tape manufacturing business doesn't allow non-standard tape widths to be economically feasible. Note that this DC100 article mentions "modified Philips digital tape cassette used in the HP 9830A" and "Unlike the DC300 [1/4 inch QIC tape], the DC100 used narrower tape (measuring 0.150 inches, although known as eighth-inch tape)". So the DCC (Digital Compact Cassette and digital data cassettes use the same tape width as compact cassette, which is 0.150 inch or 3.81 mm. --Blainster 20:48, 26 March 2007 (UTC)

This site: Magnetic Tape Story is in German, but if you scroll down to 1963 in the history you will see the tape width of the cassette given as 3.81 mm. Note that in Germany they didn't have to deal with metric to English conversions. The development date is given here as August, 1963 in Hasselt, Belgium with one of the engineers named Haarler. The first model was called the EL-300 (in the U.S. it was the Norelco Carry-Corder 150). This AES abstract gives the name of another engineer as L.F. Ottens (elsewhere called Lou Ottens). --Blainster 11:36, 27 March 2007 (UTC)

Finally, this may be what you are looking for: The TDK spec sheet for their standard "Dynamic" audio cassettes, showing that the tape width is indeed 3.81 mm. --Blainster 12:11, 27 March 2007 (UTC)

I should have been clearer. What I meant was that if the real width really is 3.81mm, then where did the 1/8" figure come from? Even allowing for approximation, 3.81mm is between 1/6" and 1/7". Even allowing for being "nominally" 1/8", who claimed this in the first place? I've removed it; if there's any mention of 1/8" in some plausible literature, please feel free to put it back though. Fourohfour 17:39, 29 March 2007 (UTC)

Where to put info on the old RCA tape cartridge?

In 1958 RCA introduced a 1/4-inch tape cartridge that was obviously a forerunner of the cassette. It looked remarkably like a cassette... just much larger; even larger than the elcasette. It had about a six inch by nine inch footprint. Here's a picture: http://www.richardhess.com/tape/rca_cart.jpg

And here's an archived RCA promo film: http://www.archive.org/details/Revoluti1958 (the stuff on the tape cartridge starts about halfway through at 7:58)

They ran at 3.75 ips and used four interleaved stereo tracks, just like open-reel 1/4 inch stereo. They had very little market success. I saw them used in high school language labs in the late 60s.

Should info on this go in the Compact Cassette article, perhaps under an "earlier attempts" section head? It certainly shouldn't be in the four-track cartridge article, as it's radically different even though it is a "four-track cartridge." Jeh 10:17, 1 April 2007 (UTC)

...speaking of which, the Elcasette should probably be mentioned here too, in the "successors" section with a link to the main article. Jeh 20:09, 1 April 2007 (UTC)

To be honest, the article is already as long as it should be, and covers the title subject quite well. What you request sounds interesting and notable, but it probably deserves a separate article. Fourohfour 18:51, 16 April 2007 (UTC)

It certainly does. AFAIK, it was referred to by RCA as the "RCA (Victor) tape cartridge" with no specific format trademark. I might therefore start RCA tape cartridge if someone else doesn't beat me to it! ProhibitOnions ^(T) 16:37, 30 April 2007 (UTC)

Memory size

How many bytes a cassete tape can store? Is this usefull information to compare with disketes IMHO —The preceding unsigned comment was added by 201.79.50.163 (talk) 21:07, 25 April 2007 (UTC).

I suspect that figuring out the answer to this would be borderline original research. Fourohfour 14:11, 29 April 2007 (UTC)

There are two possible answers to that: maximum theoretical and maximum practical. Maximum theoretical can be based on assumptions about frequency response and SNR ratio. Assuming a rather poor 50 SNR ratio and a 10 KHz bandwidth, the Shannon–Hartley theorem says the maximum bit rate should be 166 kbit/sec for a single track (20 KB/sec). Using standard stereo tracks would nearly double that etc. Of course that's the maximum density achievable on a given quality of tape with the "best" modulation method available, and the simple FSK used in 80s homecomputers was nowhere near that efficient, however dedicated data streamers came quite close, assuming the tape quality could be considered constant and reliable. For example of practical systems using non-trivial modulation methods and multiple tracks, some figures have already been provided in the following posts. EpiVictor 15:55, 5 May 2007 (UTC)

From the article: "A rate of 2000-bit/s equates to a capacity of around 660 kilobytes per side of a 90-minute tape." ie. roughly comparable to a 1.2MB 5.25 floppy dish, but much slower of course. Drutt 00:45, 30 April 2007 (UTC)

Special purpose data cassettes were able to store 60 MB by 1990 (ex.: Maynard Maynstream 60M, Maxell CS-600HD) and later up to 150 MB (Maxell CS-600XD). --Blainster 08:30, 30 April 2007 (UTC)

Were they based on the Compact Cassette format though? Fourohfour 14:37, 30 April 2007 (UTC)

Yes, shell and tape were physically compatible. The only visible difference was a square notch (rather than an indentation) out of the center along the write protect edge. They were commonly known as "streaming cassette tape" or "cassette streamers". I just checked an old manual. The tapes could store 27 MB on 4 linear tracks, 60 MB on 9 tracks, and 150 MB on 18 tracks. Data transfer rate was 86 kB/sec. Recording density was 10 kB/in for 20/60 MB and 12.5 kB/in for 150 MB. They used the DMA channel and a PC bus card for data transfer on MSDOS PCs. Maybe this stuff needs its own article. This format is not mentioned on Template:Magnetic tape data formats. --Blainster 16:20, 30 April 2007 (UTC)

Oh yeah; I know what you're talking about now. My father had some old (used) ones that I think they were throwing out at his work; used them (as normal cassettes) for recording computer programs onto. Fourohfour 12:41, 5 May 2007 (UTC)

I used a few of those special data ones as ordinary music cassettes, and wasnt very impressed with them. Fancy cases but cheap tape. Just a way to justify more profit I suspect, the prices they sold for in the 80s were excessive. But at least they were much better than domestic grade C10s, which were not good quality IMLE of them.

When assessing data capacity for domestic cassette use, bear in mind that IRL dropouts occur with tape, and with no error correction implemented the data has to maintain integrity through every dropout, so one can rely on no more than 5kHz or so before the implementation starts becoming too unreliable. Even 5kHz does not make for a consistently reliable system.

FWIW there were a small number of computer-only decks (not to be confused with the many standard analog decks sold as computer decks) which used digital recording of a basic sort. The analogue signal was simply comparatored and clipped into a digital stream that was recorded onto the tape at a high saturation level. No erase head was then needed. A comparator was used on the playback signal. Reliability was improved. The system was 100% compatible with ordinary analogue recorders.

Maybe a separate article for computer data on cassettes is the best option. Tabby 15:45, 9 September 2007 (UTC)

MZ 80K

The Sharp MZ 80K was the first Sharp computer using the Z80 chip and was the first with an integral cassette deck. Circa 1978/9. It was sold in the UK. —The preceding unsigned comment was added by 84.13.75.152 (talk • contribs).

I put a heading on this comment, as it seems to have nothing to do with what preceded it. Was it meant to go in the article itself? Fourohfour 16:54, 7 May 2007 (UTC)

Article length

In the section on the RCA Tape Cartridge, Fourohfour wrote:

To be honest, the article is already as long as it should be, and covers the title subject quite well. What you request sounds interesting and notable, but it probably deserves a separate article. Fourohfour 18:51, 16 April 2007 (UTC)

The article length could be made a lot more manageable by pushing most of the section on recorders and players into the separate article that already exists for that material. As it is, people seem to keep adding details here that really should be there... IMHO of course. Jeh

You're probably right, but it's not something I can be bothered doing today :)

I still think that the RCA Tape cart would warrant its own article regardless, though. Fourohfour 16:54, 2 June 2007 (UTC)

NR?

My '92 Chrysler LeBaron has a button on its tape deck to turn something called 'NR' on and off (It doesn't seem to make a difference in tonality). I just bought some new Maxell tapes, and they have little checkboxes on the track-list sleeve that says 'NR O-YES O-NO'. But I can't find anything in here about what NR is or what it possibly could be or stand for. Anyone have any information? PolarisSLBM 11:13, 24 May 2007 (UTC)

NR stands for noise reduction. It is probably Dolby B noise reduction (or a clone of it); if the player has the "Dolby System" logo somewhere on it then this is what it will be. Some players use a different system called Dynamic Noise Reduction that does not require cassettes to be pre-encoded; it essentially turns down the high-end volume during quiet passages to reduce the perception of tape (or FM) hiss. If your player has a "DNR" logo on it somewhere, this is what it is, and if it does, please take a picture of it and add it to the Dynamic Noise Reduction article - the logo, or at least an image of a player equipped with it, is sorely needed. Regards, ProhibitOnions ^(T) 12:40, 24 May 2007 (UTC)

I just looked at it. It doesn't say DNR or have a Dolby logo. PolarisSLBM 16:01, 7 June 2007 (UTC)

"NR" usually meant a clone of DNR. You can tell DNR from dolby by switching it in during recording: DNR has no effect on recording, its a basic play-only NR system.

However if its a '92 deck its bound to be dolby, not DNR. Marking this as NR was not usual.

Tabby 15:32, 9 September 2007 (UTC)

I need some help....

I am doing a project for school and I am having a very hard time finding the information I need, I need to know....

1.) How many different 8 track tapes have been released?

2.) How many different Compact Cassette tapes have been released?

I can guarantee you now that *no-one* will *ever* know the true answer to that one, even approximately. Aside from deciding what to count as a "proper" release, there have been countless releases in many countries all over the world, including third world markets, etc etc. At best someone might be able to estimate to within an order of magnitude of the correct figure, but anyone who says that they "know" this for a fact is lying. Fourohfour 11:10, 6 June 2007 (UTC)

3.) How many different reel to real tapes have been released?

If anybody cna help me that would be great, thank you, respond or email me at shawnmort@hotmail.com —The preceding unsigned comment was added by Patriotfan012 (talk • contribs).

New material... but article getting too long. Move elsewhere?

I reverted this change, not because I thought it was bad, but because it went into too much depth in an article that is already really as long as it should be.

Here is the material:-

Among home computers that primarily used data cassettes for storage in the late 1970s were Commodore PET (early models of which had a cassette drive built-in), TRS-80 and Apple II Plus, until the introduction of floppy disc drives and hard drives in the early 1980s made cassettes virtually obsolete for those who could afford such drives, such as professional users and computer enthusiasts. However, for many consumers it was a different story. Floppy drives in the very early 1980s were extremely expensive, sometimes costing more than the home computer itself, and floppy disk software also tended to carry a much higher price tag than cassette software. For both these reasons, many consumers in the 1980s (a time when many bought their first ever computer) opted for cassette-based computers and cassette software, even when disk-based software was available. Cassette based home computers were very popular in the UK and the rest of Europe, whose 8-bit software market was dominated during the 1980s by cassette games for the Sinclair ZX Spectrum, Commodore 64 and Amstrad CPC. Due to the large userbase which cassette-based computers built up in the 1980s, commercial cassette games continued to be released in Europe until the early 1990s.

Can anyone think what we should do with this?

Fourohfour 14:33, 4 August 2007 (UTC)

bandwith ?

I find almost nowhere information about bandwith. I find between 15 and 20khz for high end cassette (and recorder) model. But, what about typical cassette and typical recorder ?

15 and 20kHz are very optimistic figures. The player might have been able to handle such fs, but putting 20kHz through the whole rec + play cycle would be a feat indeed. The few spec sheets I saw for recorders were in the region of 8kHz bandwidth for ferric, and over 10 for chrome. (Not certain but I think bandwidth also varied with recording level.)

Tabby 15:30, 9 September 2007 (UTC)

Tape Types

I'm fairly sure I bought new ferrichrome tapes in the early 90s, Realistic brand from Tandy, reduced as end of line, so I think sales of FeCr went on at least as far as then. They certainly weren't popular though.

Now my memory's a bit vague on this one, can anyone cofirm/deny this? IIRC there were real metal tapes (silver tape) and metal bias tapes (black tape). I rarely bought type IV, but I think (and am not certain) the latter version quickly took over from the former, since it was a cheaper mfr process, probably doped cheaper material types. In practice the high price tags on all type 4s ensured they saw few sales.

Finally in the later days of cassettes there were chrome EQ ferric tapes. These were prerec ferric tapes designed to be played on the chrome setting, giving reduced noise. Such tapes could also be produced by copying a chrome tape played at 120us onto a ferric tape. It was a workable trick, but tended to cause some confusion in practice. Many decks had 120/70 selector switches controlled by the cassette shell, making manual switching difficult. Tabby 16:31, 9 September 2007 (UTC)

FWIW there were also some cassettes with head cleaning leaders, ISTR scotch or 3M Tabby 16:33, 9 September 2007 (UTC)

Intellectual property aspects

I notice that Compact Cassette has what looks like a trademarked logo. Was there a licensing scheme in the 1960s and 1970s? Did cassette manufacturers have to pay money to Philips for every cassette tape produced? More info on this in the article would be useful. -Rolypolyman 03:06, 21 October 2007 (UTC)

Philips, Royalties, and CD-ROM

Many years ago I read an article claiming that Philips' invention of the Audio Cassette in 1963, along with tiny per-cassette royalties, made them very rich over time. Since international patents expire after 17 years, it was 1980 when Philips announced the CD-ROM as a replacement technology and then did it all over again. Maybe someone can verify this and add it to the main article. --Neilrieck (talk) 11:55, 26 January 2008 (UTC)

p.s. Take note: Philips is working with Sony attempting to promote Blu-ray technology --Neilrieck (talk) 11:55, 26 January 2008 (UTC)