It’s interesting that across all the DAT machines sony has produced, that model (which is WMD-DT1) is the only one without any recording functionality.

@Wotzinator I noticed it and I so wanted a DAT player, lol.

@@michaellu8879 as that was the most compact one 😍😍

well, there was the second impact that happened in 2000, which probably stunted general consumer technological growth

@@ulischmidt03 even by 2000 DAT was dead and CD was what everyone was using.

your first line is management, the second line is the engineers :P sound engineers don't get royalties from sales anyway, just the artists, so they didn't have the same political motivations as management, and appreciated the technical aspects just as any audiophile would.

The music industry is why we probably don't know about some great artists. It's also why some great formats are not available for us.

I love the irony.

@Kevin R. So they were proud to be some dumb criminals. Sounds like bunch of low life losers to me!

Lord Farquaad well, their leader died of a heroin overdose not long after, so he’s most likely been burning in Hell for a long time.

I think I triggered something by calling it a "fun fact" but I just wanted to share an anecdote about the DAT. I never condoned their actions. Whatever you guys do, don't tell Lord Farquaad about the System of a Down album "Steal this Album" I think his head might explode with rage! BTW evening Reginald Denny has moved on from the LA Riots, look him up. If he can get past what happened I think it's time Lord F*ckwad settle down. And yes the lead singer of Sublime died from an OD like 25 years ago so I think we can all move on and refrain from filing police reports.

We only used the format for Computer system backup for Digital VMS the old tape streamers took al night for 75MB the DAT was 2GB & backed up in 2 or less hours.

What cassettes should have been? Is he a moron? is anyone really this stupid? DAT was IMPOSSIBLE in the 60s. It could not be done. Cassettes were good enough, especially if you have a good deck. Even today, a good well mastered cassette sounds better than most streamed music which is low bit.

@@keithturner3580 Dat drives were a lot of money though. I had one, still have it. Shame they are not compatible with music.

@@tarstarkusz Yes, I agree,. I had a DAT Walkman as well as a SCSI DAT backup drive in my 486 PC. It was annoying that the computer drive did not support digital audio.

Sony loved proprietary formats

Yes, I agree

@@andrewbevan4662 loved? they haven't given them up. look at their cameras.

I can damn close to picking one up at a clearance sale in ‘93 for $300. The one that got away!

@@earlygail I later bought one for $200 broken. Took it to Sony service and they fixed it for $75 and then....yeah...I sold it for $425. :( Should've kept it)

And NO skipping when you’d drive over a big bump in the road, like what would happen with CD players at the time…

I had the Sony DAT head unit installed in my car. I was a dumb kid that spent way too much on car audio. I eventually traded it for a Yamaha Ysr50, which is miniature street legal motorcycle. I was always wheeling and dealing. Lol

@@bsd107 your car CD player skipped in 1995, weird cause ive still got the original head unit from my 1994 camaro in my car and it doesnt skip, even today though i do remember a mate had a BMW with the business CD player in his that would skip on a certain road our town had, maybe it was just me, i just remember the player in my camaro didnt, i had sony CD player in my work truck didnt skip and a sony that came with a Volkswagen bug that also didnt skip, though that one did occasionally just load then immediately eject the CD a couple times before playing.

Wait, but then what would piracy be? ... Actually, never mind that.

And you are less likely to get the perks of VD!

@@jornthree8881 wearing an eye patch, pegleg and parrot while doing it.

@@jornthree8881 Rated AAARRRR

Hahahahaha

Sadly many of them were also used and UP-sampled to 192khz for their DVD-Audio releases… Good example is the DVD Audio "The best of R.E.M." 1988-2003".

And almost every analog audio cassette in the 90s originated from a DAT master 😅

@@LupoAlbertoVB faqs 100 indeed you had to live it to know it

At 16 bit/ 48Khz?

As a mastering engineer from that period I'd say that's not far from the truth but a little way off. Most masters were recorded to umatic 1630. However master clones were almost always DAT's. Of course clones would be totally acceptable to be sent off for production providing they were timecoded and supplied with the appropriate pq data. You'd need to use something like a Sony 7050 to clone the TC from the master to keep the pq data intact.

Exactly. The limitation put on DAT by the record labels killed it as a consumer format.

Exactly the industry was so afraid of people making perfect recordings of cd’s they totally were blindsided by napster

@@donsmith5385 And it was their fault for selling LPs for $30.. (around $50 in today's money I'd guess). There were two or 3 songs people wanted, sometimes just one, and that made for a $25/song rip-off. They did it to themselves, and I really enjoyed their collapse. I was amazed at Napster, and it introduced me to 99% of the music I ever heard, but would never be able to afford (not for $25 / song). I found so much great music by accident, that it turned me into an audiophile and I ended up with over 20,000 songs in my hard drive, including hundreds of Brazilian songs my then girlfriend was so happy to be able to find. Between charging 25x the price these songs were worth, fighting against new tech, and taking hundreds of people to court, I not only think they deserved it, but was extremely happy when they ultimately failed, and U.S. courts began throwing these cases out and refusing to hear them. Couldn't have happened to a better group.. now they're obsolete. This was also a problem with video, like HDCP, and the crazy fear of TOSLINK inputs, which have finally been defeated with the help of the Chinese, who don't give a damn. You can get a $15 HDMI splitter and record from a cable box to a HDMI capture card on your PC now, and it's great quality. To hell with them.. they actually killed recording from radio and made VCRs illegal.. They failed though, because not only have I easily defeated HDCP, TOSLINK but also use SDR, which _would_ allow recording from within SDRSharp or other software, but we still have Napster's grandson, Pirate Bay for HQ copies.

To be fair, the reason DAT and MD were popular in Japan was piracy, since they sold blanks at the counter at the CD rental place.

And that’s what often kills formats. Studies doesn’t back it or are afraid it might make them lose money due to pirating.

Napster enters the chat ☠️

@@arcademania7544 napster was later, keep in mind DAT came to the market in 85

your nearly right, the record companies got scared because they already had a problem with compact cassette, people would record CDs or the radio to cassette, and the RIAA basically had dropped the ball on that one years prior thinking no one was gonna use cassette to record music, so when DAT came along and not only could it record, but it could do it with a perfect digital copy the RIAA did what they do best, they shat their pants and cried to Daddy congress that uncle sony wasnt playing nice, which then became hilarious that after throwing their toys out of the stroller they used DAT to then create the master tapes for duplication.

That proprietary digital I/O port reminds me of the controller input on NES.

@@reathareatha3870 are you sure?

I agree, DAT never really got to the point of VHS where mass adaptation of the format resulted in low prices and polished products. Plus helical scan recording intrinsically is a sensitive technology. But DAT is rock solid, mature technology compared to Exabyte which gave us big troubles, in particular when people used the drives with cheaper but unsuitable 8mm video tapes.

@@ralfbaechle I still hesitate to say DAT in computers are rock solid, but yeeaahhh.. Exabyte.. Yikes.

@@JoeMcGuire DAT certainly has a bad reputation for long term storage but I fortunately can't confirm that. A few years ago I restored all my old QIC cartridges (60, 120 and 500MB). The belt drive mechanism had failed in ways I was not able to fix. All DAT media restored just fine. All AIT media just fine. All ZIP media restored just fine. All C64 tapes worked just fine. So that pretty much contradicts common wisdom. No Exabyte to try though :-)

I always assumed this lawsuit was why Sony bought CBS Records and Tri-Star Pictures. They weren't going to get fucked by industry representative groups.

The RIAA eventually compromised with Sony and created that SCMS copy management protocol so that you can only make one digital DAT copy of a CD as per consumer rights that were ruled in an earlier court decision regarding cassette home taping rights.

​@@AnthonyMaw copy it and pass it on to the next person

well the hiss, wow and flutter was purely because cassette was analog, im sure DAT had all three of those, but because its a digital sample as long as the 1001110010 is readable by the machine it will play it back, i would also say the headroom past zero of analogs was also a bit taboo yes you could push it briefly, like really, really briefly cause it was over blow all the other music being recorded as well, but the flat out 0 point of digital was honestly not an issue for me because i just always had the recordings set properly before hand and the players knew what to do.

I wonder. Digital is all about data error correction. Like, literally, that's what Shannon, Hammering and company started with coding theory, which is what led to making computing happen and what makes formats like CDs so valuable. If you don't know how they work, you can take a look at kzfaq.info/get/bejne/qaeSm7OWudaZYac.html So what were the specific details why CDs worked so much better for the consumer, but digital tape would be less reliable than analog tape? May it be instead because tape was standardized and DAT was a proprietary format that depended on Sony, which is bad for archiving and mastering?

Indeed. Analog tape is infinitely more forgiving. For one, physically damaged sections can be spliced out; sure, the audio that was on the damaged section is gone, but everything else is fine.

@ungratefulmetalpansy First things first, no need to reply so rudely. I'm looking for constructive debate and being respectful, there's no need to be condescending nor disrespectful if I make (even outright dumb) mistakes, despite this being the KZfaq comments section. I understand the difference between discrete and concrete values perfectly, what I don't understand is how is analog more forgiving because of that. Of course you retain with it more data that can be immediately played back, whereas binary codes mean that severe enough damage would make data chunks completely lost for raw playback. But I understand that binary data should also be easier to protect and recover by design with little additional usage of storage, as again formats like CD are intended to, and there are as well digital optical formats for archival like M-Discs and Sony's more current Optical Disc Archive. On the other hand, analog media, as it is intended to be a direct replica of the content and thus lacks encoding methods, cannot be straightfowardly recovered as it is not possible to add redundancy - the only available data for reconstructing is that of the discrete data which survives damage, which cannot be automated without further guessing. I admit I haven't professionally worked in audio mastering, archiving or recovery, neither in any other environment that traditionally requires tape for long term storage, so I ask: what were the technical limitations and advantages of each ultimately derived from? Honestly, I feel it comes down to price, standardized equipment and a rather more intuitive workflow with analog (less abstract and mathematical, more tangible with readily available tools).

Xerz 1/4” tape is just extremely durable, and the way open real analog decks work is simple and much less prone to playback problems than any tape played back with a rotating drum head.

@@xerzy you're completely correct and ungrateful metal pansy is sorta wrong, just stating very basic things - binary encoding goes back even further to automated looms, so starting with Boole is a bit weird. Like the only "mistake" you made maybe was saying digital instead of "information theory" or "digital audio" specifically, but that absolutely was about strengthening signal integrity. They used binary from the get-go precisely because of error correction algorithms, and you can get extremely robust ones that have dozens of parity bits per every data bit, which are used in space to ensure recoverability even through high interference. (You don't want to send a retransmit request to a Voyager probe, which takes days to get there!) The throughput takes a big hit, but, you're totally right that that's literally what all of these codes were designed for. Digital audio has its roots in information theory and Shannon and Hamming and everyone else, as you said. Digital audio didn't spring out of thin air just because digital signals existed (such as telegraphs). And really the people who started information theory were interested in digital text representations right at the start, and later people (such as Shannon and Nyquist) realised you could encode any sequence of voltages such as audio, or small voltage readings from weather station equipment, and so on. Ungrateful metal pansy obviously can't use their brain enough to fill in "digital" to "digital audio", even though the entire conversation was about audio. Anyway, WRT DAT, I imagine it's the read mechanisms generating bad data in untested scenarios, with tape drum weirdness, and the tape being very thin and the signal being very high frequency, might make it lose enough coherence to struggle to distinguish the 1s and 0s. I don't actually know how DAT is electrically encoded, or how much error correction they use - the "bit perfect copy of a CD" is going to be about the PCM frames, as opposed to the various layers of correction in the CD's physical and encoding and interleaving stages. Maybe Sony thought, it being in a cartridge and all, that they didn't need it to be as digitally robust as a CD, which would have to resist small scratches. I don't know, I'd have to look into that more! Certainly, depending on how they actually did it, there's plenty of ways that only a very small amount of demagnetisation or tape wrinkling or so forth could completely impede decoding. And obviously every parity bit could be thought of as "wasted space", after all the CD spent 14 bits encoding 8 bits. If they removed that layer, even keeping the interleaving, a CD could hold close to 2 hours instead of 72 minutes. They obviously knew they'd stop working much faster, potentially from even a tiny scratch in that scenario, and didn't do it - but I could imagine them making that kind of decision to half the tape speed in DAT, or even just having 10 or 12 bits per 8 bit frame instead of 14, to squeeze more space, and simply be less resistant to errors that way. It certainly lasted the market length of the format, so maybe they were correct in that calculation - but it certainly wasn't appropriate for archival. (Plenty of older DAT masters do work, I assume OP simply had too many go bad that they stopped even trying, instead of them universally failing? But maybe they did universally fail, which would certainly be strange considering ones that just sat in someone's attic _can_ work.)

it's basically MiniDV, just minus the Video stream on the tape :)

Right. I have a Poor Man's DAT I record to daily. It is a Hi-Fi VCR. Has to be Hi-Fi so the audio can be written in a helical fashion on the tape and not with the audio tracking head like on non-Hi-Fi VCRs. Cheaper to do it this way as you can pick up a functioning Hi-Fi VCR for under $20 at a thrift store or get one for free. People are begging for someone to take their old units and VHS cassettes. I record over released movies on cassette. Studios released movies on high grade tape VHS cassettes. The down side is the size of the media and it is just not as cool as the DAT format, even though it is exactly the same technology.

Virgil Williams If you look at DAT, it’s actually a miniaturized Video-8 cassette.

KRAFTWERK2K6 well, except for that miniDV came along about 7 years after DAT. ;)

Phil Adams my dad had a hi-fi Betamax with both analog input/output and PCM. c.1987

I thought he mentioned that when he said bootleg concert recordings ^^ unless you mean some of these were officially sanctioned and therefore weren't bootlegs? Were any turned into live albums for sale etc? I had always assumed they hired their own sound guys to make the live albums.

Kaitlyn L there are plenty of bands that allow people to record live performances as long as they are not for financial gain. It started years ago with The Grateful Dead and continues today with bands like Phish, The Dead (3 original members of The Grateful Dead), and many others. Phish and The Dead actually sell “taper” tickets that are traditionally directly behind the soundboard. They aren’t the greatest view, but they tend to be amongst one of the best sounding locations in the venue due to how the audio engineer mixes the house.

And also that it was lossless, unlike MiniDisc which was lossy and "just" 44,1Khz. Only MiniDV was also able to record LPCM 48khz 16 bit until digital Solid State recorders became popular and replacing the tape based digital audio recorders.

@@KRAFTWERK2K6 Minidisc was introduced four years later.

Just marketing wank though. 44.1kHz is plenty high enough of a sampling rate.

Actually. I used to work with DAT machines through out the 80's and 90's and as far as I know, 44.1k was not supported. SP was 48k at 16 bit depth and LP was 32k at 12 bit depth. but as far as I know. 44.1k was never an option on any of the machines I worked with.

@@joyange1 The later models definitely had 3 recording settings, 44.1 being the third. I used the Sony D8 which could record at 44.1. The deck in this video is the earlier D7. It only had 48 for recording in SP mode via the microphone, but it would record at 44.1 if given a digital audio input from a 44.1 source (like a CD).

Me too,same opinion

I’ve actually had some experience with ADAT and while it was nice in principle to be able to use “standard” S-VHS tapes, they still weren’t very common in stores. And as you noted, reliability was often a problem (especially with the first generation of ADAT machines). I think Tascam’s product was a bit better, but both were really just an incremental improvement over the open-reel digital multitrack tape systems (DASH, etc). I think everyone was just waiting for computers to become powerful (and cheap) enough to take over.

Yep once those heads wear out, time for a new drum. .good luck finding NOS heads.

I recently looked at a functioning a-dat recorder for a really good price... Of course, those use vhs heads, which makes life a tiny little bit easier, but... good price or not... it had seen a lot of hours, and I just can't be bothered to deal with the work it would take to really bring it back to its original performance. Sure, it still worked, that is something... For digital recording (I have a-dat compatible io on my digital mixer) bringing the analogue part back to spec won't matter... but that is fun for like 5 minutes... look mum, no computer... after that, a 10 year old laptop with some daw software will do a much better job at it. The only real point in getting it would have been it also being usable as 8 analogue inputs for my mixer, but... that would involve a full restoration, and I just can't be bothered with that (not to mention, there are solutions for that which would provide higher sample depth and rate than a standard a-dat recorder will, fit in 1u, use a fraction of the power, have a fraction of the weight... you get the idea). Still... contemplating buying one for a few minutes was fun 🙂(oh, I'll need a new 19" rack... hmm, do I actually have a use for 8 more analogue inputs? etc)

@Larry XK They got hoof

I´ve made a video about DAT: kzfaq.info/get/bejne/gJ6KfJyBnMXUgYk.html

Wat is dat?

On conserve au moins le choix dans la DAT

You mean a title like DAT: kzfaq.info/get/bejne/fJp7ZLR8sLa8j5s.html (Techmoan)

here comes DAT boi, oh shit waddup

DAT was only popular in Japan because it was used for piracy. You can rent CDs in Japan and they sell blanks at the counter. A lot of places still sell blank MDs.

@@mvevitsis Yeah that's the point, is the Japanese music industry gonna crumble anytime soon?

@@AdvancePlays Japanese music industry can also get income from idol merchendise and concert.

How about panasonic sv3800, can i use dds2 on it without screw the head or mechanism? And how long tape you ofered?

And with your Metal tapes don’t forget Dolby C! ( I skipped Dolby S later as I had started using DAT instead…

Yeah I think he used S-DAT which I assume was thought to be an advancement of this.

@@PSNGormond Yeah it was the (then) future after all

An alternate timeline where the music industry had reminded itself: "I mustn't run away!"

To be fair, that connector attaches a dock that had a LOT of functionality. I had the Walkman D3 (the predecessor to the one in this video) and that RM-DK10 allowed optical digital in and out, RCA digital in and out, and came with an IR remote. Really nice setup. Also, the D3 shipped with a simple optical digital cable (toslink) that had that customer connected on one end. So, you could still make digital copies of CD’s right out of the box without having to buy the RM-DK10. They also didn’t use this connector on the home units - it was on the Walkman’s to save space…

that's because it was.... en.wikipedia.org/wiki/Digital_Data_Storage

They are. Some DAT systems will even accept them as-is.

I think Sony extended DAT into a data storage format

Davey656 exactly!

I use new old stock HP data tapes with my DAT recorder. It doesn’t seem to notice any difference.

I worked as a backup operator at the same time with DATs too.

Ahh..

Plus the transition between the states would be pretty obvious, regardless of the amplitude. Literally the reason we switched from AM to FM radio, since most interference affected only the amplitude. As long as it could pick it up at all - and as you say, it's 5x higher on SPDIF than 200mV peak to peak!

Yes, you remember that correctly, and hence, pretty much everything which uses aes3 will accept spdif on its inputs... the other way around.. read the documentation of your aes3 capable device as many can output spdif level signals when asked to, which seems like a good idea.

But, as far as I can remember I was able to record at 48kHz.....

the actually problem is the main gears out of alignment, no many people can fix them now.

I have a Sony PCM-2700A that does 44.1 and 48, but it’s a professional audio deck that was never marketed for home use. All the decks that were marketed for home use only recorded at 48 to prevent direct digital copies of CDs in an attempt to appease the RIAA.

dds-1 tapes can double as dat cassettes

@@RagedContinuum The only problem for DDS is the tape itself is too thin if u put DDS into DAT audio player then hit play/record I can guarantee you will get most tapes jammed for sure because due to design of DAT audio machines the pickup roller not quite like thin tapes.

It was renamed DAT by HP later on, and the last iteration of HP's DAT had a twice as thick cartridge, as they had doubled the tape width, breaking all compatibility with previous DAT/DDS iterations. It's been over a decade since they released the final iteration, though. Some companies might still use it, but DDS/DAT is dead, like many of the other tape formats. LTO is essentially the last man standing in the tape backup market.

just use 60 meter or less DDS-1 tape only and you should be fine

@@RagedContinuum really?? I used 120mins DDS no wonder the tape jammed big time. thanks for that

in 2008 solid state recorders were expensive?? uhh no they werent dirt cheap like now, but freaking computers had either the same quality or slightly better ADC's as the Dat units would have, yes they had mechanical hard drives but still that more reliable than dat

Yeah and some decks (especially the bigger ones) also have a metallic rod that may bend too much if you push in the tape with too much force… resulting in the machine eating your tape. Also, congrats on getting your portable DAT fixed again :D must have been quite a lot of work.

skonkfactory It is!!

iqi616 VHS HiFi is criminally underrated as an audio format. It was my go to for home use from 1986 to 1999. I wish I still had all my tapes but my ex-wife jacked and lost them all during my divorce in 2002.

Yeah wasn't there even DAT recorders who could also record 96Khz 24 bit? Like some MinIDisc decks and portables could record 20 and 24bit.

+KRAFTWERK2K6, Certain professional recorders could indeed do that, although I believe it's technically outside of Sony's specifications.

@@Dan-TechAndMusic Yeah. Never really saw it widely used. Except for the standard 48khz / 44,1Khz 16Bit. I wonder how compatible these recordings were with other decks who could playback that kind of different recording specs?

Have you ever thought about getting a MiniDisc Drive for your PC as well? I know those existed but weren't really widespread. Technically those could be used to read out the raw ATRAC data as well and making 1:1 dumps of the digital audio on the MiniDiscs. With modified firmware :)

I've considered it, but those drives are even more rare and expensive. I managed to get my DAT drive cheap, else I wouldn't have gotten it either.

Yeah DAT standard is 48khz 16Bit PCM audio with 44,1khz just being an extra for CD. I think Colin mixed up DAT with MiniDisc and HiMD which both indeed could record ONLY 44,1Khz, with the option to 16bit, 20 bit or 24 bit (just for regular MiniDisc, not HiMD), depending on the recording deck or portable.

Nope, DAT can record in 44k1, 48k or 32k (the so-called “lp” mode). It depends on the clock source, so when you copy a CD over s/pdif, the dat recorder gets in sync with the CD player, thus making a perfect bit-per-bit copy of the cd at 44k1 16bit (there were also some high end dat recorders which went up to 24bit-48k).

Unless you have a Pro level studio DAT it will only accept 44.1 digital in. it can only record anlogue sources in either 32k or 48k.

Losing Weight, Ripping Vinyl Actually no. Early DAT units could not accept 44.1 digital input. But later ones could, either by using a built in sampling rate converter to convert to 48, or in later ones by doing native 44.1 recording.

KRAFTWERK2K6 FYI, while a handful of MiniDisc recorders (like the MDS-JB920) could output 20 and 24 bit, the recording on the disc is still 16 bit. Well, sorta: the way MD works, it records a mantissa and an exponent. So MD is, in effect, capable of floating between 16 and 20 bits, depending on signal amplitude. The DACs in those higher end decks were 1-bit delta-sigma converters and thus could actually render that properly. (I have an MDS-JB930 in my home theater system. :) )

BTW, I remember have read an article by Stephen St. Croix, a MIX magazine columnist I used to adore (resting in peace now) that DATs had a terrible error correction rate, and he was able to prove that 1:1 digital copies done in DATs will differ (data wise) from each copy generation due to the error correction algorithms, mostly caused by inconsistencies on tape media coatings,or due to friction, head misalignment, transport issues and others. I had really hard times when listening/mastering to certain DAT tapes that were recorded on different equipment than mine, and I had 3 decks! (DA-30, SV-3800 and that tiny D7). That probably add up to why they disappeared...

@@juanfebresc That's interesting to note, I have asked elsewhere on here what the deterioration of tape was like compared to the standard cassette.

That does not...compare (techmoan is on another level)

to be honest i prefer Colin's videos a bit more over Techmoans kinda over-produced videos.

@@KRAFTWERK2K6 I think both are good in their own way though i don't agree techmoan is over-produced in fact he's one of the least, his level of production goes as far as acting with wigs and muppets that's about it can't even be bothered to trim his nails

@@KRAFTWERK2K6 It's about knowledge of the audio players and mediums. I see a lot of mistakes here on that subject. I watch them both, of course

@@octap79 Same same :) If you love vintage AV technology, you just gotta watch em all.

I got one of these when I was in college. It was a dream machine for me at the time. Loved it. A little big and heavy, though, with the battery attached, especially compared to Discman models which were already quite small by then….

lucky

And compatibility, some of my studio clients would bring in tapes made on other models of DAT machine and I had trouble paying them. Even my own tapes had some errors.

The existence of minidisc is one of many things which came to mind when I saw the words “What cassette should have been”, along with the fact that digital consumer-grade tape definitely didn’t exist when cassettes were invented. I really don’t understand why people come up with video titles so gimmicky that they don’t even make sense.

@@jamescarter3196 From what I know the quality of the DAT tape was far superior than the metal chrome type, if I remember right I think you could do proper track search and stuff 👍🏼

Yeah, part of the video that got cut for time went into how the music industry basically forced SCMS to exist - but by the time the tech was ready and available in DAT products, the format was DOA with consumers. Professional DAT decks often had the ability to enable and disable SCMS on demand.