MiniDisc Lifespan

[zahne]

According to B&H Photo, HHB blank MDs have a 50 year archival life. I'm not about start backing up all my audio on MDs for archival but my production company uses three sources for all audio: hard disk (either HDD or SSD), Blu-Ray (BD-R Archival Grade) and original source (i.e. tapes or minidiscs if not recorded directly to hard drive). So is there any validity to this 50 year lifespan claim? Anyone have MDs from the early 90's are ready to kick the bucket? We still record on MD for projects because it's cheap and the quality is acceptable for what we do. All that audio is archived on modern media, like I said, but it's good to keep original source material in case hard drives crash or BD-Rs get scratched or burn in a fire etc. It's simply good to have that safety net of the original source. So anyone know if maybe Sony ever said in press release what MDs were designed to last for?

[bobt]

I live in what can best be discribed as a harsh climate for electronics and media, close to the ocean, high humidity, high average temperatures, and a high salt concentration, in 15 years I have lost about 3 to 400 CD's due to the reflective layer dissolving, in ten years I have not lost a single MD, a couple have taken unexpected sapt water baths, sill running, I think they will last

Bob

[pata2001]

Backup is useless if you cannot restore it. Would you have a HiMD reader 50 years later? I'm sure in 50 years, one can still buy an optical drive to read CD/DVD.

[zahne]

Backup is useless if you cannot restore it. Would you have a HiMD reader 50 years later? I'm sure in 50 years, one can still buy an optical drive to read CD/DVD.

I don't mean to back up. If the MD was the source of the recording it would simply be a decision to archive the original source. HDD and BD are my main archival methods. But that's interesting about the whether conditions.

[bobt]

I have reel to reel tapes that still play, some of them are well over 30 years old, get yourself a Revox or TEAC reel to reel and some tapes and you will be good to go

Bob

[kino170878]

If you are in the professional field and are interested in using MD for archiving, I would suggest only going for standard MD (SP 292kps) and not Hi-MD since Hi-MD players are soon likely to be rarer than hen's teeth. Company's like Tascam (and even Sony I believe) are still making SP decks, and Tascam have no plans that I know of to stop production. I think Sharp even continues to make an SP portable, though it's the decks which are of most interest given their greater number of inputs/outputs and ease of control.

[kino170878]

Minidisc was around for a good 10 years before Hi-MD so it already has a proven longevity. I assume the thread starter is satisfied with the compression format of standard minidisc, if not then yes uncompressed PCM WAV would be the way to go. But as you already state Hi-MD players won't be around after a while. It's a tradeoff like all things in life

Edited May 7, 2009 by kino170878

[zahne]

Minidisc was around for a good 10 years before Hi-MD so it already has a proven longevity. I assume the thread starter is satisfied with the compression format of standard minidisc, if not then yes uncompressed PCM WAV would be the way to go. But as you already state Hi-MD players won't be around after a while. It's a tradeoff like all things in life

Well, once we grow and have a better budget we'll probably just have an HDD or SSD based portable recorder that can record lossless audio. I'm only talking about keeping our original source material that is on MD and not deliberately backing up all of our audio to MD. As a safety net when all else fails. But yes we are satisfied with the ATRAC codec sound quality, once it's captured and put into soundtrack pro and logic and mixed into a 7.1 surround mix, the viewer isn't really going to tell. If there are 70 people in a movie theatre hearing a 7.1 soundtrack that has at least 2 ATRAC channels the one audio aficionado in the crowd will pick up on the lossy sound (if that). From my experience, I've presented PCM and ATRAC audio to many people and no one has noticed at theatres or with headphones on with the audio pressing against their ears. Considering that and the fantastic price that standard MDs are it's good set up for now. I have a Sony R70 I got for $10 and blanks I got for $1 each. PCM would be good for our better funded projects but for right standard MD is A-OK.

[ceramiccactus]

I have 25 Sony MD's from 1995 that I re-record over almost everyday. They work flawlessly every time.

I have never had a disc go bad on me.

[zahne]

I have 25 Sony MD's from 1995 that I re-record over almost everyday. They work flawlessly every time.

I have never had a disc go bad on me.

Any mechanical failure from so much use?

[PhilippeC]

very interesting post

I was just yesterday ordering to a friend a new MZ-RH1 just to be sure to have one in perfect state.

The one I got in Vietnam does not look to be able to live a long time. I do not have any remote.

I have a MZ-RH900 that work well but it has still a problem to reach the editting menu and my remote died already.

I have supported many HDD crash and already lost 100 Gb of music. My internal Creative X-Fi audio card died also. My two first MP3 readers died after 2 years.

My Ipod 5.5G need to be charge 2 or 3 times a week.

20% of my original CDs have reading problem.

50% of my DVDs have the same problem.

So I hope that MDs are safer. They cost 4 times more than a basic CD-RW but can be re-use 1.000.000 times. I still can find them in Vietnam 1,2$ each.

I think that every thing whitch is not inside a computer is at a safer place...

Thanks

[ceramiccactus]

Any mechanical failure from so much use?

None at all.

[zahne]

Let me pose one more question. Would this be the archival lifespan HHB blanks or is it the nature of MiniDiscs b/c of its technology?

[stormtrooper]

Some of my recorded minidisc is 10 years plus. Its working fine and very durable. I guess it will last for decades to come.

[Levanel]

Maybe Sony or any other MD manufacturer should take into account the durability and lifespan of units more than the media themselves..

[Leandro]

I remember reading about an experiment done which involved "accelerated ageing". This involved a lab test in which SP MDs were put in a kind of oven that simulated the effects of decay caused by time. They found that the MD's still worked perfectly after a simulated period of 100 years!

If only I could find where I read about this, then I'd show you it, but I swear something like this was carried out.

[tophtml]

I have reel to reel tapes that still play, some of them are well over 30 years old, get yourself a Revox or TEAC reel to reel and some tapes and you will be good to go

Bob

The R2R players are workhorses, I still have 2. The problem is the tape. Between the bonding agent which bonds the metal oxide to the mylar and the shedding oxides, the tape only lasts a, relatively, short time.

[mmp64]

Yep, as said, archiving on MD is only worth it if you keep one or more NIB RH1's in the underground vault of a Swiss bank.

The magneto-optical media will surely last for a long, long time, but the MiniDisc reading / writing devices likely less.

Multiple backups on multiple formats in multiple locations seem most likely to guarantee perennial safekeeping.

Not quite a Swiss vault, but I've purchased a couple of 505s and 510s (they seem to be the sturdiest, and they can use any AA battery) - put them in sealed plastic bags, then in a storage bin and put that in a cool, dark room. I'm 44 - so I'm thinking by the time those units go, I'll either be deaf or won't care.

In general - I've been disappointed with the durability of HiMD units - battery problems, read problems, etc. I bought a used 505 probably 7-8 years ago, ripped a 5-600 CD library on it twice (at least) - and it still works.

[Odyssey]

My view on back ups has not changed for many years.... The Minidisk is not meant for first gen back ups or Masters. The Encryption takes away, though miniscule, some of the excitement of the recording. And if you were to record the MD to a CD or tape and re-record to MD, the second encryption would make it very noticable.

I currently use CD as first gen MASTER copies. I will make a compilation from the MASTERS to the MD for my portable listening enjoyment....

I can erase part or all of the minidisc for a new compilation whenever needed.

If you record a first gen to minidisc, such as remote nature sounds, and save the sound on the MINIDISC, you are good but you can only record to a CD as second Gen and never back to MD as 3rd gen. Well you could but it would sound like a frog croaking.

In the case of using the MD for remote recordings, you won't have a lot of choice since the 1st gen recording was on the MD so just live with the fact that copies will be limited.

As far as life span, it is a coin toss. Of the discs I have used, mostly SONY but some memorex, etc... I have only had 2 discs actually fail where it would not record again. That would be less then 1% of the discs I have used.

The "iffy" one is when the TOC fails. Again, I find this occurring another coin toss. There are many reasons it could happen, including low batt, MD Recorder being dropped/bumped, static, more distant reasons, md recorder failure, and more. I have not had it happen often, but it has happened a couple times. do everything you can to restore the TOC and you won't lose anything.... been there, done that....

Keep those MD's spinning

[sfbp]

Aren't you mixing up compression artifacts and encryption? The two are entirely unrelated except for the rather feeble argument (contradicted by Sony's making "pro" equipment that allows copying, and of course the RH1 which genuinely does upload the unaltered bit patterns off a pre-hiMD disk) that Sony did this (prevented copying) to avoid "degraded" copies getting out and spoiling their reputation for good sound.

Encryption does nothing to sound quality.

Compression doesn't prevent uploading.

Yes?

[bluecrab]

My view on back ups has not changed for many years.... The Minidisk is not meant for first gen back ups or Masters. The Encryption takes away, though miniscule, some of the excitement of the recording. And if you were to record the MD to a CD or tape and re-record to MD, the second encryption would make it very noticable.

Keep those MD's spinning

I've done some MD > CD > MD recording, and the result is pretty much all right (that is, the second MD) so long as the source is of good quality. Of course, that applies to any recording to or from MD. I do not generally backup MDs, but on occasion do back up the source.

Other than when I'm where I'd expect to hear them, I haven't noticed any frogs croaking ;-)

Still spinning!

[Odyssey]

Aren't you mixing up compression artifacts and encryption? The two are entirely unrelated except for the rather feeble argument (contradicted by Sony's making "pro" equipment that allows copying, and of course the RH1 which genuinely does upload the unaltered bit patterns off a pre-hiMD disk) that Sony did this (prevented copying) to avoid "degraded" copies getting out and spoiling their reputation for good sound.

Encryption does nothing to sound quality.

Compression doesn't prevent uploading.

Yes?

==================================

It does not matter whether it is encryption or Compression, ( compression would be the one )the act of recording uses both and the quality may have a subtle change, barely noticeable in the MD 1st gen. Sorry I don't have the numbers but I think it is a ratio of 1 to 6 where from every 6 bits, one is removed. But for a MD second gen recording, the same 1 out of 6 bits is removed making a second bit removed from every 6 bits in the recording, a factor of more then double removed ( 1st and 2nd gen combined) thus the loss becomes more preveilant. I have never done a 3 gen recording but I can't imagine it sounding very good since more than half the data bits would have been removed.

I have used a 1st gen MD recording to record to a CD but I never expect it to sound great if recorded back to a MD for 2nd gen. I have only done it once when I did not have a CD Master recording. I would say it was ok but.......

The best way to preserve your recording would be to CD for your Master.

Use the MD for making any compilations you want to listen to on the road, riding a bike, walking a path, etc. make changes when you want or erase and compile a new session from the CD Master(s).

This will become especially important when MDs become very hard to find.

Keeping compilations on the MD may not be possible, or not all of them anyway. CDs are plentiful and make good MASTERS. MDs are great for portability. Its strange that we have these amazing portable editing sound stations, yet they are becoming an endangered breed... What a waste of great technology..............

A fast thought here..

Imagine how much music you could save, if they used the MD compression on the CD disk.

Keep those MD's Spinning

[sfbp]

Sorry I don't have the numbers but I think it is a ratio of 1 to 6 where from every 6 bits, one is removed. But for a MD second gen recording, the same 1 out of 6 bits is removed making a second bit removed from every 6 bits in the recording, a factor of more then double removed ( 1st and 2nd gen combined) thus the loss becomes more preveilant.

Don't think that's quite right.

Suppose you get a 10% loss on the first transcoding. (100->90) There's no reason to suppose you would lose MORE percentage wise on the second transcoding, ie 90->81 not 90->80, and certainly not 90->89 (or worse).

I have used MD's as a way of capturing digital sound and generating CD masters. I can put up with the loss of the 10% (or whatever it is, I suspect much less, instinctively I am guessing 5% or smaller) because I don't lose anything after that (and because when I do that step I can clean up the sound quite a lot). So for me the CD (or PC) is the backup to the "original" MD recording.

When all is said and done, I think we basically agree.

[philippeb]

If you record a first gen to minidisc, such as remote nature sounds, and save the sound on the MINIDISC, you are good but you can only record to a CD as second Gen and never back to MD as 3rd gen. Well you could but it would sound like a frog croaking.

In the case of using the MD for remote recordings, you won't have a lot of choice since the 1st gen recording was on the MD so just live with the fact that copies will be limited.

Or buy a used MDS-W1 and enjoy unlimited 1st gen MD copies. Sorry for repeating: the MDS-W1 is _the_ answer to the MD archival/backup problem discussed here. You will also get 1st gen defragmentation, a must if you edit a lot.

[sfbp]

Or buy a used MDS-W1 and enjoy unlimited 1st gen MD copies. Sorry for repeating: the MDS-W1 is _the_ answer to the MD archival/backup problem discussed here. You will also get 1st gen defragmentation, a must if you edit a lot.

Philippe, are you sure about this?

Looking at the schematic for the W1, it seems that the connections between the deck are normal S/PDIF connections, switchable between direct connection and optical in. Would you agree with me that the ATRAC converter lies after this level of signal?

If that's the case then really the MDS-W1 is nothing special, just two decks (specifically MDS-JE520's) hooked back to back.****

Now comes the potentially interesting part. If you are correct in your claim about no loss (and I don't doubt you on this point), then the ATRAC transform itself is essentially "Magic", and mathematically ensures that ATRAC->S/PDIF->ATRAC is the identity matrix.

Now THAT is the magic of ATRAC, to me. You can go to and from 1411Khz (from ATRAC 292kbps) with no loss. All the years I have been using MD's to capture sound, and then create CD's from them, suggest that the conversion FROM ATRAC to CD is lossless (my ears might have argued, otherwise). Incidentally, going the reverse direction is clearly not 100% lossless but if you started with ATRAC then you will finish with the same ATRAC. And as long as the PC or CD drive reproduces what really was on the CD accurately, then you will get back the same bit patterns on the other MD before it got sent to the CD.

Stephen

**** except one small thing, the MDS-W1 does it faster than real time. Note that the conversion of SP to WAV is well understood by Sony's software engineers and the #linux-minidisc group, and it is, mathematically an extremely simple transformation. This is how the RH1 can upload at x10 with "perfect" conversion to WAV.

[philippeb]

Philippe, are you sure about this?

Looking at the schematic for the W1, it seems that the connections between the deck are normal S/PDIF connections, switchable between direct connection and optical in. Would you agree with me that the ATRAC converter lies after this level of signal?

If that's the case then really the MDS-W1 is nothing special, just two decks (specifically MDS-JE520's) hooked back to back.****

Now comes the potentially interesting part. If you are correct in your claim about no loss (and I don't doubt you on this point), then the ATRAC transform itself is essentially "Magic", and mathematically ensures that ATRAC->S/PDIF->ATRAC is the identity matrix.

Stephen,

What makes the W1 unique is the disc to disc MOVE function. That function bypasses the ATRAC decode/reencode steps, and directly copies ATRAC data from disc to disc. The copy occurs at 4x real-time speed, because only compressed ATRAC data bits are transmitted between discs. I insist: this is a bit to bit copy (even if the disc layout can differ when defrag is involved). For the record, the trick: after MOVE completion, one have to super UNDO the source disc to actually achieve the perfect 1rst gen copy.

The W1 also permits the usual deck to deck copy, ie ATRAC -> decode -> transmit -> reencode -> ATRAC, that honours the SCMS protections: decoded bits are transmitted in the digital domain when allowed, otherwise they are transmitted via the built-in analog connection. I never use that regular lossy copy function (why would I when I can do lossless copies with MOVE ?), except when I want to copy from STEREO to MONO, or change the recording level.

[sfbp]

Have you copied a disk, uploaded each with RH1, converted to WAV and done a file compare, then? If what you say is true then this should work, I think.

Can you show me the signal path on the circuit diagram? Again I don't doubt you - I want to believe.

[philippeb]

Have you copied a disk, uploaded each with RH1, converted to WAV and done a file compare, then? If what you say is true then this should work, I think.

Here you are:

$ ls -l *.wav

-r-------- 1 felix users 27417196 Oct 4 18:33 001-Jacques Grello.wav

-r-------- 1 felix users 27417196 Oct 4 18:33 036-Jacques Grello.wav

$ cmp *.wav

001-Jacques Grello.wav 036-Jacques Grello.wav differ: char 27370545, line 264673

$ cmp -l *.wav | head

27370545 301 300

27370655 111 112

27370659 331 332

27370661 175 176

27370665 24 25

27370679 170 171

27370703 221 222

27370707 307 310

27370717 303 304

27370729 317 320

First 27.370.544 bytes are strictly identical. Last 46.652 bytes differ slightly. That is is probably a firmware bug, that can easily be circumvented: pad the track with a sound quantum; copy; remove the padding. Practically, the difference is unnoticeable, except in rare cases where sound does not fade at the end of the track.

[sfbp]

Those are data, right? Too much for a digital copy imo.

But as I say, my theory that ATRAC->S/PDIF->ATRAC is uni-whatsit would still produce something like this.

Did you take a look at the service manual schematic? I would expect to be seeing a physical interconnect between some pre-decoded data on one drive and the DSP chip on the other. And I don't.

Either way it's amazing. Now the question is, can it be reproduced with an SCMS-killed regular copy? Or one made without digital amplification by making a WAV file and transferring it back to an SP disk?

Stephen

[philippeb]

Those are data, right? Too much for a digital copy imo.

But as I say, my theory that ATRAC->S/PDIF->ATRAC is uni-whatsit would still produce something like this.

Did you take a look at the service manual schematic? I would expect to be seeing a physical interconnect between some pre-decoded data on one drive and the DSP chip on the other. And I don't.

Either way it's amazing. Now the question is, can it be reproduced with an SCMS-killed regular copy? Or one made without digital amplification by making a WAV file and transferring it back to an SP disk?

Stephen

I am unable to read the schematic. But I know for sure that the W1 does ATRAC domain copies, that avoid ATRAC decoding/encoding stages. I can ear the difference between a 1st and a 2nd gen track, and I can assure you that the W1 does 1st gen copies. I never pay attention to which copy is the original, because they all are.

I usually edit my current MD hundreds, if not thousands, of times. Each time fragmentation becomes excessive (too many seeks required, to much space lost), I do a full copy on a blank disc, and restart editing from there. The defragmentation that accompanies the copy typically recovers 1 or 2 minutes of recording time from a full disc.

I often repeat that procedure many times while composing a single disc. When I am done, the final master MD will have been copied half a dozen times. And I will make one more copy for my wife, or for friends. And all those copies will be as many more master copies. I have never lost an "original" recording, with the blessed W1.

SCMS bits are ignored, because they control how tracks are copied, not moved :-) SCMS bits are copied along, regardless of their values. My guess is that the generous Sony engineers that built the W1 were perfectly aware of what they were doing: they deliberately suppressed all copy restrictions, but could not advertise it :-(

As I said in an earlier post, I would not have invested in MD, if the W1 had not existed. IMHO, the capacity to make perfect copies is the essence of digital recording. I was looking for a durable, convenient, versatile, physical medium, and I found it. Again, I do recommend the MDS-W1 for long term original sound recording archival on MD.

[sfbp]

I am unable to read the schematic. But I know for sure that the W1 does ATRAC domain copies, that avoid ATRAC decoding/encoding stages. I can ear the difference between a 1st and a 2nd gen track, and I can assure you that the W1 does 1st gen copies.

So here's the question: if I can do the same thing by uploading SP to WAV and transforming back to SP, would you believe my assertion about the mathematics of it?

At the moment this is a thought-experiment, as there is no software encoder WAV->SP, although there IS a software decoder SP->WAV

From what I can see, there is NO magic whatever in the hardware circuitry. And there should be.

[philippeb]

So here's the question: if I can do the same thing by uploading SP to WAV and transforming back to SP, would you believe my assertion about the mathematics of it?

At the moment this is a thought-experiment, as there is no software encoder WAV->SP, although there IS a software decoder SP->WAV

From what I can see, there is NO magic whatever in the hardware circuitry. And there should be.

Oh now I got you (sorry, I did not understand what you meant earlier). Again, observing the W1 as a black box, one can distinguish three different copy modes between deck A and deck B:

Fast (4x) lossless W1 MOVE:

ATRAC data read|digital copy|ATRAC data write

Real-time lossy digital copy:

ATRAC data read|ATRAC decompression|digital copy|ATRAC compression|ATRAC data write

Real-time lossier analog copy:

ATRAC data read|ATRAC decompression|digital to analog conversion|analog copy|analog to digital conversion|ATRAC compression|ATRAC data write

How this is implemented in hardware, I do not know. From what I have read, ATRAC compression/decompression is asymmetric and lossy, by design. Therefore, I am not comfortable with your hypothesis.

[sfbp]

Right. You are saying there are three modes.

I see nothing in the hardware that convinces me that more than 2 modes exist. But I have asked a hardware-expert friend this question too.

One more point: your statement "ATRAC compression/decompression is asymmetric and lossy" I totally accept. Otherwise you'd be breaking the second third law of Thermodynamics, more information in than out.

But I believe the statement "ATRAC decompression/compression is lossless" may well be (and should be) true.

Consider Sound C on CD. C->A->B is clearly going to be a lossy process where B is once again on CD.

But if you take B and transfer to MD(->D) and back to CD, it should be lossless.

Just as A(MD)->E(CD)->F should yield F is identical to A, give or take a few bits (as in your experiment). The key in this case is that you have two identical decks with identical chips and identical encoding characteristics.

Stephen

[philippeb]

Right. You are saying there are three modes.

I see nothing in the hardware that convinces me that more than 2 modes exist. But I have asked a hardware-expert friend this question too.

The author of the minidisc.org MDS-W1 page http://www.minidisc.org/part_Sony_MDS-W1.html seems to confirm my perception. I quote:

Unusual "Inter Disc Move" function will move a song from one disc to another at 4 times realtime, defragmenting the copy and deleting the original. The move is done losslessly in the digital domain with raw ATRAC data.

[sfbp]

The author of the minidisc.org MDS-W1 page http://www.minidisc.org/part_Sony_MDS-W1.html seems to confirm my perception. I quote:

Unusual "Inter Disc Move" function will move a song from one disc to another at 4 times realtime, defragmenting the copy and deleting the original. The move is done losslessly in the digital domain with raw ATRAC data.

OK, maybe it's time for me to get brutal.

1. You can't prove that my previous explanation is wrong

2. You can't point (neither, so far, can anyone else) to something in the hardware showing any physical connection how this "fairy-tale" version can be accomplished. There are plenty of (more, or less, wildly) inaccurate statements in that website, so this would not be an isolated occurrence. Whoever did it (Eric W?) based their information on the best that was available at the time (and there were probably no service manuals when that page was written).

3. The few errors you see may well be related to something like frame completion/roundoff/skipping/padding, as you yourself admit. That's exactly what you would expect with some timing or other errors associated with a digital (coax or optical) transfer.

I imagine the 4x can be done by changing the frequency of the clock, correct? 176.4 is not exactly unknown these days, there are plenty of hardware devices that support it. Even in 1998.

Stephen

[netmduser]

I am curious and will look into the hardware (service manual).

However, I would revise the experiment to an improved experiment with RH1.

Take MDa and copy to MDb, MDc.

File compare MDb and MDc.

They should be exactly the same.

Then copy MDb to MDd and compare.

The outcome of this result could settle the question here.

[philippeb]

I imagine the 4x can be done by changing the frequency of the clock, correct?

Yes, Stephen, you must be right. I am not competent in hardware, and I had not thought of that. I could only imagine 4x less data being transfered. Thank you for your explanations!

[netmduser]

On page 12 of the user manual there is a title copy function md to md. Does this not imply ATRAC to ATRAC direct data copy? Does this mode run at 4x? Can titles be copied through SPDIF? This could rule out one of the modes?

[sfbp]

Yes, Stephen, you must be right. I am not competent in hardware, and I had not thought of that. I could only imagine 4x less data being transfered. Thank you for your explanations!

Finally maybe you're starting to see my point (and it's only a point). Now, please, don't take it as read, I am not a H/W expert either. I am still hoping to get some more answer from my hardware expert friend.

Couple more points:

1. See page 52 (of the MDS-W1 service manual). I am not sure what this is but I see some frequency dividers, that seems rather suspiciously like what we are talking about.

2. If I had 2 decks with coax (less sure about optical because I believe it's not so accurate) I could probably rig something that looked like the MDS-W1. Unfortunately I don't. There's also the problem of SCMS, which we KNOW Sony can solve by tweaking the chip the way they want to (see their Pro Decks which use all the same basic hardware).

So mine is in essence still a "thought-experiment". But Schrodinger and Heisenberg relied on same or less

I wonder if converting one of the CD-MD decks would be possible. I don't see any sign of the divider circuit in there but that maybe because 18-bit oversampling has been routine for CD's forever (and that's all you need, right? 4x is just 2 more bits). So one might be able to clone the idea, just not with x4 speed. Presumably the difference between highspeed and normal on the CD-MD decks is something about this, where you reduce the oversampling (perhaps from 20 to 18?).

Stephen

PS were it not for your pointing out of the remarkable properties of this unit maybe no one would have ever figured this out.... thank YOU!

[sfbp]

On page 12 of the user manual there is a title copy function md to md. Does this not imply ATRAC to ATRAC direct data copy? Does this mode run at 4x? Can titles be copied through SPDIF? This could rule out one of the modes?

That's the function we are talking about. Unless you mean cloning of the TOC entry (copying the title), which is indeed possible because it doesn't go through the S/PDIF interface at all.