What is the lifespan of a minidisc?

[Sony_Fan]

How many times can you record/erase the following minidiscs, before it becomes damaged/useless?

- 74 min

- 80 min

- 1 GB

[greenmachine]

http://minidisc.org/faq_sec_3.html#_q10

[Sony_Fan]

http://minidisc.org/faq_sec_3.html#_q10

That's what Sony claims. I want to know the real lifespan.

[raintheory]

Well I don't think anyone here keeps a running count of how many times they use a particular disc...

That said, I know I have discs that I have used well over 100 or more times. Also, I still have the first discs I purchased (they were 60min back then) and they still work fine.

There is a possibility that environmental factors or mechanical failure could ruin a discs lifespan.

Although if you'd like to test this, assuming you can do one write/erase/rewrite cycle a minute... It would take a couple years to reach a million cycles, and that doesn't factor in sleeping or bathroom breaks!

Edited August 3, 2007 by raintheory

[BobS]

MO technology has been around far longer than MD. The reason it has lasted is the reliability of the media. Sony's claim is probably based partly on this history. I have used 128 meg MO disks for backups that have been repeatedly used for over 10 years. I know this does not directly translate to MD's MO, but the technology is very similar, the MO layer being a lower temp. MO material. I would think it very difficult to wear out a disk, far more likely the recorder

[bobt]

my thoughts, they will record until they won't. There can't be a single number that you say after this watch out, too many variables.

U have several thousand albums from the fifties to the nineties, all still play last I heard. I have several hundred cd's, probably 1/3 of them are faded to unusability from the high humidity and salt environment. Same goes for cd-rom, unless they are handled with felt gloves, they scratch themselves into oblivion. In about seven years I haven't lost a minidisc due to dropping, soaking it in the ocean, listening to it on the beach, opening it to see how it works, not one lost. I think that translates to reliability.

Bob

[tekdroid]

if I'm not mistaken, the fat filesystem makes lots of writes to the same part of the disc every time files are updated, etc. I think 1 million is within easy reach on an often-changed disc.

[Sony_Fan]

I had one minidisc that I bought back in 2000. I recorded music on it and when I played it back, some parts of the music sounded distorted and low quality. The same kind of low quality when you listen to wrinkled tape on a cassette. Then it hit me, the cassette records using magnets and so does MD. When you record/erase a cassette, the sound quality is diminished and so I wondered if the same would happen with MD.

[raintheory]

The difference is that cassette tape is Analog and MD is Digital.

Also the tape itself comes into direct contact with the playback/record heads at all times during playback/recording, and I think alot of signal degradation in analog tape is due to the magnetic fields that are created on the recording/playback heads from so much tape passing over them. http://en.wikipedia.org/wiki/Cassette_demagnetizer

Edited August 4, 2007 by raintheory

[Sony_Fan]

The difference is that cassette tape is Analog and MD is Digital.

Also the tape itself comes into direct contact with the playback/record heads at all times during playback/recording, and I think alot of signal degradation in analog tape is due to the magnetic fields that are created on the recording/playback heads from so much tape passing over them. http://en.wikipedia.org/wiki/Cassette_demagnetizer

I understand that, so basically you're saying that a brand new minidisc would produce the same sound quality as one that has been recorded/erased 100 times or more? I believe that a brand new minidisc would always produce more sharp, crystal clear sound than a used one.

[sector001]

it lasts a pretty long time, i record and erase 5 times a week. i listen to a radio program. i had to only use a new disc once. but i dont know, i never kept count.

[Strungup]

my thoughts, they will record until they won't. There can't be a single number that you say after this watch out, too many variables.

U have several thousand albums from the fifties to the nineties, all still play last I heard. I have several hundred cd's, probably 1/3 of them are faded to unusability from the high humidity and salt environment. Same goes for cd-rom, unless they are handled with felt gloves, they scratch themselves into oblivion. In about seven years I haven't lost a minidisc due to dropping, soaking it in the ocean, listening to it on the beach, opening it to see how it works, not one lost. I think that translates to reliability.

Bob

Dropping in the Ocean ???? ..... New meaning to Billy's name eh ! ( get it ? Billy Ocean ???)

Opening it to see how it works ,....... We never really grow up do we

[tekdroid]

heavily scratched CDs and things like that can degrade the sound of the disc because the cd player itself interpolates (guesses) the missing data. But it's not something the average user can pick up, normally.

I believe MiniDisc works the same way.

What matters with mediums like MiniDisc is the chemical stability of the medium with regards to writes/rewrites (and of course wear from the magnetic head, which actually touches the disc). All these things add up over many cycles.

Digital or analogue, both cd and cassette (and md) are still reliant - in the end - on old-fashioned chemistry and the chemical properties of their mediums (and hardware) in doing what they do. Degradation with digital just has different characteristics (ie. not normally noticeable, or totally noticeable). Though there is some "in-between" with interpolation artifacts, it normally isn't as noticeable.

[bobt]

Dropping in the Ocean ???? ..... New meaning to Billy's name eh ! ( get it ? Billy Ocean ???)

Opening it to see how it works ,....... We never really grow up do we

Unfortunately it was attached to my first NH1 when it happened, disc still works, I have a beautiful paperweight now,but two more that I am way more careful with.

As to opening it up, I'm a mechanic I have to know how it works, when I was a kid clocks were never safe.

Bob

[Sony_Fan]

heavily scratched CDs and things like that can degrade the sound of the disc because the cd player itself interpolates (guesses) the missing data. But it's not something the average user can pick up, normally.

I believe MiniDisc works the same way.

What matters with mediums like MiniDisc is the chemical stability of the medium with regards to writes/rewrites (and of course wear from the magnetic head, which actually touches the disc). All these things add up over many cycles.

Digital or analogue, both cd and cassette (and md) are still reliant - in the end - on old-fashioned chemistry and the chemical properties of their mediums (and hardware) in doing what they do. Degradation with digital just has different characteristics (ie. not normally noticeable, or totally noticeable). Though there is some "in-between" with interpolation artifacts, it normally isn't as noticeable.

Well, what I do sometimes with minidiscs that I have used over and over again, I do full erase of the disc. I put the disc in my Hi-MD player and disconnect the earphones/mics and let it record in PCM 'til the end. That way, there's a huge blank track on the disc. This assures that the contents have been completely erased. Unlike the Format feature, which only erases the table of contents. So by doing a full erase, it's almose like having a blank "virgin" minidisc. Then I use the erase/format feature on the unit to erase the table of contents on the disc and I record/transfer music in Hi-SP or SP (optical in) and the music seems to sound more crisp and sharp.

Edited August 5, 2007 by Chris G

[raintheory]

Think of it this way...

Data is stored on the hard drive of your computer much the same way that it is on MiniDisc (as 1's & 0's... Digital Data, it's up to the D/A converter in the MD unit to transform the data to sound). Do mp3's sound better when played from a new hard drive vs an old one?

When you delete something from your computer it simply deletes the reference to the data, not the actual data itself, same with formatting a MiniDisc. I can state with a high degree of certainty that recording a blank PCM file to your disc before formatting will only decrease the lifespan of the disc (and your unit), not affect the sound quality of the consecutive recording(s).

If you'd like to run some actual tests to confirm, you can use RightMark Audio Analyzer to compare the same recording on a new -vs- used disc: http://audio.rightmark.org/index_new.shtml

Edited August 5, 2007 by raintheory

[pata2001]

... and the music seems to sound more crisp and sharp.

[sarcasm]Why the hassle? I used my sharpie, wrote "Bose" on my HiMD blank, and it automatically sounds crystal crisp. If I used an actual cut-out "Bose" logo, it will increase the bass definition. [/sarcasm]

[Sony_Fan]

Think of it this way...

Data is stored on the hard drive of your computer much the same way that it is on MiniDisc (as 1's & 0's... Digital Data, it's up to the D/A converter in the MD unit to transform the data to sound). Do mp3's sound better when played from a new hard drive vs an old one?

When you delete something from your computer it simply deletes the reference to the data, not the actual data itself, same with formatting a MiniDisc. I can state with a high degree of certainty that recording a blank PCM file to your disc before formatting will only decrease the lifespan of the disc (and your unit), not affect the sound quality of the consecutive recording(s).

If you'd like to run some actual tests to confirm, you can use RightMark Audio Analyzer to compare the same recording on a new -vs- used disc: http://audio.rightmark.org/index_new.shtml

No, they sound the same, but the writing head on a hardrive does not touch the surface. On MD, the writing head does touch the surface, therefore some wear/tear occurs. I can see why the recording head would eventually become useless. It would have been better if MD music/data was written using a laser instead of a magnetic head.

[raintheory]

No, they sound the same, but the writing head on a hardrive does not touch the surface. On MD, the writing head does touch the surface, therefore some wear/tear occurs. I can see why the recording head would eventually become useless. It would have been better if MD music/data was written using a laser instead of a magnetic head.

MiniDisc actually uses both the magnetic head and the laser to work.

As far as the claim I have seen here a few times regarding the magnetic head actually touching the disc (regarding portable units), I haven't been able to find any references to back that up... If you've ever looked inside a hard drive it certainly looks like the heads touch, but in reality they don't (due to air flow, Bernoulli's principle I believe). This could be the same with MiniDisc, and in my mind warrants further investigation. I'd like to know for sure, I've opened up my fair share of MiniDisc units and don't ever remember seeing this phenomenon.

Edited August 5, 2007 by raintheory

[tekdroid]

MiniDisc actually uses both the magnetic head and the laser to work.

As far as the claim I have seen here a few times regarding the magnetic head actually touching the disc (regarding portable units), I haven't been able to find any references to back that up... If you've ever looked inside a hard drive it certainly looks like the heads touch, but in reality they don't (due to air flow, Bernoulli's principle I believe). This could be the same with MiniDisc, and in my mind warrants further investigation. I'd like to know for sure, I've opened up my fair share of MiniDisc units and don't ever remember seeing this phenomenon.

when MiniDisc was intro'd, this was mentioned in countless articles talking about the technology. The head had to be low friction and touching the disc was necessary for the tolerances involved. Not sure why it isn't mentioned as explicitly nowadays. As far as I'm concerned it's fact.

[caddydaddyfleetwood]

Well, what I do sometimes with minidiscs that I have used over and over again, I do full erase of the disc. I put the disc in my Hi-MD player and disconnect the earphones/mics and let it record in PCM 'til the end. That way, there's a huge blank track on the disc. This assures that the contents have been completely erased. Unlike the Format feature, which only erases the table of contents. So by doing a full erase, it's almose like having a blank "virgin" minidisc. Then I use the erase/format feature on the unit to erase the table of contents on the disc and I record/transfer music in Hi-SP or SP (optical in) and the music seems to sound more crisp and sharp.

on my first MD player it had the optical in, and i used to use my PS2 to record my MD's although it took however long the cd was, it always sounded better, now i use the net md thing and its okay, but since i compress my files to maximize my space, they dont sound nearley as good...

[superboy]

Does anyone here notice with their HiMD discs that as you format and reload content on the disc, it loses a little bit of capacity? I think my HiMD discs start off around 940 MB of space, and I'm slowly dipping around 920 and below now. Am I formatting wrong? Should I erase instead of format or something like that?

Does anyone here notice with their HiMD discs that as you format and reload content on the disc, it loses a little bit of capacity? I think my HiMD discs start off around 940 MB of space, and I'm slowly dipping around 920 and below now. Am I formatting wrong? Should I erase instead of format or something like that?

[Sony_Fan]

Does anyone here notice with their HiMD discs that as you format and reload content on the disc, it loses a little bit of capacity? I think my HiMD discs start off around 940 MB of space, and I'm slowly dipping around 920 and below now. Am I formatting wrong? Should I erase instead of format or something like that?

Does anyone here notice with their HiMD discs that as you format and reload content on the disc, it loses a little bit of capacity? I think my HiMD discs start off around 940 MB of space, and I'm slowly dipping around 920 and below now. Am I formatting wrong? Should I erase instead of format or something like that?

Do a full format using windows explorer. Right click on the USB drive in windows, and choose Format, uncheck quick format and click start. This will erase everything on the disc, all content including table of contents. Then formatted to Hi-MD with sonic stage or the unit itself. I've done this several times and I get a consistent 964MB free space on a blank 1GB disc.

[superboy]

Thanks Chris, I will try that. Will that accomplish the same thing as erasing the disc from the options on the mindisc unit? Someone said that if I just format, it clears the TOC but doesn't necessarily wipe out the disc. I heard that if you erase, you get the entire disc back as if it were a fresh disc. Am I understanding this correctly?