Stationary ATRAC vs. portable ATRAC - differences?

[MDietrich]

Introduction

First of all, a HUGE thanks to member punkrockaddict, without him this post wouldn´t have been possible.

Attention: the following post will be tech-heavy, so if you don´t know how to read graphs or don´t have time to read explanations, skip it until you have the time. Should you consider yourself tech-illiterate, don´t despair. I will try to make all of this easy to read and understand. If you have some questions, please don´t hesitate and ask. It´s a simple as that: there are no dumb questions. If you have a question it just means that I sucked at explaining.

Have you ever seen following sentences in the manual of portable Type-R equipped recorders: "Type-R" is a high-level Sony-specification used in the Digital Signal Processor (DSP), which is heart of the MiniDisc sound. This technology gives the MiniDisc recorder twice the signal processing capability as previous MiniDisc Walkman models, producing a sound quality close to that of MiniDisc decks." (Sony MZ-R 909 manual, page 30)

I´ve underlined the important part. It suggests that stationary MD decks have a higher encoding quality compared to portable devices. Since I don´t own an MD deck I could never test this myself. But then user Sony_Fan asked the same question in the thread The result was that punkrockaddict offered to record a testsignal I´ve sent him via email to his MDS-JB930. His MD arrived today and I´ve compared its results to two of my portable MD recorders.

But before I start with measurements I´d like to offer an explanation for possible differences between stationary ATRAC and portable ATRAC. As you all know, ATRAC was developed so that portable MD recorders could work with it without drawing too much power from the battery. You see, higher encoding quality = higher processing power = higher power demands. A battery that is drained fast on a portable unit isn´t very convenient and so I thought that Sony might have compromised encoding quality to conserve power. On stationary decks with their unlimited power supply they could allow the ATRAC encoder to go with full force, making no compromises.

All of this is perfectly possible since ATRAC is an asymmetrical codec. It needs much power during encoding, but only a small fraction when decoding. This means that it´s perfectly possible for a portable recorder to have a worse encoding quality than a stationary decks, even when both are using the same ATRAC version.

BTW, all the graphs, explanations and measurements have nothing to do with the A/D or D/A-converters. This post isn´t written to show how good or bad the respective MD units sound on their analogue outputs.

Measurements

Test equipment:

Sony MDS-JB930QS (punkrockaddict)

Sony MZ-R 909 (my own)

Sony MZ-N 510 (my own)

Testsignal:

32 bit floating point, 44.1 kHz, generated by RMAA

Signalflow to MD: playback with foobar2000, delivered with digital S/PDIF-cables to the respective MD recorders.

Signalflow to PC: playback with Kenwood DP-5090, deliverd with digital S/PDIF-cables to the X-Fi HD USB.

Resulting signal: full 24 bit 44.1 kHz

RMAA generated table, showing differences between the three recorders

MDS-JB930QS ATRAC Type-R performance with RMAA quality assessments

MZ-R 909 ATRAC Type-R performance with RMAA quality assessments

You can see, that both units measure well considering that they use an ancient lossy codec. However, in some parts the home deck measures even better. Much better in fact. Let´s have a look at some detailed graphs:

Dynamic range, MDS-JB930QS

Dynamic range, MZ-R 909

Both recorders record and transmit a true 24 bit signal. But as you can see on the graph depicting the MDS-JB930QS, the stationary ATRAC IC is way superior at keeping quantization noise at bay (which looks like a higher noisefloor on the MZ-R909 graph).

Total harmonic distortions, MDS-JB930QS

Total harmonic distortions, MZ-R 909

The graphs showing the total harmonic distortions may not look like much. But you can still see that the MDS-JB930 is better a supressing distortions. Distortions are in this case errors caused by the compression.

Phase response, MDS-JB930QS

Phase response, MZ-R 909

Now the phase response is especially interesting. Every MD recorder I´ve measured until today (with the exception of a Sharp-unit) has shown the phase response you can see on the MZ-R909 derived graph. Portable ATRAC version introduce a phase error to the signal. What exactly is the phase response? Well, have you ever connected a loudspeaker wrong to your amplifier (red connector on the speaker connected to the black connector on the amp)? And have you then wondered about some very strange sound?

That is a classical phase error. In that common case you have fully inverted the phase which means that the loudspeaker membranes will be pulled instead of pushed. Not so easy are the phase errors you can see above. You see, the MZ-R 909 ATRAC inverts the phase at high frequencies only. It means that membranes will be pulled only at high frequencies; lower frequencies will not. Science is still not very clear about the audibility of phase errors, I however believe that they are responsible for sonic differences between different units.

Portable ATRAC introduces phase errors that aren´t supposed to be there, stationary ATRAC does not.

Conclusion

It´s simple: Stationary MD decks record with better quality than portable MD recorders, even if they are equipped with the same ATRAC version. Reasons are explained above. For everyone owning a stationary Type-R deck... consider yourself lucky, for you have the best possible ATRAC quality. For me... crap... it means I have to get myself a deck!

P.S.: I cannot repeat this with any recorder equipped with ATRAC 4.0/4.5. The Kenwood DP-5090 and Sony MZ-R 30/50/55/37 all have exactly the same ATRAC performance. This means, Sony introduced the intentionally compromised, portable ATRAC IC with ATRAC DSP Type-R.

[punkrockaddict]

Should i be surprised? Although i didn´t ever notice the note in the manual ( because i don´t read them ) i did not think this would have happen.

But one thing is unclear to me. If i record with the DR580 connected to its ac power adapter is the recording also worse compared to the Deck?

I like playing with these stationary portables and i think i did record some albums this way.

But most of all i record PCM when using portables..

But this is as exciting as it seems .. nice to know there´s so much difference.Thanks for your great job

[MDietrich]

Should i be surprised? Although i didn´t ever notice the note in the manual ( because i don´t read them ) i did not think this would have happen.

But one thing is unclear to me. If i record with the DR580 connected to its ac power adapter is the recording also worse compared to the Deck?

I like playing with these stationary portables and i think i did record some albums this way.

But most of all i record PCM when using portables..

But this is as exciting as it seems .. nice to know there´s so much difference.Thanks for your great job

No, thank you!

Yes, it doesn´t matter if you use the power adapter for the portables, the DSP Type-R equipped models all have this performance. For the measurements above they were all powered by their adapter and not by the battery.

[Sony_Fan]

Ok, so that settles it! I think I need an MD recorder deck too. But now, can the human ear tell the difference between the portable and deck recordings?

[MDietrich]

Ok, so that settles it! I think I need an MD recorder deck too. But now, can the human ear tell the difference between the portable and deck recordings?

HA! That´s the most important question. And you´re the first to ask... I thought "When is someone discovering that I didn´t answered this question?" Congratulations!

Well, the answer is that I don´t know. I´m watching several MD decks on eBay right now in the hope of getting one so that I can try myself.

If I´m extrapolating from the measurements, recording with a stationary recorder might help dynamics (because non-linear phase errors like the ones coming from the portables create transient problems -> dynamic impairment). There also might be less artifacts to be observed, but that I don´t know.

[Sony_Fan]

HA! That´s the most important question. And you´re the first to ask... I thought "When is someone discovering that I didn´t answered this question?" Congratulations!

Well, the answer is that I don´t know. I´m watching several MD decks on eBay right now in the hope of getting one so that I can try myself.

If I´m extrapolating from the measurements, recording with a stationary recorder might help dynamics (because non-linear phase errors like the ones coming from the portables create transient problems -> dynamic impairment). There also might be less artifacts to be observed, but that I don´t know.

Which stationary recorders have DSP Type-R? Or which of those is the cheapest?

I'm guessing that CD->MD DSP Type-R copy (on stationary deck) will still not sound better than pre-recorded MDs.

[MDietrich]

Which stationary recorders have DSP Type-R? Or which of those is the cheapest?

I'm guessing that CD->MD DSP Type-R copy (on stationary deck) will still not sound better than pre-recorded MDs.

Well, the cheapest one on eBay that also has an optical output (important to me) would be the MDS-JE 530. The JE 640 is still quite expensive (don´t really know why)... and the QS-models are of course way too expensive considering their age. I won´t even mention the ES-models...

[sfbp]

You can easily convert a 440 to a 640 by adding optical out. Parts are about $3. They use the same service manual!

[MDietrich]

You can easily convert a 440 to a 640 by adding optical out. Parts are about $3. They use the same service manual!

Yeah, I´ve read the guide. But I´m not very good at soldering so I´m a bit afraid to do it

[sfbp]

Not even sure you have to solder anything at least on the circuit board. The point being that if you use the 5V part then you can use Vcc (5V) and the wires are all on the connector to the satellite board. CN103, so they can be made to push fit. Sure, the LED itself you have to solder, but you can afford to waste one or two of those if you mess up. You don't even have to worry about mounting it, I used duct tape.

[Sony_Fan]

HA! That´s the most important question. And you´re the first to ask... I thought "When is someone discovering that I didn´t answered this question?" Congratulations!

Well, the answer is that I don´t know. I´m watching several MD decks on eBay right now in the hope of getting one so that I can try myself.

If I´m extrapolating from the measurements, recording with a stationary recorder might help dynamics (because non-linear phase errors like the ones coming from the portables create transient problems -> dynamic impairment). There also might be less artifacts to be observed, but that I don´t know.

I'm starting to wonder if stationary Hi-MD recorders will record better than the portable Hi-MD recorders. Probably yes!

Also, how necessary is the remote control for MD decks? I've noticed on ebay many decks don't come with the remote.

[philippeb]

Also, how necessary is the remote control for MD decks? I've noticed on ebay many decks don't come with the remote.

I own many Sony decks, and I do not use the remotes. I much prefer interacting physically with the decks. A few features cannot be accessed without remote, though, typically REC-IT or DATE RECORDED.

[Sony_Fan]

I own many Sony decks, and I do not use the remotes. I much prefer interacting physically with the decks. A few features cannot be accessed without remote, though, typically REC-IT or DATE RECORDED.

I just want to be able to do Sync recording and adjust the recording volume. Can this be done without the remote?

[punkrockaddict]

if a Hi-md Deck would behave the same way it would only affect Hi-Md modes ( Hi-Sp, Hi-LP)

And i never recorded something in these codecs.Only PCM of course. So that wouldn´t be that important, at least to me.

And i lack a Hi-Md Deck too

Did anybody try to listen to the difference Deck type-r and portable type-r ?

I didn´t have the time till now.Think i´ll check at the weekend.

I just want to be able to do Sync recording and adjust the recording volume. Can this be done without the remote?

Afaik not. But you could get any remote from sony minidisc decks and use instead of the roiginal one. they do work.. just not the special featured buttons as theyx were only on the original remotes.

[Another MD fanatic]

Another fascinating article MDietrich, as always. I must say though I certainly doubt if my ears would detect these differences.

By the way, have you ever tried recording any pure sine waves to MD? I've done it and everything was ok until it got up to 10 kHz, then it all went a bit strange. Try it and see what you think.

And to Sony_Fan - I find the biggest advantage of using a remote is simply in titling! This can be done in a fraction of the time it takes on a portable and can be done while the deck is still recording.

[Sony_Fan]

Another fascinating article MDietrich, as always. I must say though I certainly doubt if my ears would detect these differences.

By the way, have you ever tried recording any pure sine waves to MD? I've done it and everything was ok until it got up to 10 kHz, then it all went a bit strange. Try it and see what you think.

And to Sony_Fan - I find the biggest advantage of using a remote is simply in titling! This can be done in a fraction of the time it takes on a portable and can be done while the deck is still recording.

Thanks. So I can do Sync CD recording and adjust recording level without the remote? For titling, I just put the disc into a NetMD and write the titles in using MD Simple Burner on my computer.

[philippeb]

So I can do Sync CD recording and adjust recording level without the remote?

Yes you can, on all Sony decks I know. Titling is also possible on the deck, without remote.

[MDietrich]

I just want to be able to do Sync recording and adjust the recording volume. Can this be done without the remote?

More than 10 years ago I owned the MDS-JE530, I could deal with it without using the remote. It´s not very convenient, you have to use the 'Menu'-button and the jog dial a lot. But it works.

Another fascinating article MDietrich, as always. I must say though I certainly doubt if my ears would detect these differences.

By the way, have you ever tried recording any pure sine waves to MD? I've done it and everything was ok until it got up to 10 kHz, then it all went a bit strange. Try it and see what you think.

And to Sony_Fan - I find the biggest advantage of using a remote is simply in titling! This can be done in a fraction of the time it takes on a portable and can be done while the deck is still recording.

Yes, even simple sine waves are a challenge for the ATRAC codec when it comes to treble frequencies. Since we can´t hear those frequencies very well, ATRAC takes away more bits there, leaving only quantization noise which then looks strange.

And titling? Nothing can beat a NetMD recorder. I always title using NetMD. Record a disc with any recorder, then title it using NetMD. Very comfortable.

[PhilippeC]

There is MD technical Nobel price involve before Xmas ? Even sfbp Stephen is distanced except with in the overall technical price. I have noticed the first weeks a huge difference in sound (dynamics) between my JB980 and my portable units - all connected to my audiophile system - when listening. Don't remember with witch unis - deck or portable - those listening tests irecordings (hope you can understand me ) has been done. I am also not able to remember audible differences in high frequencies at the time, just a huge feeling of getting more dynamics. Maybe it is time to make my own tests. Not with my RH1 (NH900 + 2 RH1 in Europe), but I have here a NH700.

Explain why MDietrich said that he was on his way to buy a deck !

Do you explain already in a post your methodology MDietrich, specialy your getting measurements & graphs protocol ?

[Sony_Fan]

Yes you can, on all Sony decks I know. Titling is also possible on the deck, without remote.

This is the MDS-JE440. Any good?

http://www.ebay.com/itm/190917332785?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

[MDietrich]

There is MD technical Nobel price involve before Xmas ? Even sfbp Stephen is distanced except with in the overall technical price. I have noticed the first weeks a huge difference in sound (dynamics) between my JB980 and my portable units - all connected to my audiophile system - when listening. Don't remember with witch unis - deck or portable - those listening tests irecordings (hope you can understand me ) has been done. I am also not able to remember audible differences in high frequencies at the time, just a huge feeling of getting more dynamics. Maybe it is time to make my own tests. Not with my RH1 (NH900 + 2 RH1 in Europe), but I have here a NH700.

Explain why MDietrich said that he was on his way to buy a deck !

Do you explain already in a post your methodology MDietrich, specialy your getting measurements & graphs protocol ?

In fact, I don´t understand everything

But I´ll try to answer. My methodology involves RMAA. It´s a little, free program where I can create measurement signals, pass them through the device I want to test and then let the program analyze the output. It can be used for almost anything. I use it only so that what I hear is confirmed (or not) by the measurements.

The rest (how I recorded those signals and got them back to the PC) was explained in the first post.

When you say you compared the JB980 to your portable machines, do you mean that you connected all of them with their RCA output? Because that´s not what punkrockaddict and I did. We kept any signal digital all the time. We didn´t want to know how some MD recorder is sounding, we wanted to know if the ATRAC differs.

This is the MDS-JE440. Any good?

http://www.ebay.com/itm/190917332785?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

If I might chime in... I noticed that the seller doesn´t write anything about recording, he only mentions working playback. I can´t help it, but I find this suspicious. And admittedly, the deck looks pretty beaten.

[PhilippeC]

When you say you compared the JB980 to your portable machines, do you mean that you connected all of them with their RCA output? Because that´s not what punkrockaddict and I did. We kept any signal digital all the time. We didn´t want to know how some MD recorder is sounding, we wanted to know if the ATRAC differs.

If I might chime in... I noticed that the seller doesn´t write anything about recording, he only mentions working playback. I can´t help it, but I find this suspicious. And admittedly, the deck looks pretty beaten.

How can you keep the signal digital all the time with a portable unit witch don't have an optical out ? Do you use a RH1 to upload the recorded signal in the PC / RMAA ? Or, do you use the optical out of the deck to the PC / RMAA to make the difference between portable and (the same) deck recording ?

[PhilippeC]

I also suppose that the computer need to have a very good audio card. My inboard sound card in my laptop - Realteck "High Definition" Audio - is not as good (and user friendly) as my PCI Creative Platinium X-Fi (actually waiting outside my out of order desktop). I also have a Hercules Muse LT external audio card.

Edit : after a listening test, that Muse LT is not better than my inboard card.

[philippeb]

This is the MDS-JE440. Any good?

http://www.ebay.com/itm/190917332785?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

I do not know this deck. I have read the user manual and found that MUSIC/CD SYNC can only be activated from the remote.

[PhilippeC]

I own many Sony decks, and I do not use the remotes. I much prefer interacting physically with the decks. A few features cannot be accessed without remote, though, typically REC-IT or DATE RECORDED.

OK when you record in real time, just like old time with K7 decks... but during listening, if you have a black desk in a dark room - and some presbyopia - you will hurry to find a remote (I even got a second one for JB980, just in case).

[MDietrich]

How can you keep the signal digital all the time with a portable unit witch don't have an optical out ? Do you use a RH1 to upload the recorded signal in the PC / RMAA ? Or, do you use the optical out of the deck to the PC / RMAA to make the difference between portable and (the same) deck recording ?

Punkrockaddict recorded his test signal digitally with the MDS-JB930. The digital signal was provided by his Creative Soundblaster Audigy 4. He then packed his MD into an envelope and sent it to me via mail.

I recorded my test signal digitally with the MZ-R 909 onto the same disc. The digital signal was provided by my Creative Soundblaster X-Fi HD USB.

In both cases the signal was bit-perfect, meaning both soundcards didn´t alter it.

After all signal were recorded to MD I played them back with the Kenwood DM-5090 digitally. It has optical outs, my Soundblaster X-Fi HD USB has optical ins. The Kenwood gives out a digital 20 bit signal which the X-Fi HD USB is able to record unaltered.

That way I was able to compare the pure ATRAC performance.

[PhilippeC]

OK, I thought well, you used the deck optical out.

I am sorry not to be able to use my Creative X-Fi Platinium sound card.

Just for fun, I can run these tests anyway, with my laptop.

JB980 vs MZ-N710(Net-MD), MZ-N510 (Net-MD), MZ-R55 (SP), MZ-R30 (SP)

[Sony_Fan]

How about a test comparing Sharp's 24-bit ATRAC units against Sony's ATRAC Type-R units? My understanding is that Sharp's ATRAC codec was a little different than Sony's.

[MDietrich]

How about a test comparing Sharp's 24-bit ATRAC units against Sony's ATRAC Type-R units? My understanding is that Sharp's ATRAC codec was a little different than Sony's.

Yes, it was. But Sharp did not disclose which units contained which ATRAC version. I have a Sharp MD-MT 180. Does it have Sharp ATRAC 6 or 7? I tested it and found it to be bad (comparing it against DSP Type-R). And what about the MD-MT 270? I own that one too - and it´s much better but not on the same level as the stationary Sony-ATRAC.

[Sony_Fan]

Yes, it was. But Sharp did not disclose which units contained which ATRAC version. I have a Sharp MD-MT 180. Does it have Sharp ATRAC 6 or 7? I tested it and found it to be bad (comparing it against DSP Type-R). And what about the MD-MT 270? I own that one too - and it´s much better but not on the same level as the stationary Sony-ATRAC.

So is it safe to say that all DSP Type-R minidisc decks will record the same, in terms of sound quality (SP 292kbps). An expensive JB or ES model, will not record better than a lower level model like JE-440?

[MDietrich]

So is it safe to say that all DSP Type-R minidisc decks will record the same, in terms of sound quality (SP 292kbps). An expensive JB or ES model, will not record better than a lower level model like JE-440?

Ha! Again, a very good question. I hope that an ES deck is not better than a lower level model... but Sony, who always was very conscious about price-related quality differences, could very well have tweaked the ATRAC IC further. In reality though... I´ll never own an ES deck. Prices are way too high and clearly not justified, so I won´t know and have to work with the average-joe-models instead

[bluecrab]

I just assume good recording quality in minidisc decks. I have had both low- and high-end models and although I'm not certain about differences in recording quality, I will state emphatically (if subjectively) that the JA/JB series sound noticeably better on playback than do the JEs (as well as the Pioneer MJ-D508, the only non-Sony deck I have ever owned). It's important to me because I mostly do playback through a decent separate-component system - two of them, really. At the moment I am playing an MD that I recorded on who-knows-what deck on an JA20ES that I got at a pretty good price on eBay, at a time when you could still sometimes find the more desirable decks at relatively reasonable prices. The SQ this unit produces is, for me, well worth what I paid for it. Glad I was able to grab it when I could!

[PhilippeC]

phamcu (who sell and repair MD decks) told me that the JB980 is much better than his JE780 (both MDLP type S).

[PogoPogoPogo]

Excellent topic here, I always have wondered if there was a real (measureable) difference between recording realtime on portables and decks.

It would also be interesting to see if there are measurable differences between recording LP2 on a deck/portable and LP2 via NetMD on a portable; when I record LP2 tracks that flow into each other on my JE480 deck (optical in), it's always smooth and gapless. However, I'm pretty sure gapless track flow can't be achieved via NetMD. This might suggest that the NetMD recording process slices just a tad more detail off hence the loss of that all important micro second for seamless track transition?

However, as mentioned in an earlier post, the most important thing to decide of course before leaping onto Ebay to purchase a deck is if one truly can make out a discernable audible difference between recordings made on deck and portable! I've not tested myself, but i'm pretty sure I'd find it difficult to tell a difference...

[MDietrich]

However, as mentioned in an earlier post, the most important thing to decide of course before leaping onto Ebay to purchase a deck is if one truly can make out a discernable audible difference between recordings made on deck and portable! I've not tested myself, but i'm pretty sure I'd find it difficult to tell a difference...

Exactly. I still have to get some decent deck to test that out myself. Right now I´m watching several, but it´ll take a while.

[yakovcs]

Thank you MDietrich for this topic

i have Technics SJ-MD100 deck , and all i can find about the Atrac version is this "24 bit Technics-ATRAC"

does anyone know what exact Atrac version it is? and the front panel it says 24Bit DSP processing... but i don't know is it type R or not

[Azureal]

The browser shows that my Sony JA-20ES dates to 5/1998 and it has a Type-R ATRAC.DSP, this was confirmed by opening the unit and DSP chip. I wonder if OEMs used Sony chips to implement the ATRAC compression/decompression, you could open it up and have a look. If you could find the DSP chip it may be easier to determine the version of ATRAC in the unit.

[MDietrich]

Thank you MDietrich for this topic

i have Technics SJ-MD100 deck , and all i can find about the Atrac version is this "24 bit Technics-ATRAC"

does anyone know what exact Atrac version it is? and the front panel it says 24Bit DSP processing... but i don't know is it type R or not

This is difficult. Technics / Panasonic never revealed what ATRAC version their own IC was built on. But it´s indeed their own IC, as shown by the service manual: http://www.minidisc.org/manuals/panasonic/service/panasonic_sjmd100-sup.pdf

I believe - this could be wrong - that they employed Sharp ATRAC 5.0 as a starting point and added their own set of algorithms to improve on it. But I don´t know exactly and for all I know this might be very wrong.

[yakovcs]

The browser shows that my Sony JA-20ES dates to 5/1998 and it has a Type-R ATRAC.DSP, this was confirmed by opening the unit and DSP chip. I wonder if OEMs used Sony chips to implement the ATRAC compression/decompression, you could open it up and have a look. If you could find the DSP chip it may be easier to determine the version of ATRAC in the unit.

Those chips i have inside , tried to google them but without any luck

[MDietrich]

Those chips i have inside , tried to google them but without any luck

The one up above is the ATRAC IC but just like you I couldn´t find any information.