More MD Recorders: Sharp MD-MT 180 & Sony MZ-N 510

Finally! A long time has passed since my last article and while I´m sorry for what appeared to be apparent inactivity I actually have been very busy. I´ve spent these two months with several 'new' MiniDisc recorders, more measurments regarding ATRAC... and of course: having fun! Yes, I may appear to be the most gadget-centric geek in the history of blogging  (don´t you sometimes have the feeling that it´s healthy to be delusional?) while in reality I tend to be an outgoing person with an occasionally quite egocentric attitude (WHO? MEEEE? - imagine Cher here). Guys, here in Germany it finally happened to be... Summer! The Sun was shining, the boys were wearing short pants revealing everything of secondary importance... well, if there was anything to be revealed... the flowers were smelling, the air was warm and people seemed to be relaxed which isn´t an easy feat for us stubborn Germans. Nevermind. I would like to talk about two MiniDisc recorders I purchased on eBay. One is the Sharp MD-MT 180 and the other is the Sony MZ-N 510, both purchased in used but decent condition. I also bought a Sony MZ-N1 - I would love to talk about that one too but one week after receiving this lovely looking MD Recorder it broke, I suspect either the ribbon cable to the magnetic writing head or the laser responsible for its malfunction. Both seem to be common flaws with this little machine; the ribbon cable could have been repaired by myself with a bit of soldering but the laser is unsalvageble. It is a MiniDisc recorder to be avoided at all costs, it just is too unreliable for its own good. Even if it would be well sounding (it was). The MZ-N 510 doesn´t have these reliability problems and neither does the Sharp.

The Sharp MD-MT 180 - ugly, don´t you think? Not even Instagram-like 'art' can hide this

Sony MZ-N 510 - my second NetMD Recorder and IMO with a superior design compared to the recorder above

I´ve acquired the Sharp because several people all over the net are talking about their high sound quality. According to them Sharp MD Recorders generally have a well rendered bass response and good technical qualities. Sharp themselves claimed their implementation of the ATRAC coding scheme to be the best on the market, superior to the one Sony originally designed and improved over the years. Why would Sony allow other companies to produce their own versions of ATRAC? Because when they were releasing the MD format to the market in 1992 Sony had hoped to increase market penetration by allowing competing manufacturers to use their patents without actually having to pay fees for them. In the end, three other companies apart from Sony produced their own ATRAC implementations: Sharp, Pioneer and Matsushita (Technics, Panasonic). That situation inadvertently led to different and confusing ATRAC version numbers: while the Sony MZ-N 510 uses ATRAC DSP Type-S, the Sharp MD-MT 180 uses Sharp-ATRAC 6.0. Both ATRAC versions feature full 24 Bit processing (-> WideBitStream), enabling them to capture audio material with a resolution higher than that of the Compact Disc in spite of using a lossy encoding scheme. In order to find out how the Sharp ATRAC performs and if it would offer an improved way of encoding music I decided to buy it. The Sony MZ-N 510 on the other hand was purchased to have a look at the last ATRAC version to be released by Sony and to find out how well the NetMD feature performs. When ATRAC DSP Type-R (Type-S is the same) was released to the market Sony claimed that an additional encoding step resulted in less distortions when compared to the predecessor ATRAC 4.5. According to them they achieved it by doubling the processing power of the ATRAC chip. Well, to me this sounds an awful lot like a flowery description of a classic 2-pass-enconding, yet how Sony would achieve this in combination with on-the-fly encoding is baffling to me. Anyway, let´s see how it performs (playback necessary for the charts below was performed by the Kenwood DM-5090 through its digital, optical output):

Sharp ATRAC 6.0

Sony ATRAC DSP Type-S (the same as ATRAC DSP Type-R)

The Noise Level of -400.0 dB (A) of ATRAC 6.0 is probably achieved by the Sharp muting its input, this muting can obviously be done to a specific channel only which in turn leads to the phenomenal Stereo Crosstalk performance. Sony's ATRAC obviously treats both channels as one entity; it also doesn´t mute its input. THD + Noise and IMD at 10 kHz seem to be much better compared to the Sony while IMD + Noise seem worse. The chart below shows another row of measurments (four seperate measurments for each ATRAC version combined into one respective output chart). Below that you´ll also find some graphs explaining some of the measurments:

Comparison of Sony ATRAC 4.0, DSP Type-S and Sharp ATRAC 6.0

Frequency response ((dB) A) of the several implementations

THD + Noise comparison

IMD comparison

As you can see on the frequency response graph Sharp's ATRAC does something odd to the high frequency spectrum. Further examination of the encoded multispectrum test signal reveals that high frequencies are not really "there", instead they have been replaced by quantization noise. Sony's ATRAC probably behaves the same even though it appears to be concealed better there. The THD + Noise graph also shows that the Sharp ATRAC has problems with distortions around 2.000 kHz, a frequency area where our ear is very sensitive. Even Sony's ATRAC 4.0 exhibits slightly lower distortions there, ATRAC DSP Type-S faires best with the lowest amount of distortion. On the other hand the Sharp ATRAC has the lowest low frequency distortions. The intermodulation distortion graph shows - just like the frequency response - some odd high frequency behaviour of the Sharp ATRAC again. With the Sonys the overall noisefloor is higher but much more consistent throughout. With them though one thing is crystal clear: the attention of the encoding scheme was shifted to frequencies more sensitive to our ears instead of higher frequencies when one observes measurment differences from ATRAC 4.0 to ATRAC DSP Type-S. While ATRAC 4.0 encodes high frequencies with less noise it partly fails at lower frequencies, with ATRAC DSP Type-S it´s the other way around. Sharp's ATRAC 6.0 obviously attempts to do the same but fails; high frequencies show odd behaviour while frequencies important to our ear show higher distortions as well. Which is evidenced with music too:

"Lady in the Water", Sharp ATRAC 6.0

"Lady in the Water", Sony ATRAC DSP Type-S

As you can see above Sharp's ATRAC 6.0 only rarely encodes frequencies beyond 16.000 Hz, it behaves exactly like mp3. The track above is only one example, I´ve seen it with every single track I´ve recorded with it. With every track the frequency amount or content above 16.000 Hz seems to be irrelevant to Sharp's ATRAC. Sony's ATRAC DSP Type-S on the other hand manages to encode content up to 18.000 Hz, sometimes up to 19.000 Hz and occasionally even up to 20.000 Hz. BTW, before I made any measurments at all I started with my examinations by listening to the respective recordings, then I took the step of looking at them while measurments were the last thing I did and only confirmed what I was suspecting: Sharp's ATRAC 6.0 isn´t very good. From what I was seeing above I expected ATRAC 6.0 to measure perfectly at frequencies important to our ear, the missing content above 16.000 Hz led me to expect an attention-shifting effect not unlike the one I experienced when going from ATRAC 4.0 to DSP Type-S.

Sharp MD-MT 180 - disappointing performance

Sony MZ-N 510 - NetMD equipped and a reliable recorder

How do these different ATRAC implementations sound? Do they sound at all, something they shouldn´t do? Yes, they do. Recordings made with the Sharp MD-MT 180 always sound flat and "grey", Sharp ATRAC encoded music played back on for example the Sony MZ-R 30 or the Sony MZ-R 900 somehow seem to loose their amount of reverb, turning them into something uninvolving without much differentiation. Recordings made with the Sony MZ-N 510 on the other hand sound... well, pristine and very much transparent. During the last two months I haven´t been able to trip the ATRAC DSP Type-S into making any errors whatsoever. Despite using lossy compression the latest Sony ATRAC seems to be fully transparent, I´m unable to discern any difference between a 24 Bit .wav original and its ATRAC DSP Type-S encoded counterpart. Sony's ATRAC 4.0 in comparison softens the sound somewhat and can be prone to compression errors. The new James Horner score "The Amazing Spider Man" for example contains two tracks with fingersnapping and ATRAC 4.0 fails very audible at encoding them, creating strange sounding compression artifacts. ATRAC DSP Type-S doesn´t have any problems at all, recordings made with it are just perfect. It doesn´t matter if they are played back by the MZ-R 30, the MZ-R 900 or the Kenwood DM-5090. BTW, I double checked the transparency of ATRAC DSP Type-S with recordings made with the ATRAC DSP Type-R, the direct predecessor. For that I used the (now repaired) Sony MZ-R 501 from my boyfriend which he had in his posession for nearly ten years (now it´s mine ;)). ATRAC DSP Type-R is very much the same encoder, only the ATRAC3 decoding part is not as powerful and error resistant as the one contained in ATRAC DSP Type-S. Not surprisingly, both measured and sounded the same.

Sharp MD-MT 180 close-up

Sony MZ-N 510 close-up

But how do they sound with their headphone outputs during playback? Connecting my Sennheiser HD-448 to these outputs (they both lack line-outs) and using Sony-encoded music the Sharp easily beats the Sony. For one, the Sharp's output is considerably louder (boasting 10 mW into 16 Ohms compared to 5 mW for the Sony) and it´s also the more neutral output. The Sony's output isn´t very good I´m afraid, bass is too strong and treble seems muted while the stage is constricted. It appears to be better suited for recording and not so much for playback, considering that you - like me - have the same desire for neutrality. Attention: the playback quality for both gadgets is more or less caused by their built-in headphone amps and has nothing to do with D/A converters, ATRAC decoders or anything else. One thing however is for sure: Neither the Sharp nor the Sony are able to match the sound of the MZ-R 30 or the MZ-R 900 through their line-outs. While the MZ-R 30 does indeed colour the sound slightly the R-900 is one of the most neutral portable players ever released - even though both of them are clearly superior playback devices. You may remember that I´ve written during my last MD article that I would like to have a look at ATRAC3 performance... oh, you are confused by another ATRAC version? Yes, it´s an easy mistake to make so let me explain: ATRAC3 was released in 1999 together with the MDLP (MiniDisc LongPlay) addition to the MD format and shouldn´t be confused with any of the aformentionend ATRAC versions. Data rates for MDLP were 132 kBit/s (LP2) and 64 kBit/s (LP4) and with these you could double or quadruple recording time. But even when boasting the same name as the old ATRAC these two encoding schemes doesn´t have very much in common... and it´s something that´s very audible: LP2 sounds decent but is no match against more modern implementations of mp3, ogg, wma or against the first ATRAC. LP4 is just one thing in my opinion: useless, more recent codecs like AAC are much better suited for a bitrate this low.

... and the Winner is the Sony MZ-N 510

If this would be a classic contest between two contestants the MZ-N 510 would be the winner. It´s a very reliable recorder, with transparent and pristine recording quality. Playback quality on the other hand isn´t that good. Its NetMD feature is only suited for one thing: conveniently titling an MD. For music it´s almost worthless simply because the achievable sound quality suffers so much. You can imagine how I´ve used my several MD recorders during the last two months: the MZ-N 510 for recording, adding or substracting track marks and for titling an MD while either the MZ-R 30 or the MZ-R 900 were used for playback in combination with my FiiO. Seems complicated? Yes, it is. It would be much easier to just use my Sansa Clip+ for it will upload music much faster (with MD recorders I have to record it instead in real-time), is much smaller and supports more modern encoding schemes. But no, I won´t do it just because it doesn´t sound as well as the Sony MZ-R 30 and is not even close to the sonic perfection of the Sony MZ-R 900. Nevermind, should you consider buying a used MD recorder go for the MZ-N 510 - but use it as a flawless recording device only. Avoid the Sharp for it will inadvertently colour recordings while at the same time won´t encode as well as the Sony.

Last update: 03.09.2012