MZ-NH600D: Impressions

[Abby Normal]

I picked up my second HiMD unit--an MZ-NH600D--for $51 USD shipped. It came with some buds, an empty plastic disc case that can hold 6 discs, and one sealed blank (another 80-minute Sony Gold). Initially I thought the sound quality was a bit flat compared to my RH1, but after I tweaked the equalizer settings it was almost indistinguishable. I expect this is going to be my workhorse playback unit so I can preserve the RH1 for things only the RH1 can do. I'll try to get the non-US version of this as well so I can have line-in, but I'd like to be patient and see if I can find a better deal than is presently available.

I may or may not post pictures. I think it's been done well enough already. See the equipment page linked below in my signature.

Edited July 3, 2009 by narp

[Avrin]

The unit sounds absolutely gorgeous with its great TOSHIBA analogue amp! It's one of the very few Hi-MD units (NH600D, NH600, NH700, and NHF800) that have it.

[sfbp]

Add another vote from moi for preferring the analogue amp. The EH70 seems better than the RH1, though both are digital. But the units you mention all perform well in my hands.

[Avrin]

BTW, a Canadian NH600D should sound different from a US one, since they have different capacitors and resistors at the amp input.

Edited July 3, 2009 by Avrin

[sfbp]

Does this go for the NH700 too?

And what does this mean? My 600D was acquired here, but I have no idea where original purchaser got it.

[Avrin]

The NH700/NHF800 is even more funny. The US version has the same output amp schematics as the US NH600D. The other versions have "Canadian" amp inputs. Plus, European versions (AEP, UK, EE) have their output signal passing through additional resistors (similar to the European NH600) to decrease output power.

See the attached diagram.

Edited July 4, 2009 by Avrin

[Abby Normal]

I remember reading the French version specs of some unit and while everyone else had 4-5 watts the French had 1. I guess they just have more sensitive hearing. Can someone confirm this?

[Deleted Member]

Deleted by author.

[Avrin]

Level limiting is required by law in France. And, since France is a member of the EU, all units sold in the EU are limited. Limiting is done in two parts:

1. Software limiting, set to compress sound above a certain level. May be disabled in service mode.

2. Hadware limiting, by resistors in the output circuit. May be removed by soldering (shortening the resistors).

Edited July 4, 2009 by Avrin

[Abby Normal]

The discussion on the FiiO E5 headphone amplifier was moved:

Moved to phones section here

(by Moderator)

Edited July 5, 2009 by narp

[A440]

Meanwhile, back at the NH600D....

If you really want to baby along your RH1, you can also use the NH600D to upload recordings in Hi-MD format (Hi-SP, Hi-LP, PCM) via SonicStage. So if you made recordings on the RH1, you could upload them with the NH600D.

Of course, you need the RH1 to upload old MD formats (SP, LP2, LP4) or for Mac compatibility.

[tekdroid]

The digital vs analogue amp is definitely down to taste and/or music and/or mood and/or ears.

I like the sounds of both, but I have to say I probably prefer the digital amp most of the time, the sound is more defined, less mushy and overblown, for want of a better description, while still being very balanced.

$51 is a good price. If I'm not totally mistaken, it's the buttons on the RH1 that fail... which is a shame. If you use the remote you should be good. I don't think there are any other unusual weaknesses, are there?

Edited July 5, 2009 by tekdroid

[Avrin]

The digital vs analogue amp is definitely down to taste and/or music and/or mood and/or ears.

It's quite simple. A digital amp is designed to work with headphones or an inexpensive power amp/loudspeaker combination, that have a relatively narrow frequency response, say, the standard 20 - 20,000 Hz. In this way the 1-bit signal form is brought close to a more-or-less analogue one. On the other hand, when a digital-amp unit is connected to a good Hi-Fi system, with a frequency response of, say, 10 - 80,000Hz, the signal form remains close to 1-bit, and sounds very dry and boring.

Edited July 5, 2009 by Avrin

[netmduser]

I picked up another one of these 600D today. What other audio devices is the toshiba ic352 amp used?

Edit: it looks like this ic is used in everything electronic tvs, dvds, microwave ovens.

Why did Sony use this in the 600D?

What is used in other MD models normally?

[jim.hoggarth]

I picked up another one of these 600D today. What other audio devices is the toshiba ic352 amp used?

Edit: it looks like this ic is used in everything electronic tvs, dvds, microwave ovens.

Why did Sony use this in the 600D?

What is used in other MD models normally?

The headphone amp is the Toshiba TA2131. As far as I am aware, it was used in every Sony minidisc player and recorder starting with the R70 first introduced in 2000, through to the first Hi-MD models. Can't be absolutely sure as my service manuals are on another computer, but I am confident this is right.

Jim

[netmduser]

Thanks Jim for the Toshiba TA2131 info I was able to hunt down this http://radiodetail.narod.ru/m_i/m_i_ta/ta2131.htm Now I understand better this is an analog vs. digital scenario for MDs upto the first HI-MD models. Strange in the initial thread someone said it can sound like the RH1 with some eq.

Apparantly this IC has the following features

• 
  
  
• 8mw
  
• beep pins (***beeep)
  
• bass boost function
  

[netmduser]

Why is this unit so thick? Thicker than any of the thickest netmd models.

Is it air cooled?

I forgive the designers of this unit as it sounds very good.

Anyone have the Buffalo version of this unit http://buffalo.jp/products/catalog/item/m/md-husb/index.html ?

[jim.hoggarth]

Why is this unit so thick? Thicker than any of the thickest netmd models.

Is it air cooled?

I forgive the designers of this unit as it sounds very good.

Anyone have the Buffalo version of this unit http://buffalo.jp/pr...husb/index.html ?

Interesting comment. I also get the impression the NH600 is a tad chunkier than, say, the MZ-N510. If I find time today I will do a comparison, and get out my faithful micrometer. It is well known, at least it is to me, that the plastic based NetMD models (including the N710/NF810, for which these are notorious) often crack about the screw holes. Perhaps Sony learned a lesson and made the NH600/700/800/900 etc bulletproof?

Jim

[jim.hoggarth]

Thanks Jim for the Toshiba TA2131 info I was able to hunt down this http://radiodetail.n...i_ta/ta2131.htm Now I understand better this is an analog vs. digital scenario for MDs upto the first HI-MD models. Strange in the initial thread someone said it can sound like the RH1 with some eq.

Apparantly this IC has the following features

• 8mw
• beep pins (***beeep)
• bass boost function

Thanks for that technical info, it will come in useful. Using the N510 service manual as a reference, I see that the bass boost feature of this amplifier is disabled (at least in this model, so I assume all). The standard bass boost employed by Sony is obviously implemented as part of the ATRAC decoding routine.

Incidentally, this is the chip which causes the earphone signal cutting out problem on some models, primarily the R700 and G750. The chip mounting method allows cracked solder joints to develop, especially as the audio amplifier IC is mounted close to the remote control / earphone socket (naturally) which is subjected to minute flexing as the plug connection is 'wobbled' through day-to-day use. Early attempts by Sony to fix this problem included a layer of glue (very hard, almost like a 'cascamite' style wood glue) over the pins of the amplifier IC. This of course makes it impossible to desolder and resolder, so affected boards are as good as useless and must be discarded. Another fix was to jam a block of hard rubber up against the chip, between the board and bottom casing. This didn't cure the problem totally either. Later models suffered less as the remote port was often better secured and the audio IC moved to a different location. It is possible later board were stiffer, also.

Jim

[sfbp]

Interesting comment. I also get the impression the NH600 is a tad chunkier than, say, the MZ-N510. If I find time today I will do a comparison, and get out my faithful micrometer. It is well known, at least it is to me, that the plastic based NetMD models (including the N710/NF810, for which these are notorious) often crack about the screw holes. Perhaps Sony learned a lesson and made the NH600/700/800/900 etc bulletproof?

Jim

I think that's relatively easy to answer.

The NH600 (700 is the same) was based on the NH900 main board and mechanism (check the service manuals). They decided to replace the gumstick battery by an AA. Ipso facto, the unit was almost bound to be thicker by about that much (the difference between the battery thicknesses).

[jim.hoggarth]

The NH600 (700 is the same) was based on the NH900 main board and mechanism (check the service manuals). They decided to replace the gumstick battery by an AA. Ipso facto, the unit was almost bound to be thicker by about that much (the difference between the battery thicknesses).

I think netmduser was already comparing AA-based with AA-based, such as N510 with NH600.

Gotta get a new battery for my micrometer now

Jim

[UK-MD]

Why do they spoil some of these lovely little players by jamming a AA batery in there and making that horrid lump in the back.

[freddyjollo]

well otherwise u get some kind of battery lump like on the Sharp MD-MT88

http://www.minidisc.org/part_Sharp_MD-MT88+MT99.html

The only thing I dislike about these is the tiny and recessed display.

[UK-MD]

Edited June 19, 2013 by UK-MD

[UK-MD]

well otherwise u get some kind of battery lump like on the Sharp MD-MT88

http://www.minidisc.org/part_Sharp_MD-MT88+MT99.html

The only thing I dislike about these is the tiny and recessed display.

So why not use a gumstick battery then ?

How much would a MZ-NH600D be worth today ?

[freddyjollo]

So why not use a gumstick battery then ?

How much would a MZ-NH600D be worth today ?

not a lot. I bought one from Ebay in Uk for £30 I think - that was atleast 3 years ago. ANd bought 2 new ones from Argos cleanout same time for £44 each I think it was. I wont ever buy any portable device that dont use a standard battery like AA. I dont mind the lump either at back or at end. I rather like the thick metal bodied Sharp MT88/99 I have a few - they feel really well made and made to last. May be i get buried with one for something to listen to and give the archaeologists something to puzzle over lol

[McCol]

Picke up a NH600 from ebay last week for £60. No AC power cable but it is in as new condition, also came with a pack of 3 sealed 1gb minidiscs. I've left these sealed as I may sell them on.

The sound compared to the RH1 is a bit warmer, not quite as detailed but still excellent sound.

[freddyjollo]

hmm £60 seems a lot. Maybe I sell the 2 I have which are unused but for testing

[McCol]

I thought it was a reasonable price, it did include 3 sealed 1gb discs which seem to go for over £30 on ebay.

[freddyjollo]

ah yes didnt see that. the 1 GB disks. I have 2 un used 3-packs of them. Any one offer me £20 each disk ? lol ( when I bought them cost me i think £30 the lot )