An OEM CD-94 by Micro Seiki

An CD-M2 sold by Hifido Nihonbashi; Photo Credit: Hifido.

When Micro Seiki entered the market in 1987 with the CD-M2, it must have raised some eyebrows. Slightly higher than a Marantz CD-94, you must have been surprised when you found out it weighed a hefty 22 kilograms picking it up! It also came with bold marketing statements like: “previously unobtainable transparency, and an extremely high signal to noise of 140dB” and its design for high quality and professional systems.
At least, that is what the press release of Audax in Australia wanted us to believe. On the Australian market, you could buy it for AU $5500. If you had to buy this cd player today, you would pay $10000/€8500 (inflation-corrected). Second-hand prices; expect to pay up to ¥178,000 without shipping and import taxes on Yahoo Auctions.
Ask any expert on the CD-M2, and they will tell you that it is superior to the Philips CD-960 and the Marantz CD-94. Why would you ask? The anti-vibration measures used in the CD-M2 are the main reason.

An Micro Seiki AP-M1 sold in Moscow; Photo Credit: Avito Russia.

Micro Seiki became famous mainly for the excellently designed turntables. From 1980-1989 Hideaki Nishikawa held the position of manager of the technical department at Micro Seiki. He later became the Sound Business Director at Micro Seiki. Under his guidance, Micro Seiki developed the SX-8000 system turntable. It was in this period that Micro Seiki developed the AP-M1 and AP-M2 turntables. These turntables share a lot of similarities with the CD-M2. The CD-M2, AP-M1, and M2 used Brasilian rosewood to diffuse any vibration and Cosmal ZM-11 in the turntables and the cd player to construct the chassis. This zinc-alloy got known for its high rigidity, high internal vibration damping, and very high signal-to-noise ratio. Mitsubishi Steel and Kobe Steel were the companies that supplied Marantz and Micro Seiki with special alloys and knowledge.
In the case of the Micro Seiki CD-M2, most produced parts came from other companies.

Clockwise; The shielded power transformer; balanced output transformers; bottom panel wich consisted of ferrite, lead and metal plates; PP-16 printed circuit board with zinc-aluminum frame.

To see how the CD-M2 differs from the CD-94, you have to open up the enclosure. In case of the Marantz CD-94, one can take the side panels and top panel off. The CD-M2 is more challenging because you have to remove the bottom panel first before removing the top panel. The top panel is heavy and made of an alloy called Cosmal-Z. Cosmal-Z was a newly developed metal designed for extreme rigidity and vibration damping characteristics compared to conventional aluminum alloys. The most eye-catching differences are the Brasilian rosewood casing and the so-called HAI-60 feet that were useable in two ways! The front flap with the controls is missing on this player, and the power button hides in the Micro Seiki label. Opening up the CD-M2 lets you see the triple-layered bottom plate, the copper shielding of the servo board and the PP-16 board, and the shielded transformer. If you remove the copper shielding, you can access the printed circuit boards and the balanced output board. The CD-M2 also features better gold-plated connectors (the ones on the CD-94/CD960 loosen over time), an earth connector, and a “balanced” output-board, supplied by Tamradio.

Multiple output configurations offer 600 ohm balanced XLR cannon connectors for professional use, single ended 2V RCA gold connectors, a fivefold sandwich structure, qaudruple statis shielded transformer and a balanced line output offerering two cannon to gold plated RCA cables supplied as a standard accessory.

The CD-M2 also shares the same chassis, printed circuit boards, and the famous CDM-1 drive from Philips. Every CD-M2 got the same factory sticker on the CDM-1 and the chassis; the one that the CD-94 is wearing on the back. The sticker lets you know when the player left the Sagamihara plant. This player only came as the MZ01 revision, and later the CD-M100 used the MZ02 version. It looks as if the player used the TDA1541-SAA7220P/A combo only and never got the TDA1541A-SAA7720P/B upgrade1. The complete cd-player likely was manufactured at the Sagamihara plant, but I don’t know that for a fact2.

It seems that many Japanese owners cherish the CD-M2 as a gem and are not going to get rid of it anytime soon…

If you want to experience the full potential of this fine cd player, you must jump some hoops first. First of all, start by upgrading the CDM-1 belts to the blue ones supplied by Dindiki in Germany! Second, on your list should be a full recap, and don’t forget blue Philips axial capacitors! Third, get a good TDA1541A-SAA7220P/B combo to replace the TDA1541-SAA7220P/A. Some advice; stay away from Chinese sellers of these IC’s because they probably sell you reprinted IC’s that will negatively influence the sound of your beloved CD-M2. And consider that the Marantz CD-94 and the Micro Seiki CD-M2 used selected TDA1541’s; replacing them with reprinted Chinese ones (unselected) is ridiculous. For a recap, you can use Nichicon KG(M), Panasonic M, Panasonic FR, Elna Cerafine and the green Nichicon bipolars. An upgrade worth mentioning, and that also measured well, is replacing the TDA1541 decoupling capacitors with Kemet SMR (PPS) combined with a so-called Grundig DEM mod. This modification also works wonders in the Marantz CD-94, CD-94MKII, CD-95 and CD-99.

An upgrade worth mentioning, and that also measured well, is replacing the TDA1541 decoupling capacitors with Kemet SMR (metallized polyphenylene sulfide film capacitors) combined with a so called Grundig DEM modification…

When servicing this kind of old cd player, don’t forget to check for cracked, fractured, or broken solder joints and resolder the circuit boards. Check the wire bridges, resistors, and diodes and clean the circuit boards with isopropyl alcohol. Make sure you can enjoy the CD-M2 for the next fifteen to thirty years!

The experience was rich and I believe most rewarding, for Micro Seiki have created a CD player which is capable of extracting audible nuances and refine-ments from the original material content that I would have not believed possible…

CD players can extract only 80% of the data from the compact disc medium, as one of the engineers from Soulnote (Kato San) pointed out. And considering that this might be common knowledge amongst the engineers that work at Soulnote (and used to work for Marantz), the Micro Seiki CD-M2 might be one of the first CD players that attempted to extract more from a compact disc. This statement is supported by measurements as well. Whereas the Marantz CD-94 managed a signal-to-noise ratio of 96dB, the Micro Seiki CD-M2 managed an unreal 115dB (with emphasis 120dB!). According to numerous Japanese sources, it is possible to hear in un-explored dimensions with the CD-M23. And for the tweakers among us: achieved with a TDA1541, a SAA7220P/A, and four 5534 op-amps (pun intended!). I think that Ishiwata San saw this potential too when he started working on the Marantz CD-7.

[1] Input/feedback needed.

日本語入力またはフィードバックが必要です!

[2] Input/feedback needed.

日本語入力またはフィードバックが必要です!

[3] Experiences are welcome! And will be published!

このプレイヤーとの日本の経験は大歓迎で、公開されます!

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