[ SACD enhancer ]
class A discrete transistor output stage for Sony DVP-NS900V
last update: May 05, 2003

This year it will be 10 years ago that I bought my very first cd player, a Sony CDP-791. I was very late in buying one, not because of audiophile worries about the format but simply because I was in highschool and on allowance budget. From my first self-earnt money I bought that trusty old Sony that never skipped on any disc (can't believe I ever sold it!). Now, 10 years later, a new format is out and I want to jump onto the bandwagon a little sooner this time.

I have known the SACD format since 1999, when it was still in its development stages. I had the pleasure of participating in some listening tests determined to set the parameters for the multichannel format. Back in those days, the goal was a 6.0 format, which was later reset to 5.1 because noone will put 6 front speakers in his living room, not even me. I do remember however that it sounded great, the added channels add an extra dimension to mostly the ambiance of the music.

So when the first players came out I held out for a while until the multichannel players became available. Also, I wanted a player that would play DVDs as well. I wanted a DVD player anyway and would not settle for 2 boxes. Now, whatever I tweak in this player will benefit DVD playback as well. The Sony DVP-9000ES was one of the first that would do this but doesn't play CD-R(W)s. Then the derived DVP-NS900V and DVP-NS700V came out. I hesitated for a bit between those, finally settling for the 900 when tax season turned out favorably (later when I saw the 700 in real life, I was sooo glad I didn't buy this flimsy plastic thing).

When it arrived, I turned it on, found out how it worked (I guess it came with a manual, but that's for losers) and took off the lid. Just part of the packing material anyway.

Mwoah, inside it doesn't look half bad. At the left hand there's a switched-mode PSU that feeds the mainboard and drive section. The R-core tranny only feeds the analog output stages, very nice! No cross-talk from servo's that way. The drive is simply amazing. I remember how the early players took up to 40 seconds to recognize an SACD- this one does it in under 4 seconds. It spins up like a rocket. Keep clear. In the back, there's the video output board (under) with a very nice Analog Devices D/A converter. The image from the DVD is very good, even on VCDs. The video section can be turned off when using the player for audio.

The audio board is located above the video board. You can see the 8 analog stages. From right to left: 2 for stereo, then 2 for front, 2 for rear and 2 for centre/sub. There are 4 JRC opamps, running on regulated supplies (no 78xx/79xx !) with some quality electrolythic caps. Not bad, not fantastic of course. But this is just what I wanted, I bought the player with a tube output stage in mind, so I wasn't spending money on an ES output stage.

Did you have your ration of transistors today? I did... it looks like freaking silicon valley down here. The lower ICs are the MPEG-2 video processors and include a complete filtering and equalizing set to tune your image. The upper stuff is for audio. A DSP turns multibit words into 1bit data and includes filters for virtual surround, bass management and speaker level setup. The DSD processor decompresses and reconstructs the 2 or 6 channel stream from the disc before passing it over to the DAC on the upper right. Knowing Sony, it may well be a current pulse D/A converter. Will measure later.

Functionally, there's nothing wrong with this machine, it's a Sony in that sense, everything is cool and everything is smooth. The mechanics are excellent. The drawer opens and closes gently, the drive is FAST!, even on regular cd's. You can shuffle through a live concert disc, the random access time is less than nothing. Does that matter? No... but it's so cool, gives a sense of utter control.

The sound was not fantastic as I already had suspected. Kinda dull, no highs. SACD wasn't convincing either, the player was even with SACD not as good as my trusty Pioneer with regular CDs. I left it playing more or less constantly for a week and that did a LOT. I am not so used to opamps, and the last time I listened to a brand new machine was years ago. So I was kind of surprised to hear the difference. Now SACD starts to display the characteric differences to CD I remember so well. The space, easiness, bass control and detail are outstanding. However, and this is more of a suprise to me, regular CDs sound excellent through this unit as well! I don't know what the unit does to them, but the spatialness is good, the level of detail is better than any CDplayer I have yet encountered. Only the typical opamp weakness remains, the highs are too artificial, mids are weak, voices too dry, there's no sparkle.

So: time for a tube project. This project will most likely use the monster trannies from the CDenhancerII of the Pioneer player for the front channels. For the rear channels, I'm thinking of a simpler stage using capacitors and a buffer tube. Six transformers is a bit too heavy on my budget and the rear, centre and sub are not even used that much, that is not yet. My system still needs 4 more speakers and amplifiers in the first place.
All this stuff is probably going to take in so much room, that I'll be building it into a separate chassis. I also really don't want to butcher the case of a ONE week old player...


May 05, 2003
The player has now been here about a year and a lot has changed. The tube stage worked ok. Nothing new there, however I decided it was time for a new challenge. I would try and get as close to a tube stage as possible with... transistors.

I did however not see coming that it would turn out this good. In terms of space involved, power dissipated this is already a winner, but when you add its sound it's unbeatable.

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