Yamaha CDX-480 CD player

Megalampized in Dec 2007

Yamaha is a company with excellent marketing. One of the best. While being just a simple Japanese manufacturer of mediocre grey boxes, they have a reputation which most competitor's can only be jealous about. While I find NOTHING AT ALL that sets yamaha to a higher category than the average "others" like Sanyo, JVC or Samsung; but YAMAHA! - OOooo , this just HAS TO BE GOOD. It is sortof like Heineken beer, Alfa-Romeo cars Smirnoff vodka, Levis jeans or French Wines - the consumers at large seem to be massively hypnotized and they genuinely believe these products are great if not the greatest. I think it has to do with CONSISTENCY of marketing message.

Enough politics, I will make too many enemies here. Anyway, back to Yamaha, someone challenged me that his Yamaha is a NATURAL SOUND product and that It will probably impress the living daylights out of me. I gladly accepted the challenge and took the CDX-480 for a spin.

On the workbench upon inspection I wanted to throw the towel and stop this experiment. The guts of Yamaha are so ridiculous that I can't be bothered... well..    ooops .... lets remove the prejudice and look again.

What is funny, there is NOTHING "Yamahish" about this player inside. The mechanism and control part is a cheapest Sony KSS210 with ancillaries. Nothing sophisticated, but an OKAY workhorse. Or work mule.
The PCB is typical Japanese - cheap looking, not impressive, and pure Technics. Yes. This is a MASH based player just like the hundred others out there, like my own babe CAL. Remember the cal? It was a great sounding but fake high end player.

What a coincident: Technics versus Miss Natural Sound - just two different marketing messages, but inside - THE SAME THING.

If I didn't know any better I would probably ridicule the player and close the case, but actually I LOVE TECHNICS DAC CHIPS. I like the Matsushita National MN series of MASH. They sound very clean, open and naturally warm.


The thing that got my attention is that this player has a very simple analogue stage. I still havent recovered from the op-amp bonanza inside the Shanling 300 and Yamaha has .... only ONE OP-AMP in total (double one - that is for stereo). Yes, after MASH comes one opamp, a muting transistor and the output RCA jacks.
This is VERY ELEGANT approach and I understood what they mean: natural sound is a simple way of saying ONLY ONE OPAMP INSIDE.
So far so good: lets lampize it and see if it makes any sense.

I opted for a megalampizator because MASH signal is strong enough (remember, megalampizator is a simple single ended class A triode in anode follower mode and its voltage amplification is circa 2x. Not 20x like other tubes. That's why megalampizator is NOT suitable for current output DACs like TDA1541A.

This is the double triode being the entire output stage of this player.
I took signal from MASH legs and fed it via a cap to the tube grid. Since this is a double triode, I just needed one tube, one heater and double anode supply. One socket and one drilling. Very convenient.

The looks and ergonomics are okay, very distinctively Yamaha, but the amber display uses font 12 or so hence I can't see it from 2 meters.

The new transformer (230 : 110 + 6,3 VAC 20 VA) fits near the original one.. Between the trafo and the drawer are the anode caps.
Unfortunately, since the current to the anode in this tube is circa 10 x bigger than in 6H1P, I also needed 10 x the capacitance in the CRC bridge. I glued together half my drawer of the leftover odd size caps to arrive at 3 x 220uF.

This is a good look at the output stage. Like in almost all Japanese players, the DAC is underside. So it is not visible. Lets agree it is under the place on the middle of the left edge of the photo. From that point you can see a nice symmetrical STEREO row of components, from extreme left all the way to the RCA's on the extreme right.
Worth noticing are especially large hi-frequency killer caps - the C105 and C106 near the RCA's. These make your music dead (and without the noises too). Generally if I see these caps, and I see them in 95 % of players, I call the engineer an asshole and a bastard too.

This mechanism is simple, fast, reliable and easy (cheap) to replace. Nothing to write home about.

The hole for octal socket takes a 27 mm crown bit.

This tube is a very macho thing. Mr. Freud would have something to say about it.

Output caps of new stage

The end result is very pleasing to my eye: the platinum/titanium grey colour of Yamaha is almost identical to the tube silverish grey.

Could there be something more simple than this ???
Actually, the funny thing about the MASH setup is that we do not need to disconnect the old circuit. We can leave it for comparison.

The heaters are AC and there is no hum. DC would become too demanding on my transformer (we need 3 A of heater current !!!) The trick that Ewgennyi taught me is to put a pair of matched 100 Ohm resistors between the heater pins and the earth. Sort of the poor man's humming pot.

You can notice a very low anode voltage of just 40 V DC but apparently this is just okay.

As you probably already guessed from my too long intro, I loved this player. It plays a biiig, effortless and spacious sound. YES, it sounds natural, it does not attract attention to ANYTHING NASTY. I could not criticize this sound even had someone twisted my arm. The marriage of the big 6N13C tube and this player is excellent synergy. I could just listen and listen. Could not find a fault compared to my other super duper gear. The bass is especially good. So deep and powerful, it shakes the house proper.

After a month I tried to install the 6SN7GT tube (6h8, 6N8) and just changed the resistors - anode to 20K, and cathode to 500 Ohms. It plays to my ears even better - there is more micro detail, more air, and more kick. This set-up remained permanent.