Marantz CD 63 LLE

Marantz CD 63 LLE - Lucio Limited Edition -

The Marantz CD63 is currently available in three different versions:
the mkII, the SE (Special Edition) and the KIS (Ken Ishiwata Signature). Prices vary from 500$ for the mkII till 1000$ for the KIS (please note that these are current prices in Italy, they could be very different in other Countries).
The two expen$ive versions (SE and KIS) differ from the standard mkII because they use a stiffer and heavier cabinet, better passive components and a nice toroidal power transformer (KIS only).
The CD 63 mkII is renowed for being one of the better sounding CD players available in the market for its price and it has quickly become an *instant classic*.
We'll make it better :-)

The cabinet

The weak spot of every budget-conscious CD player is the cabinet. Indeed, the first step of any tweaking is to make the cabinet stiffer (as Marantz did, actually).
Given the fact that the upper cover is very weak and prone to sound like a gong I've decided to throw it away literally, replacing it with a similar C-shaped cover made out of foam-rubber (pretty thick: 2 cm - 1 inch).
This way we protect the player from dust and moisture AND get also a better sound (see below for details).
Not only the top cover is pretty resonant, also the rest of the cabinet needs some *tweaking*. Take some blue-tac and put it onto every panel of the cabinet.
You just need 5 or 6 strips of blue-tac (each strip being 10 cm -4 inches- long) and you're done. Choosing the right place WHERE to put these strips is fundamental: do the choice *by ear*, ticking each panel and listening to the resonancies. As a quick rule of thumb you can start from the center of every panel.

The CD transport

The upper part of the CD transport has two rectangular grooves that you should fill with blue-tac, taking care to avoid any excess.
Then take a look at the power transformer: there's an aluminium bar over it that links the lateral panels. This bar needs to be blue-tac_ed strongly because it could be very resonant.

The power supply

The AC cord of the CD 63 mkII is really poor. Buy an IEC socket, make a hole in the rear panel exactly where the stock AC cord comes out, CUT the cord and sold it to the socket, then screw up this to the panel (make sure that the hole isn't wider than the socket...).
Now you are ready to use a special AC cord, I've used a Next Tecnos but, if you want to save some money you can use a home-made AC cable, using a standard 3x1.5 copper shielded mains cable (easy to find and very cheap).

The feet

The feet of the CD 63 mkII seem to be designed with something in mind since the rear ones are different from the front ones. Clearly there should be a *sonic* reason for this otherwise strange choice.
I've tried to replace them with three pin points but the results haven't been as I expected to. Since my CD63 sits over a tempered glass table (Alphason), very stiff and with pin points everywhere, I suspect this combo makes the coupling of the player with the floor (and the room) way too stiff.

How does it sound?

The more audible difference is in the bass range, now deeper and more powerful.
Now my CD63 has a bass range similar (even if NOT equal...) to my Linn turntable: especially in the lower bass range the CD63 LLE sounds with plenty of power and the bassiest notes now tend to expand into the listening room while they were somewhat *shadowed* by the upper bass before.
These improvements were due especially to the tweaks on the cabinet and the transport while the shielded power cable brings new life to the upper-mid and high frequencies which become cleaner and more dinamically involving.
The 3D soundstage is a little bit wider, too.

The cons of the CD63 LLE

Of course these tweaks make your warranty VOID and in the case your CD player would ever need some service you should try to explain to the official Marantz technician the WHYs and the HOWs of such strange modifications.
Plus, the foam upper cover may look pretty ugly (low WAF...) and the internal circuits are now more exposed to external agents like Coke :-) during a party (I'm pretty sure that a CD63 LLE would never be treated this way).
Then, please, do not think that a CD63 LLE sounds like a Wadia. After all it still remains a budget-conscious CD player improved in some areas (in the bass range, especially) and only slightly more refined.

How much does it cost?

That highly depends on the Country you live in. Here in Italy all these tweaks would cost no more than 15 US$, shielded power cable included.
And couple of hours of work, since the trickiest part is cutting the "right" hole into the rear panel for the IEC socket.
Try these tweaks and I'll be mostly glad to hear your comments.

Reclocking!

Ready for more radical tweaks (reclocking!)? Read on! (the following courtesy by Martin Clarke of http://www.acoustica.org.uk

Having spent far too long playing with my CD transport I finally did something useful - so here it is for all you inveterate tweakers. For my money this is the best 1/2 an hour you can spend meddling with the insides of the Marantz CD63.

Recipe:

1no. cd63/63SE, maybe CD67 also...
1no. NPC SM5872B DAC datasheet, available from ftp://ftp.npc.co.jp//pub/pdf_e/nc9242ae.pdf
1no. 0.1uF or greater Stacked foil polystyrene cap (must be less than 1/8" thick)
1/2" plain copper wire
Sharp knife, steady hand, soldering iron
Willingness to pull the logic board and solder to surface mount devices.

The clock in the '63 is a simple Pierce oscillator implemented directly on the DAC chip using a purpose-built logic gate. The relevant components are the DAC, CD02, CD03 and the 16.9MHz crystal, XD01.
Whilst obviously a product of mass-production in its execution, having the clock built into the DAC is potentially ideal; but the clock in the 63 out of the box is pretty jittery, and those who've tried reclocking devices report tremendous gains, as you might expect after spending all that money.....

After *much* hacking about with my old 63SE I think I've found a good reason why. Go read the datasheet at this point and come back here afterward.

The crystal is connected across one end of the DAC chip, between pins 1 and 28. The 30pf (I think) caps CD02 & CD03 tie both sides of the crystal to the ground plane via a PCB trace, basically forming a series resonant circuit when excited by the logic gate (between pins 1 and 28 internally) through RD02 *which you should not modify*.
The logic gate on chip even has separate digital supply and ground pins for to decouple power supply noise, pin 2 is digital ground and pin 27 the logic gate +5v supply.
Pin 27 is fed through RD01 and decoupled by CD04 (electrolytic) and CD05 (tiny axial ceramic). So far, potentially outstanding.
The problem is that, as laid out on the board, the decoupling is ineffective - too much trace inductance renders CD05 & 05 ineffective - *and* the logic gate ground interferes with the oscillator!!! Pin 2 (logic ground) is connected to the ground plane from the _far_ side of CD02 & CD03, so every time the logic gate changes state, the voltage change across the trace inductance will directly modulate the series resonant circuit, because CD02 and CD03 are no longer at quite the same potential. ... no wonder there's so much chaos in there.....

The cure is simple. We place a very low inductance capacitor - stacked foil poly types work for me, ceramics are another good option - directly across pins 2 and 27, as tight to the chip as possible. You need the lead lengths under 2mm for the cap to remain effective into the RF range.
The DAC is a surface mount device, so the best way to achieve this is to pre-bend the leads until the cap just fits across the DAC pins and clip them until the cap. sits tight against the top of the chip - when the board is reinstalled, you'll only have about 1/8" clearance from the case for this cap to fit into!
Now pre-tin the cap leads with solder off board, then holding the cap in place, when you're sure you're in the right place, momentarily touch the cap leads with your soldering iron and the cap will be soldered in place.

Now we get rid of the ground bounce problem. Locate the ground trace from Pin 2 and follow back around to the ground plane under the DAC. Take out the scalpel and carefully cut the trace between pin 2 and CD02 solder pad, as close to CD02 as you dare, and again as close to Pin 2 as you can.
We're isolating the trace -soon to be redundant- so it doesn't form an aerial....peel it off the board if you can!
Having cut the trace out, take your 1/2" piece of wire and solder one end to the ground plane where CD05 connects from above and the other to the lead on your new cap at pin 2 - make sure you don't short pin 1!

If you've followed Bobwire and Thorsten's tweaks here on TNT-Audio, then you've probably swapped RD01 for a small axial inductor and a couple of ferrite beads already, and increased CD04. If you haven't, then do it now.

That's all there is to it - once you've got the board out and can trace the circuit this really is *a lot* easier than it sounds - when inspiration struck it took me just 20minutes to do this tweak (but then it took two years for the inspiration to strike!). To my ears the gains have been terrific, esp. the vastly improved P.R.A.T., but bass freaks will be pleasantly surprised also....it is a change of greater magnitude than Bobwire's internal coax swaps.

Incidentally I think the "ground bounce" issue is why "superclock" upgrades work so well. If an external clock is used, the signal is fed into XTO (pin 28) and CD02, CD03 and XD01 are removed. Which means the internal logic gate is still used on the DAC, but it now has the ground trace to itself and so cannot modulate the oscillator operating conditions.
Those with a clock upgrade still might like to try the additional cap though.....maybe someone with access to an oscilloscope could have a poke around and see what's really happening!