Sony CDP-337ESD Review (CD Player)

[NTTY]

Yep, quantization errors are not always harmonically related to the input signal, they are mathematical errors due to the limited number of bits to represent the input signal.
Dither has both advantages of 1) reducing quantization errors and 2) masking effect at the expense of increased noise floor (but less audible).

 

[little-endian]

Dither has both advantages of 1) reducing quantization errors and 2) masking effect at the expense of increased noise floor (but less audible).

Well, my argument I was trying to make actually was that

1) it doesn't only reduce quantization errors, but ideally entirely eliminates them and

2) it doesn't "mask" anything but rather "reveals". For instance, dither allows information to be resolved even below the least significant bit with PCM which otherwise would be entirely lost

 

[NTTY]

True, with dither, we can represent a signal way below -96dB (with 16bits data). And with shaped dither (noise), we can go deep down to 20bits.

 

[restorer-john]

I bought a CDP-338ESD new in the early 1990s and used it for many years until the transport got dodgy and tended to skip on Track 1, then play the rest of the disc with no problem. Cleaning the pickup didn't help. Fine tuning the adjustment pots on the servo board didn't help.

Maybe I should pull it out of the shed and check those capacitors!

If it skips on tracks one and two and then settles down, it's most likely the spindle motor. The 338 uses an inexpensive spindle motor and like all that are driven hard in order to get fast spin-up/down access, the commutator and brushes take a lot of wear.

The inner tracks require faster revolutions. Listen to the player immediately after loading discs and pressing play. Do you hear a resonant whine from the player itself as it skips? That will be the upper sleeve bearing on the spindle motor, right under the table. You need to get in there with a fine needle oil applicator and put a drop or two on the shaft.

I'll send my invoice later.

 

[restorer-john]

My favorite part of the review:

 

[restorer-john]

I have a friend who specialises in these old Sony players here in Poland - he says that 95% of those ES models that are being sent over for not reading CDs have lasers in perfect shape (and all pots completely out of whack, "tuned" by techs that have no idea what thay are doing).

That's perfectly true and has been the case for several decades now.

With most "techs" having no test CDs, very little skill or actual understanding of these players and no LPMs (laser power meters), they basically tweak pots, make a mess and say "the laser is dead- no parts available" and these magnificent machines go into landfill.

 

[Newman]

If it skips on tracks one and two and then settles down, it's most likely the spindle motor. The 338 uses an inexpensive spindle motor and like all that are driven hard in order to get fast spin-up/down access, the commutator and brushes take a lot of wear.

The inner tracks require faster revolutions. Listen to the player immediately after loading discs and pressing play. Do you hear a resonant whine from the player itself as it skips? That will be the upper sleeve bearing on the spindle motor, right under the table. You need to get in there with a fine needle oil applicator and put a drop or two on the shaft.

I'll send my invoice later.

If that works, the cheque will indeed be in the mail! Thanks!

That's perfectly true and has been the case for several decades now.

With most "techs" having no test CDs, very little skill or actual understanding of these players and no LPMs (laser power meters), they basically tweak pots, make a mess and say "the laser is dead- no parts available" and these magnificent machines go into landfill.

I have probably done exactly that to the pots of my 338, trying to fix it. Is there a general tip for how to get them right?

cheers

 

[restorer-john]

I have probably done exactly that to the pots of my 338, trying to fix it. Is there a general tip for how to get them right?

Do the spindle motor lubrication first. Either remove the mech, stand it on it's side and get in there with the drop of machine oil or eject the tray, turn off the power, move (carefully) the laser block out of the way and use a torch to see the the bearing/shaft. It's difficult as the gap is only about 1-2mm.

Also, clean the pickup sled guides and re-lubricate with a silicone light weight grease. It's a linear transport, so no gears/racks to worry about. The brass slide bearings will be caked up- clean them with a q-tip and relube.

If you've tweaked the pots too far you could have more problems. That said, the 338 is pretty forgiving as a lot of the control is digital and handled by the LSIs, unlike earlier generations.

You can check the basics here, if you have a scope and freq counter.

If you are ever tempted to tweak pots (as you have nothing to lose), put a fine marker pen line on the pot wiper/body so you can return (close enough) to the position it was prior.

If you tweaked the pot on the laser pickup head itself (I hope you didn't) all bets are off.

The CDP-338esD is a fabulous machine. Get it out of the shed- it deserves better.

 

[NTTY]

My favorite part of the review:

View attachment 418699

Holy whit

 

[WDeranged]

Great review. I love these old players.