Denon DCD-1290 and DCD-2060 CD Player mod thread

[Bratwurst7s]

28 August 2016 update:

When I got to looking at the schematic of my DCD-2700 I saw that that on the final output caps they had done things a little differently than the 1290. Instead of identical pairs of series/parallel caps they used a pair of 470µF in series and a series pair of 10µF in parallel. I figured that they did that to get better highs and still retain good bottom end so decided to try it on the newest 1290 that I just bought.

10µF MKS2 film caps are pretty expensive so I used a pair of 6.8µF/50v MKS2 and a pair of Nichicon KZ Muse 470µF/50v. Then I arranged for my son and his friend to do a blind test. I only told them that I had done something different and to please A-B the new player with their player. I didn't say anything about what I was hoping to achieve with the change. Both of them reported that their wasn't a lot of difference but that they thought that the bass was a little fuller and deeper with the new player.

So now I've brought all 4 players up to the same standard, the above output caps, KYB 2700µF filter caps, C507 (PSU 47µF/50v) that I had used a FG 47µF/80v replaced with a FC 47µF/100v, 100k ohm resistors on the output-to-ground positions, and LME49720HA/NOPB op-amps with heat sinks in the fixed outputs, Imho the players sound pretty damned good.

It took me a bit longer than planned but I also finally made a parts list/BOM and attached it to the first post in this thread. It's a zipped ".ods" file that can be opened with LibreOffice.

My son's friend let his father use his player to try out and he liked it so much that he wanted one. So since I have now migrated to my DCD-2700 in my main system I sold him my original 1290 at cost with no profit.

Cheers,
James

 

[Bratwurst7s]

OK. So HypnoToad made the suggestion to add 0.1µF film caps across the + & - supply leads of the op-amps to stop oscillation.

If they run hot it could be due to oscillations, try using a 0.1uf film or ceramic cap across pins 4 & 8 (power pins) of the op amp socket and see if it stays cool if it does it was oscillating.

http://audiokarma.org/forums/index.php?threads/op-amp-sound-improvements-challenge.712561/

I seemed like an inexpensive thing to try that might be worthwhile. Today I finally found the time to try it on the player that I was using before upgrading to the DCD-2700. I used Wima MKS2 caps. And I sure thought that I took some pics of the installed caps before I buttoned up the case, but apparently I got stupid and forgot. But I did get some pics that might be interesting.

I've been thinking about how to actually factually prove of there has been an improvement. I don't have an oscilloscope yet so that's out. But I remembered that we have an infra-red camera at work and today I signed it out for the weekend.



To do a before measurement I let the player warm up for an hour and then played Kenny Wayne Shepherd's Goin' Home.

Cheers,
James

 

[Bratwurst7s]

After the warm up I took pics of the 4 op-amps, first the 2 TO-99 ones with the heat sinks attached (25.9°C and 25.1°C) and then the 2 chips on the variable outputs (35.0°C & 36.6°C).



James

 

[Bratwurst7s]

After soldering in the caps I did the same warm up and measured again. The 2 chips on the variable outputs (BB OPA2134) had dropped to 32.1° and 33.9. The cans measured 24.3° and 24.2°. So it looks like the caps helped some at least concerning temps. That's the objective measurement.



For the subjective measurement, I listened to a cd. And the player is sounding killer. My first impression is that bass and mid-bass are improved. For €0.13 each and 15 minutes of work adding the caps is imho a nice bit of tuning.

Cheers,
James

 

[Bratwurst7s]

That FLIR camera is an interesting toy. I was surprised to see that the DAC is running hotter than the op-amps, 40.5°C. And those 2 voltage regulator transistors what were running uncooled till I turned them down onto the chassis? 48.9°. This is making me consider mounting them to a real heat sink rather than use the chassis. I wonder what they were running at with no cooling at all. And the question comes to mind, would placing a heat sink on the DAC's have any positive effect?



Cheers,
James

 

[Binkman]

Greetings; cool project! Pardon pun.
I well for box heat you do have 4 heat sources although not additive all of them together plus the transformer and anything else is total box heat plus the fact the dissipation occurs. I wouldn't worry about it. Just don't stick it in one of those glass vertical coffins and or stack it. Plenty of room for a cpu fan if you think it needs it, just to blow the air around.

bink

 

[NAD80]

The FLIR works great, use one at work to measure heater blankets. Great set of mods with the caps, op-amps, power supply devices. The cd players should sound almost perfect for as long as the laser holds out. Gotta check my Phillips CD-60 and see what I can do there. As for the DAC running hotter than the op-amps there is a lot more in the DACs that's going on.

 

[Bratwurst7s]

While working on yet another of these cdp's recently I realized that I failed to provide photos of the 0.1µF caps that were added to the op-amps. And since adding the caps worked ok in the analog section I decided to add them to the stock op-amps in the digital section. So here are some pics...



Cheers,
James

 

[Bratwurst7s]

The very last thing that I did to my DCD2700 (which I still haven't started a thread for) was change the PSU filter caps because for a long time I couldn't decide on what I wanted to use. That turned out to be a good thing because it allowed me to hear what changes might happen from just this single step. I had already re-capped the rest of the player and swapped op-amps (with added 0.1µF caps). In the end I choose some 4700µF/50v Elna LAO Tonerex caps that I found at Digi-Key.
http://www.digikey.com/products/en?mpart=LAO-50V472MS37PX#B&vendor=604

What happened after changing the caps surprised me. Really surprised me. There was a very nice improvement in bass & mids. A real no-BS improvement. Well worth the €8.22 cost for the 2 caps. I've been enjoying that CDP so much that I bought one for my son for Christmas and did all of the mods to it. So his DCD-1290 came back to me and when bringing it up to the latest set of improvements I swapped in a pair of the Elna's.

It was a tight fit but they did fit, the only thing that I had to do was open up the pcb holes to 1.6mm (1/16") to fit the snap-in leads. It was nice that the pcb actually has 4 holes for each cap, allowing one to shift their positions slightly. Just do a pre-fit to check which pair of holes to drill.



What's next? I've a lot of other irons in the fire at the moment but am starting to look into how to improve the voltage regulator transistors, and still want to build a Flea low-jitter clock kit and psu.

Oh, and the parts list on the 1st post has been updated.

Cheers,
James

 

[Bratwurst7s]

One thing that I haven't discussed, remotes. The original remote for the 1290 is the RC-235. It has 26 keys, some of which are volume and pitch. Oddly enough it doesn't have an open/close key. I've also had on hand an RC-241 and RC-242, which are nearly identical to each other (can't remember the exact differences at the moment) and they both function with the 1290. Both also have 26 keys. They do have an open/close key but don't have some of the keys that the 235 have (pitch is one).

At first I figured that the IR controller could only address 26 functions, but that can't be it because between the 3 remotes all of the key functions work with the DCD-1290. So it would seem that the limit lies with the remote itself. The funny thing is that the remote for the DCD2700 (RC-240) has 36 keys, including all of the different keys on the other 3 remotes. So if you are looking for a remote for a 1290 all of these that I mentioned will work (and probably a lot of others also) but the 240 is the most feature rich that I have experience with, but also the hardest to find.

Cheers,
James

 

[Bratwurst7s]

Today I replaced the diodes in the power supply of one 1290 (P-1) with Vishay Sbyv27-100 soft recovery ultrafast diodes. The unit is the same one that recently got the 4700µF Elna LAO caps. Then I did an A/B comparison with a player (P-2) that identical except that it only has UCC KYB 2700µF caps and original diodes in the psu. The test rig was a freshly re-capped Yamaha AX-750 amp and freshly re-capped Canton Karat 200 speakers. Dire Straits first album was played in both players. The listening room was pretty compromised (small, cluttered) but Wife and Daughters were using the living room.

Obviously this isn't a completely fair test because there 2 components that are different. I'll do this again tomorrow with the filter caps changed in the 2nd player, hooked up to my AX-1090 and Speakerlabs. But I was impatient today and wanted to hear the 2 players back to back. The results were interesting.

This wasn't a blind test, but I can say that it would be hard not to tell the difference between the players. I started with P-2 and it's a very good sounding machine. If I didn't have P-1 to compare it to I could be pretty happy with it. Actually I was pretty happy with it for a time before it got replaced with my DCD-2700. But P-1 stands well above P-2 in sound quality now. Tighter fuller bass and mids. More detail through the whole spectrum but the mids stand out with more clarity and especially more depth. Considering that the caps and diodes together are only about 11€ this is imho worth every penny of the cost.

I'll be doing the change to 2 more players tomorrow and will be able to do some more extensive listening then. But yeah, this is good.



Cheers,
James

 

[Bratwurst7s]

 

[Bratwurst7s]

The verdict is that in my subjective opinion there is a small but significant improvement in overall clarity and depth of sound after swapping the psu diodes. Enough that I did the change to all 3 of the 1290's that I have on hand and the owners of both of the 1290's that I sold will be bringing them back for retrofitting.

Note that the position of the 2x diodes for the digital section is very close to one of the filter caps. If using larger than stock dia filter caps be sure to use the mounting holes their position them away from the diodes. I added a small amount of shrink tubing to the diodes as a precaution.

Cheers,
James

 

[inperson]

I am curious. Could an improvement in sound out of this model be equally achieved by a nice external DAC instead of all this work?

 

[dapbmw]

James,
I have a 1290 as well, I am not good with a soldering gun or reading schematics, would it be possible if I sent you mine for an upgrade?. I live in Canada

 

[Bratwurst7s]

James,
I have a 1290 as well, I am not good with a soldering gun or reading schematics, would it be possible if I sent you mine for an upgrade?. I live in Canada

PM sent.

Cheers,
James

 

[Bratwurst7s]

I'm about ready to work one of these for one of my daughters and decided to re-evaluate the series/parallel coupling caps on the outputs.

I had decided to switch from Nichicon KZ to KL for half the pairs, and then as an afterthought bought some Nichicon 220µF ES Muse BP also.

Today I did a little experiment to help decide which way to go. A pair of 470µF elco in series paralled with a pair of 4.7µF film, or a single 220µF BP elco in parallel with a single 2.2µF film?

I only have 1 KZ 470µF/50v on hand so couldn't make a pair to compare but the one that I have measured 458µF/0.06ohms.

The KLs that I used for the test measured 475.4µF/0.15ohms and 476.4µF/0.13ohms. So the KZ beats them on ESR but I can't measure leakage, which the KL should be better at.
Soldered in series the KLs measured 236µF/0.17ohms.

The 4.7µF/50v Wima MKS2 film caps measured 4.83µF/0.04ohms and 4.84µF/0.04ohms, and soldered in series 2.415µF/0.12ohms.

Soldering the 2 pairs together I got 239µF/0.16 ohms.

A single 220µF/50v ES BP measured 216µF/0.04ohms.
A single 2.2µF/63v MKS2 measured 2.234µF/0.16 ohms.
Soldering the ES and MKS2 together gave 218µF/0.04ohms.

So it would seem that using a pair of single ES BP+MKS2 gives lower overall ESR than the double pairs. What I can't see is leakage.

But if nothing else the overall cost of using the pair of singles is almost €4 cheaper. Heck, that's 1/4 case of beer. Since I have 2 players sitting around here I'm going to set up one with the 2x 470KL+4.7MKS2 and the other with the singles and do a sound check. I'm kinda guessing that I'm not going to hear a difference.



Cheers,
James

 

[Bratwurst7s]

So I worked one of the players today and...darn it sounds good. So good that I've kinda decided not to bother with doing 2 different configs to test.

A few things that I did differently than the last players.

First, while it was interesting to trade the signal path carbon film resistors for film I can't say that I heard any actual difference in SQ. So with this player I only changed the 30k shunt resistors on the final outputs for 100k. R724, 725, 726 and 727. That saves about €10. Those darn CMF resistors are expensive.

Second, instead of using Nichicon KZ 100µF/50v caps for C328, 329, 330 and 331 I used Panasonic FM. As far as I can tell they work just fine and cost €0.21 less, x4 = €0.84 saved.
www.mouser.de/ProductDetail/Panasonic/EEU-FM1H101B?qs=O9nxk9bDVAhpMuLrxh5wFQ%3d%3d

Third, for the 1000µF/25v cap in the digital section of the PSU I used a UCC KYB 2200µF/35v instead of the Panasonic FC 1000µF/35v that I used previously. That cost about €0.48 more.
https://www.mouser.de/ProductDetail...Z1n0r9vR22UhSjrTM10DEWSjivi3Ujtzddqb99MVUog==

Then I used the pairs of Nichicon ES 220µF/50v + Wima 2,2µF/63v instead of the previous pair/series 470µF/4.7µF, saving something around €3.80.
And I added a Wima MKS2 0.22µF/63v in parallel to the ES 220µf and a MKS2 0.1µF/63v in parallel to the 2.2µF on the underside.

All of this saved roughly €14 compared to the last players that I did, for a total cost to do this recap/mod of about €23 and it sounds fantastic. That's pretty cost effective for the sound quality achieved.

I've come to the point now where I've decided that it's just not worth the time and cost to try to go any further with the 1290. It's a very nice CDP and when one can get them cheap enough it's absolutely worth investing less than €25 to improve them but for me it's time to move on. Even though one can still buy Chinese copy lasers the limiting factor will be spindle motors. As they wear the SQ will go and try as I might I haven't been able to find any source for replacement spindle motors.

I think that I'm going to start exploring the DCD 7x0, 15x0 and 20x0 lines of players in the future. (700, 710, 720 etc).



Cheers,
James

 

[Bratwurst7s]

 

[Stephen300]

Just pulled my 1290 out of mothballs and thought I would open it up and do a few mods. I read earlier in the thread that "4 muting transistors" are removed. Am I correct in thinking these are TR714, 716, 718 and 720? What about TR713, 715, 717 and 719? I see in one photo that the first group (odd #'s) of transistors are removed and then later on I see a photo with the 2nd group (even #s) also removed. Should the earlier quote be changed to "8 muting transistors" are removed?

Also, I tried DLing the parts list linked in the opening thread but it keeps coming up as being corrupt. Can anyone clue me in on this list please?

Many thanks!