• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Denon DCD-2700 CD Player Mod Thread

First during listening throught the headphones, I was very happy, the sound was very stable/peacefull/controled but throught speakers I experienced a return to the beginning, the sound lost highs, vocals became withdrawn but bass became very exposed,
colorful and detailed in turn dynamics became too slow and uniform. I removed cap from secondary windings but in the future I will experiment with other capacitances/caps to find best rythm/balance.
 
And the changes...I needed some time to learn the scene anew, because it expanded and deepered significantly. The sound is cleaner / clearer I closed to right balance between lows and highs but feel that adding second transformer and new caps in connection that gives low impedance and more capacitance in analog section is needed to this configuration, the sound is changing/new elements need time to fully express so I will wait with final opinion some time
 
Last edited:
Hi Slawek,

Nice work! Very interesting. Can you tell me what the yellow caps in the analog section are? I had thought of putting some film caps on the output but in the end used a combination of small films and big elcos because of size and cost.

Yes, it's always good to take some time to get the feel of each change before making the next one.

Cheers,
James
 
Hi James,

Thanks. I chose the caps intuitively. Now I found that they are film metalized-tantal capacitors 10uf 250V 5% , They are used in crossovers typically. Akyga is polish firm, but I think that the caps are produced in China. Price is about 1 Euro.

Some more feelings about changes in the sound. Yesterday I had dilemma during listening the music, the scene is so big and deep, the sounds are so pure,clear,rich and sturated that the music is close to life music and therefore is very absorbing/engaging. I couldn't listen "just one ear" I had to listen all my awareness, even on small levels of the volume. I coudn't ignore the music and this began to disturb me. Fortunately ;), I discovered very low volume levels in cases I will want to listen only "one ear" And the last feeling, after long session of listening I realized/discovered a small unbalance, the sound generally is a little bit dark/heavy, because bass and mids are now in my opinion OK, I realized that this "haviness" is a small lack of highs, so after power supply upgarade I will be looking for improvements in highs.

Cheers,
Slawek
 
Hi Slawek,

I think that you will start to hear the missing highs and hear tighter mids after you change the op-amps in the analog section to the LME49720 and remove the BA15218 filter op-amps.

I also realized yesterday that we are overlooking a part in the power supply. IC-705 is the bridge rectifier for the + & - 10v and +5v rails in the digital section. It is a 1SWB(A)10 chip. Mouser has the data sheet for the 200v to 800v reverse voltage versions, I believe that we are dealing with the 100v reverse voltage version of that chip.
http://www.mouser.com/catalog/specsheets/J534S1WBA.pdf

Looking at the data sheet I don't think that there is any reason that we can't use 4x SBYV27-100 diodes to replace this bridge rectifier chip. On the weekend I'm going to try it.

Concerning the PSU caps C-707, 708 and 709. Do you think that they are supposed to reduce ripple? The LM317/337 voltage regulator boards that I built have caps in the circuit that are doing this job. I will be posting about my results with them soon.

Cheers,
James
 
Hi James,

Yesterday I didn't notice this "haviness" I noticed something else, I can describe this as squeaking tone which is audible on trumpets, violins and vocals, not always audible, intuitively feel that most of this comes from transformer. It's interesting that when the sounds become pure and clear, become audible all unbalances in timbre and high end fun begins ;) . Mayby this squeaking was the reason why they set DCD 2700 tonally with withdrawn vocals and strong, expanded lows - to hide it. But I feel that I will eliminate it. [Edit: but yes I'm curious about changes connected to op-amps, but I'll do them at the end :) ]

My Intuition says that 4x SBYV27-100 will be perfect for this :) , but now direct me to x201 4.23 Mhz ceramic oscillator and inspire me to just replace it with 4.43 MHz Quarc and I'll do it.
Yes I feel that C-707, 708, 709 are supposed to reduce ripple as C701,702,703,704 , C706
Yesterday I've got transformer, I hope this weekend I will mount it and replace caps.

Cheers
Slawek
 
Last edited:
monkas said:
Now I found that they are film metalized-tantal capacitors 10uf 250V 5%
Click to expand...

The DCD-1290 has the same configuration of output coupling caps as the 2700, 2x series pairs in parallel with each other. Some players had all 470µF/50v, some had all 100µF/50v originally.

I tried many different cap configurations with my 1290. 4x 6.8µF film, 2x 6.8µF film, 4x and 2x 10µF film, a single film cap, etc. In the end I settled on 1 pair of 470µF/50v Nichicon KZ and 1 pair of Wima MKS2 4.7µF/50v. Since the pairs are in series/parallel that gave me the equivalent of 1x 235µF BP in parallel with 1x 2.35µF. I liked the way that sounded the best so that is what I've been using in the DCD-2700.

Cheers,
James
 
So today I replaced the S1WB(A)10 chip with my home-made SBYV-27 bridge, and afterwards replaced the 3 voltage regulators with my LM317/337 boards. I listened to a cd between each step.

DSC04106.jpg DSC04107.jpg DSC04108.jpg DSC04109.jpg DSC04110.jpg

I marked the leg spacing of the chip on a piece of board, drilled some 1mm holes to hold the diodes and built up the bridge on the workbench before installing it. That was much easier than trying to build it directly in the psu pcb. Also, I used a marker to mark the +,-, and sine leg positions on the pcb before removing the old bridge chip.

Cheers,
James
 
Installing the voltage regulator boards meant bending the small sections of pcb that the old ones were mounted to back to horizontal. And because of the size of the new boards I had to stagger the + & - 12 boards to get them to fit. At the moment they are just standing in place but I'll be making some braces or frames to hold them to remove any weight/stress from the solder joints.

Oh. Forgot to mention. I bench tested the new regulators with a bench power supply last week to make sure that I hadn't done something wrong that would melt down my CD player. They checked out fine.

DSC04121.jpg DSC04122.jpg DSC04124.jpg DSC04127.jpg

Cheers,
James
 
DSC04134.jpg DSC04136.jpg DSC04137.jpg DSC04138.jpg

So how the heck does it sound? Freaking awesome! Striking clarity, depth and each instrument and singer is presenting itself as a cleanly separate entity. It's just freaking awesome. This is an entirely different machine than the one that I bought. My thoughts are now moving towards a low jitter clock.

Cheers,
James
 
BTW, another development. Last week I saw another DCD-2700 for sale on ebay and was able to buy it for €82 including shipping. It's not in great shape. Somewhat scratched up, all of the feet are missing, the mains plug and lead is missing from the PSU board and someone has soldered a short length on heavy mains lead directly to the pcb without a strain relief. And it was sold as not always reading cd's correctly. We'll see.

The important thing at the moment is that it gives me a platform to try out more exotic experiments on without risking my main player. And I'm making the first tentative thoughts about perhaps etching a new power supply pcb. There is room for a larger board. One that has the LM317/337 circuits built in and has spacing for larger filter caps and perhaps a torroidal transformer. Just early thoughts at this point. I know how to etch, that's no problem. Getting the photo-tool made would be the expensive part. But it's something worth looking into.

Cheers,
James
 
I have to admit to having gotten tied up in other projects and haven't done anything new with my 2700 except use it.

Every.

Single.

Day.

:):music:
James
 
808_state said:
May have a tray issue with a 2700.
Click to expand...

monkas said:
Hi James and All interested
I have a lot of new expierience in moding DCD 2700 ( also painful) , I will put/post it soon.

Slawek
Click to expand...

??? Any progress?

A small update. While working up a renovation parts list for my new Yamaha CX-1 pre-amp I came across the correct relay replacement for our DCD-2700's. Mouser has them and they are only €2.82 each...
https://www.mouser.de/ProductDetail/Fujitsu/RY-12W-K/?qs=pc5iSNpyspZCkKjXcqIUqw==

Cheers,
James
 
You must log in or register to reply here.
Back
Top Bottom