[drp]

Today, I started modifications to my Sony D-25 as discussed in a few threads from the middle of last year. Given the age and length of the old threads, it seemed more appropriate to create a new thread. The thread that speaks to the op-amp, PS cap, and DAC modification can found here

Changing out the op-amp was the most nerve-racking exercise this weekend warrior and component burner has ever attempted. Imagine soldering the feet of a slightly enlarged dog tick, without burning the body, and you'll get the picture. Somehow, I pulled it off without burning a hole through anything or grilling the op-amp.

For the caps modification, I left the existing 150uf cap in place and paralleled one Pany .1uf and two 470uf Black Gates in the battery compartment. I still feel like there's a better PS cap arrangement, but I'm a noob so it'll take a while to find the best combination. Ideas welcome……. I plan to eventually place the bypass cap where the 150uf is now (on the jack board) and make room in the battery tray for two 220uf black gates to replace headphone out decoupling caps.

I'm waiting for the DAC, scheduled to arrive this Monday, to create the dual dac, a.k.a. Turbo mod. Wicked nervous about more miniature soldering…. Might seek professional help.

It's hard to gauge the true degree of sonic improvements because of many changes in short period. In addition to the new parts in the D25, I'm burning in a pair of HD650s (at ~130 hours, stock cable), and a fairly new XP-7. I know Ray burns these in for 100 hours, but I want to put a hundred hours or so into the battery circuitry as well before really judging. Also using my homegrown Kimber mini-to-RCA.

But what I'm hearing after the mods so far is a cleaner, more articulate, wider, and fuller sound, throughout the spectrum. I was expecting a bit tighter bass, but every CD I've spun has surprised me. I'm hearing better air and more/complete decay from cymbals all the way through low octave piano notes. It’s for lack of better terms, closer to a decent home CDP. More to do, listen to, and burn in before I attempt additional and as incomprehensible comments….. That and the ZU cable for my 650s…. Stoked.

A special thanks to T; could not have done it without your encouragement and help, dude. Cheers!

P.S. I just spun up Yes Fragile, finding it difficult to type because I'm hearing stuff I've only heard on home reference systems (not mine; can't afford it)…. This is almost scary …. Maybe I won't touch a thing… Nah!

 

[mekanoplastik]

cool....finally another furture member of team turbo!!! .....

please post your impressions about the dual dac mods,..... you will be surprised how much of a difference it makes....

the installation of the dac is not too difucult, dont be intimidated...i did it and that is a prove it can be done by someone with almost no experience...so you will be fine


m.

 

[drp]

Hey Mekano,

You and PuppySlugg collaborated on a very nice mod, thanks for posting the directions and tips.

I went shopping today and found a Bluetack-like substance for the oscillator. I also have some self-adhesive sorbathane tape that I use for tacking down my RC Heli gyros. This mod is just to dampen the crystal oscillator, right? I'm thinking the sorbathane tape would do an even better job…. Comments?

No luck on finding the shielding tape, but have to admit that I just started looking. In reading the original stacked-dac thread in diyAudio.com (thanks for posting the link), the author stated a difference when the dac was shielded. Did you find much of a difference with the dac shielded vs. not?

Found some smaller value caps to move the bypass cap onto the jack board; make room for those hp caps in the battery tray. Should be an interesting mod for when it's just me, the Turbo, and my E5s.

I'll run this beastly setup on batteries at first (building an 8-cell, 1100mAH pack at the moment). This will give me an all DC powered luggable that should sound pretty darned decent. I'll get around to building a PS in the near future though (I get by with a little help from my friends).

Thanks again, and thanks for the encouraging words.

 

[Duncan]

Mekano...

I'm still interested in reviewing a standard vs modded D25S...

Just throw me an email sometime and we'll sort things out...

...Although, I think you have my old email address... my updated one is on the email link in my posts

 

[aixer]

I am just happy with changing the 100uF to Jackcon 1000uF@6.3,
I had 1000uF@10V, but did not hear the difference so I stuck
with 6.3v since the volts across the cap is only 2.63v.

I don't know how better it can get, but all I am saying is
upgrading caps is good enough for me.

I have a AD823 I might put in, I don't know if that would be better or not.

kong

PS I got those caps from my brocken Abit MB LOL, and hopefully
I run into someone with the complete mod in the future to chane my mind.

 

[was ist los?]

Lol, i never got to actually stacking the dacs. So sad. I highly recommend people put a long strip of electrical tape on the under side of the clear plastic on the lid. It helps the D-25 read the cd easier.

 

[drp]

I removed the 150uF PS cap and ran hook-up wire to the battery tray; decided to leave the board unpopulated so I could more easily roll parts (including bypass caps). I replaced the 440x2 and bypass with two 200uF Black Gates, one .1, and one .01 bypass caps. This made room for replacing the headphone out caps. Removed the two 100 uFs, ran more wire, and hooked up 220 uF Black Gates.

Btw - The only cap I did not mess with was the 100 uF cap on the jack board, as I understand that this is part of the battery recharging circuit, and is no longer in play.

New changes!! I performed (and survived) the DAC stack. This was scarier than the op-amp mod, simply based on part cost. Bending SMD leads was also interesting. I'm thankful to Jeff for the D25 schematic (cheers, dude); made a huge difference having this document on hand.

How does everything sound? Is a word: Supreme! I'm spinning Steely Dan's Two Against Nature and everything sounds more in focus and extremely natural. 'Jack of Speed' has never sounded so three dimensional, or fun. I'm still burning in new parts so expect that things will only improve. I'm also burning in that new ZU Mobius (just got it) so I have many things to test and listen to.

So far, I'm completely happy with this mod and would do it again (or hire someone….)…..

Headphone out after the dac and decoupling caps mod: a lil' anecdote - I had my HD650 and new Mobius connected to the HP out to do a bit of burn-in while on errands. I picked up the phones a little later and heard some great stuff. I then reached for the amp's volume knob to reduce the volume. Not that it compares with Emme, but it took a second to register that I was listening to the HP out. With my E5s, the HP out cooks with major fire.

Hey Was ist Los - Thanks for writing. I read about your cap mod several times. Your posts and questions to the Turbo fathers helped me understand what was being done and helped me get through the mod. Tape the window shut, huh? Did you do the green tape thingy? Been wondering about doing that one.

Aixer - Have you compared the specs of the 823 to the recommended op-amp? Seems all that did this particular mod liked what they heard. But, if you already like what you are hearing, that's good enough. Doesn't happen very often in this forum… 8~)

 

[was ist los?]

drp, no not taping it shut!! I mean taping the underside of the window. Just cover it from the inside so light doesn't get into the player through the window. I guess it's the green tape mod, but i just used electrical tape. Works wonders on hard to read cds.

 

[aixer]

can one of you guys who finish all 3 steps,
take apart your unit and shows us some ****.


So that everybody who don't have a D-25
can drew. LOL


well actually I just want to see the power
supply mod close up, if Looks easy I might drop a AD8620 in mine.

thxs

 

[drp]

Aixer - ***** it is!! I have a roll of shield tape on the way so will be back inside the player in 3-4 days. I'll take pics of the various mods. There's already one of the op-amp mod (I think you meant to type op-amp mod, right?), somewhere; will dig it up. I'll also snap pics of the PS though to give a better sense of the layout.

Was ist - LOL, I did mean tape from the 'inside', not shut . . bad choice of words. Good tip; will try. I interpreted the actual 'green tape' mod as taping the entire inner lid (at least the bright circular area) in order to reduce laser light scatter. Still searching for the appropriate material and will do the mod, just to do the mod…..

Also looking for the perfect little rubber baby buggy bumpers for the bottom of the player. Something like what Ray uses on the bottom of the XP-7 would be perfect.

 

[drp]

A few more tweaks and a link to pics. The pics (if this works) can be found at http://photos.yahoo.com/davidp01503

Note: the op-amp pic is one that I found somewhere on this site. My apologies to the author for not remembering who the heck you are. The other two are shots of the caps mod and the DAC mod. I left everything spread wide open for the best in electro-porn…..

Caps pic - Since my last post, I ended up removing that 100uF PS cap and replacing it with a new 100uF cap that I had handy. In the picture, it's at the far left. To the right of this cap is the .1uF bypass and two 220 uF PS caps, all connected in parallel. Further to the right are the two headphone out caps (originals removed). You can also see the stacked DAC in the right center of this shot.

DAC pic - The DAC pic shows the stacked DAC, shield tape, and ground lead (brighter white wire).

What a fun project, and the Turbo continues to rock. I have a D555 on the way so will be interested in seeing how the Turbo stacks up.

Dave

 

[eric343]

What camera did you use?

Excellent job on the mods! I don't think I could have done a better job without buying some solder paste and bringing my $200 SMD hot air station into the works.

 

[aixer]

I think that was the push I needed to continue my mod efforts.

can someone please post a schematic, of
the PS mod I still need some mor info on that.





thxs

 

[drp]

I used a Canon A70. It's 3.2 MP with a few nice features. I believe our Scottder has the big brother. For these shots, I turned off flash, turned on macro, adjusted an incandescent (cough) light, and hand-held the camera (pod would have helped I think). Shot in large format and then reduced by 80%. Pretty forgiving camera, all told.

Thank you, Eric! Personally, I would have preferred to have you, your skills, and your SMD station on the mission…… 8~). I was/am tempted by a unit that is/was for sale, recently, with the possibility of mods as mentioned.

I've been thinking there might be a bit more that needs be done to make this mod really solid. I posted in the DIY Discman Repair thread regarding an existing issue and received a response regarding the possibility of additional caps to handle the voltage change. Suggestions would be great.

Aix - I took a few screencaps of the schematic right around the DAC…. Edit: Added a schematic pic for the PS area, per your request. Good luck!
D

 

[aixer]

I have a question on capacitors,
getting hard to pick.

example: what is the difference between
ones with arrows pointing down on the "-"
negative, some capacitors have that and some just have the "-" sign with no arrows, and some say PET.


Yes I know I am newbie at this LOL.


just to lets you guys know why, I have capacitors lying around, all my brocken mother board and friends fried MB
and power supplys, I took
all the caps from them before getting rid of the board.

thxs


kong