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Toshiba 3950 power supply mods (with pics)

post #1 of 353
Thread Starter 
Today I got the capacitors I had ordered from Digikey to do the Vinnie Rossi power supply mods for the Toshiba.

Take into account, I'm basically a real newbie as far as DIY electronics is concerned. Had done a bit of soldering about a decado ago, and only today I tried again. First I had to go and purchase a few set of basic tools as listed in the starters kit in one of Head-fi's DIY forum stickies, which included basic soldering iron and stand, solder, desoldering braid, and desoldering pump. Decided to also get an Anti-static service kit from Radio-shack. Couldn't find the clip-on magnifiers recommended by morsel, so at least to have something, just bought a normal large magnifier in Eckerds ($5). Multimeter, cable cutters, and pliers I already had.

Setting up the anti-static mat properly and testing it, then disconnecting the player, opening the case, removing the power supply board, then getting everything soldering-related ready for desoldering the first capacitor, took me more than an hour for sure. At that point, I took this "before" picture.



The desoldering of that very first capacitor (brown, largest one), and then soldering the replacement, was a roller coaster thrill ride for me. Every second I was fearing either burning something or getting the capacitor blown in my face because of excessive heat. Needless to say, I was also wearing protection glasses over my prescription glasses, just in case.

After a couple of hours (yes I was that slow ) it took me to do these replacements of a few capacitors, I took these "after" pics.






Reinstalled the power supply board in the player, reattached the cover of the chasis, and then tried it, with sufficient precautions in case something was going to smoke. I used a line filter switched off, plugged the power cord, stood a few feet away, and then turned on the line filter... nothing smoking!!! Then I pressed the power button in the player, and it worked!!!

In all honesty, I only dared to do this on this Toshiba because the player is so inexpensive, so burning anything with this DIY attempt wouldn't be too much of a loss. Fortunately, it worked fine. Wow I really enjoyed this afternoon you have no idea. This is certainly a new hobbie I've found.

These mods I made are actually incomplete. Only today when going over the Vinnie Rossi intructions for these power supply mods I realized I should have ordered 2 capacitors of a specific kind (Panasonic X2-rated 0.47 microfarads), and I had ordered only one. Didn't want to install the only one I got, since these two capacitors are supposed to go in paralell with two stock capacitors (the blue rectangular ones) for better mains filtering. I chose to postpone that part until I have the other one and can install both at once.

The player is going through continuous play after the mods, for about an hour now. Will leave it like that a couple of days. Can's say much about sound differences, at least not yet, but I can say I'm just so proud and happy that the thing is working

[edit]Rehosting pics[/edit]
post #2 of 353
Nice work and pictures. I need to mod mine and now this makes me want to do it.
post #3 of 353
Nice work

I was wondering how much all your capacitors cost? Including the missing .47uF cap. Can't wait for your comparisons between your unmodded & modded player after you have burned-in your player well.
post #4 of 353
Thread Starter 
The missing one costs $2.35
The six capacitors I replaced cost all together $9.87.

My Digikey order was a total of $24.46. That includes $5 of handling charges, also the $4.26 opamp (OPA2604), and $2.96 for 12 other little capacitors for the audio board section of Vinnie Rossi's mods. I now think I won't do the opamp replacement part, but will try the Swenson mod instead.
post #5 of 353
I think you are hooked in a big way already.
Nice job, and thanks for the pics!
post #6 of 353
Quote:
Originally Posted by rsaavedr
The player is going through continuous play after the mods, for about an hour now. Will leave it like that a couple of days. Can's say much about sound differences, at least not yet, but I can say I'm just so proud and happy that the thing is working
Raul - congrats on some terrific work! Really great pics and words to describe the process, too. I think you are on your way to diy.

Now, how about building a weebl for me
post #7 of 353
Thread Starter 
Thanks all for the comments.

Gene at this point of my skill I can certainly tackle the weebl challenge, it might only take me a few trials, and probably a couple hundred years
post #8 of 353
I did these mods as well, including the X2 caps.

I also did all the digital board upgrades as well, including replacing the op-amp with an OPA2604. It really fixed the weak bass of the player and brought the midrange into that sweet Burr-Brown sound.

And like you said, you blow it up and you're out what, $50?
post #9 of 353
Which version of the OPA2604 do you use (there's 3 of them)?
post #10 of 353
Thread Starter 
Vinnie Rossi himself lists the Digi-key part number in his pages, its OPA2604AU-ND (8 SOIC packaging):
http://home.nc.rr.com/keihin/toshiba3950/vinniemods.htm

Xtreme4099 recommends the AD8620 instead, it seems to be a better opamp than the 2604:
http://www4.head-fi.org/forums/showt...3&page=6&pp=15

I'm still undecided between Swenson mod or opamp replacement.
post #11 of 353
Quote:
Originally Posted by rsaavedr
Vinnie Rossi himself lists the Digi-key part number in his pages, its OPA2604AU-ND (8 SOIC packaging):
http://home.nc.rr.com/keihin/toshiba3950/vinniemods.htm

Xtreme4099 recommends the AD8620 instead, it seems to be a better opamp than the 2604:
http://www4.head-fi.org/forums/showt...3&page=6&pp=15
Thank You very much!
post #12 of 353
Quote:
Originally Posted by rsaavedr
Xtreme4099 recommends the AD8620 instead, it seems to be a better opamp than the 2604:

I'm still undecided between Swenson mod or opamp replacement.
It's subjective, AD and BB parts sound different. I prefer the BB sound myself so I stuck with the BB chips. I've used AD8610/20 in various items and found it overly analytical in the higher frequencies and the soundstage separation didn't seem to satisfy me. I may have to get a BrownDog and put 2x OPA627 in that slot to see how that works compared to the OPA2604 next.
post #13 of 353
Thread Starter 
Quote:
Originally Posted by ITZBITZ
I've used AD8610/20 in various items and found it overly analytical in the higher frequencies and the soundstage separation didn't seem to satisfy me.
Ah, good reason to stick with the 2604 maybe. Burr Brown's have the rep of being smooth, never overanalytical, which is a good thing I think.

What do you think about the Swenson mod Itzbitz? I guess you preferred the Vinnie Rossi for some reason, and that's why you did that one. Wonder if you have thoughts against the Swenson mod. What I like about it is that it's much easier to do than the opamp replacement.
post #14 of 353
Quote:
Originally Posted by rsaavedr
What do you think about the Swenson mod Itzbitz? I guess you preferred the Vinnie Rossi for some reason, and that's why you did that one. Wonder if you have thoughts against the Swenson mod. What I like about it is that it's much easier to do than the opamp replacement.
I tend to prefer the accurate, low-distortion active electronics approach to the simple output capacitors with no feedback approach. I guess it's just a matter of school of though. I also don't feel the output from DAC chips was designed nor intended to go into the kind of load presented by the Swenson mod. It also results in a lower output voltage, which means more gain on the amplifier. Consider the Sonica, which has the output directly connected without an active filter network and the output voltage is pretty low compared to a standard 2V output.
post #15 of 353
Thread Starter 
Thanks a lot Itzbitz, that now makes me lean towards the opamp replacement.

I got the capacitor today, so I'm about to try finishing the power supply mods tonight. Here's a couple shots of my "shop" ready, another hour getting all of this ready:






Today I got tip tinner and solder flux from Radio shack (didn't use these the first part of my mods). Wish me luck. Pensacola is right now under a tornado watch. Unless with the storm I get some lightning, I might post some more as it goes. If I don't post for a few days you know what happened. So live from Pensacola, It's stormy DIY Thursday night!!!

[edit]Rehosting pics[/edit]
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