[BobM]

I've begun a modding project on this player. Right now I'm in the parts identification and ordering stage, but I'll share what I've got so far.

I feel that this $150 player (bought from J&R) sounds damn fine in its stock form, and so warrants modding to make it better. There is no doubt it is cheaply built - lots of plastic. But that doesn't change the fact that it still SOUNDS good. Oh yeah, this Toshiba player is actually a relabeled Samsung DVD-841.

Here's some links to my initial impressions of the player in stock form:

Link to 1st listening impression (pre mod):
http://db.audioasylum.com/cgi/m.mpl?forum=hirez&n=184328&highlight=BobM&r=&session=

Link to 2nd listening impression (pre-mod):
http://db.audioasylum.com/cgi/m.mpl?forum=digital&n=90757&highlight=toshiba+4960&r=&session=

Next up: details on parts selection.

Enjoy,
Bob

[BobM]

Mods to Toshiba SD4960 (part two)

Apparently the Toshiba SD4960 is actually a rebadged Samsung DVD-841. Looking at the service manual and schematic for the 841 I can confirm that this is true.

Here’s a list of cap locations, original and new values, that look like they should be replaced (based on scematics for the Samsung 841). These comprise most, if not all of the caps in the power supply and the DAC and SACD chips, but not the analogue outs since I’m doing a Swenson mod there. All replacement caps are Panasonic FC’s unless specifically stated:

KEY:
Board Location(s) - Quantity
Old Value
New Value  (Digikey part #)

PER10 - 1 cap
old: 82uF 400V
new: 180uF 400V (P6849-ND) [NOTE: used one of the mica's as a bypass cap under the board, didn't hurt - might help]

PES31,32,53,56,57, PEF21,22,23 - 8 caps
old: 100uF 25V
new: 120uF 25V (P10270-ND)

PES37, AE8,9,22 - 4 caps [NOTE: use old/original values for AE8,9,22, not the new/increased size]
old: 220uF 16V
new: 270uF 16V (P11200-ND)

PES36,58,59 - 3 caps
old: 470uF 10V
new: 560uF 10V (P11186-ND)

PCF11, PEF14 - 2 caps
old: 33uF 35V
new: 47uF 35V (P11232-ND)

PES33 - 1 cap
old: 1000uF 16V
new: 1200uF 16V (P11204-ND)

PES34 - 1 cap
old: 1000uF 10V
new: 1200uF 10V (P10226-ND)
   
PES35 - 1 cap
old: 47uF 50V
new: 100uF 50V (P10323-ND)

PES51,54, SAE1,2,3,5,6, SE1, AE7 - 9 caps [NOTE: use old/original values for AE7 not the new/increased size, I would also probably keep the SAE (SACD) caps the original value too if done again]
old: 47uF 16V
new: 100uF 16V (P11198-ND)

PE15 - 1 cap
old: 100uF 16V
new: 120uF 16V (P10244-ND)

N/A - 2 caps
old: N/A [NOTE: The sound was noticeably more open without these mica's from + to - across the RCA's. I didn't need them, but you might. Try it both ways. I used one as a bypass to the main PS cap instead.]
new: 300pF Mica (338-1065-ND)

The total cost for this parts list from Digikey was $27 plus shipping, so you won’t have to pay the extra $5 fee for orders under $25. Perfect.

I am also changing PCF01 and PCF02 from 100nF 275V X caps to .47uF 600V Auricaps. I will be doing the Swenson mod, removing caps AE10 (left) and AE20 (right) and picking up the + there. I connected the - side to the bottom of the board where the old RCS'a connect to ground. Wire to the analogue outs using 3uF 220V Sonicaps; I  bypassed with .1uF RelCap RT's that I have lying around. [NOTE: would probably go down to something between 1uF and 2uF without the bypass if done again - 3uF is overkill and not really necessary but using the RelCap bypass gives me the best of both options - high end clarity and deep bass.] and 300pF Mica caps for bridging [NOTE: Mica's now removed, they were not necessary in my rig and the clarity improved with them gone].

I would love to change out the rectifier diodes [NOTE: obtained 4A 600V Skottky TO-220 style as replacements, but they are not easy to find] also, located at PDS01,02,03,04 to faster and quieter diodes, like Shottky’s or Hexfred’s and such, but I can’t find anything at Digikey with the appropriate voltage values (1A 600V). If anyone has 4 appropriate diodes I would be most grateful. I do have some 1.1A 100V Shottky’s but I’m a bit afraid of using them given the 600V original values.

UPDATE: replace these 4 rectifier diodes with 4A 600V Shottky type. It's overkill, but some reports indicate that 1A replacements have blown in the Toshiba 3950 mods thread. These may be difficult to find, or you may have to purchase a minimum order size of 10 from Digikey. I used Cree CDS04060A TO-220-2 style. One had to go under the board due to space considerations. Shrinkwrap them or surround in electrical tape, since the backing is conductive. Be careful of diode orientation when installing - they do not all go in the same direction.

Enjoy,
Bob

[BobM]

Here's a picture of board with caps to be swapped marked with a yellow dot on top. Note, I couldn’t find the following caps on the board (PEF23, PES54, and SAE2 seems to be marked SAE7 on the board). Maybe there’s a small discrepancy between the schematic and production, or Maybe Toshiba did change some things from Samsung’s schematic?



(Hopefully this link works - please let me know if it is not visible to you'all, and how I can make it visible.)

All of the yellow dotted caps on the right side of the board are power supply related.

The ones at the top right are DAC and SACD related.

The two at the top left are not being replaced. Those are the 1st locations post DAC where I will pull the Swenson mod from.

So - I can't do anything else until the parts arrive.

I also got some Rat Shack gold RCA's that I will use for the Swenson output's. Anyone have a suggestion how to punch 1/4 (or slightly larger) holes in the chassis without the use of an aluminum hole punching device?

Enjoy,
Bob

[mcgsxr]

Interesting list of goodies, hope that it sounds good when done!

Could you drill the chassis, or are you afraid that you will "push too far" after getting through the chassis, and twist up the innards?  Drill press?

Mark

[speedcenter]

can't see your picture - I would really like to see a few closup pix of the guts of that player. Just an hour ago I opened a Panasonic DVD player I have here in the office and the layout in that box doesn't really make modding easy (transport is screwed right on the signal board...)  

do you have a modded 3950 you can compare this unit to in terms of redbook transport peformance? I've had pretty good success with my 3950 mods until I blew up the PSU trying out some fancy diodes  So while waiting for a new cheap 3950 on ebay to gut for parts, I have some time to consider future projects  


Peter

[BobM]

Yeah, seems like a broken link to the picture. Lets try it again:



or if not, then this direct URL should get you there:
http://photobucket.com/albums/v226/ptmconsulting/Miscellaneous/?action=view¤t=4960Board-premod.jpg

As for comparisons against the 3960 - no I don't have one. They are actually very different beasts. The 3950/3960 are designed and made by Toshiba. The 4960 is designed and made by Samsung and relabeled as a Toshiba. The 4960 is also a universal player.

Read my initial impression reviews for more details on the 4960. The Redbook sound is very good for a $150 player in its stock form. It compared very favorably with my modded DI/O, which compares well to other $1000+ players and DAC's. I'm expecting any slight congestion will be cleared up by my power supply mods, and the soundstage should improve greatly with the Swenson mod.

Enjoy,
Bob

[Woodsea]

This is great, I just bought the Samsung 841.  Do you know how I can make this player multi-region as well.  
Keep up the good work.  I am very interested in modding the bejeebers out of my player as well.
-Eric

[bubba966]

That seems to work...

[speedcenter]

or if not, then this direct URL should get you there:
http://photobucket.com/albums/v226/ptmconsulting/Miscellaneous/?action=view¤t=4960Board-premod.jpg

As for comparisons against the 3960 - no I don't have one. They are actually very different beasts. The 3950/3960 are designed and made by Toshiba. The 4960 is d ...

the link worked (and I hope that big old bug on images 2-5 wasn't in the box with the 4960 )

The board is very different from the 3950/60s (those have PSU "danger part" and signal boards in two pieces), but the build method is very similar. A large number of through-hole components on both means you can mod them pretty easily.

I'm not really interested in the universal player part, because I only have redbook CDs.  Based on what I see, the player has siginificantly more components on the signal board than the 3950's, but nothing really indicates that there are higher grade voltage regulators or anything else that spells out "quality"

Seems to me that all the extra circuitry gives you the multi-format capability, which is something I really don't care for.

I'll keep an eye on your project, but I'll probably be looking at modding a used Toshiba SD-9200 instead. Totally different animal at 35lbs - real power supplies, strong chassis - saves some money on those ends when you're thinking "serious mod"

Peter

[BobM]

It was actually a small-young bug. An emerging preying mantis about 3/4 of an inch long before the wings dried out and he/she flew away. Took those pictures in my backyard in the spring right next to the patio door.

A great natural adventure for my kids right in the comfort of my backyard - no bugs in my electrical components, even after I get done soldiering!

Enjoy,
Bob

[BobM]

Thursday mail came and went and no parts yet. Oh well - on vacation next week (getting out of the NY City blast zone), and need to pack. So the mods will have to wait till I return.

Sorry about the delay. To be continued ...

Enjoy,
Bob

[BobM]

OK, back from vacation. Nothing blew up in NY City and we managed to escape unscathed from hurricane Francis. On to the modding ...

Here's an image of the completely modded unit with some damping added. My transport looks very happy here.

http://photobucket.com/albums/v226/ptmconsulting/Miscellaneous/00ed38fe.jpg



More to come,
Bob

[BobM]

Damn, can't see the images. Don't know why they're not displaying for me. Hell, I can read a schematic and mod a player but I can't post a picture. Go figure. I'll include the URL's so you can link to them.

Here's a picture of a particularly tight cap placement. The replacement caps are a bit wider than the stock ones and the placement was very tight. I had to leave one cap stacked on top of the others. Now I know why the leads are so long when you buy these things.

http://photobucket.com/albums/v226/ptmconsulting/Miscellaneous/09ce8fb2.jpg



Bob

[BobM]

Here's 2 photo's of the Swenson mod. The first shows the pickup points for the positive lead. I used basic CAT 5E wire to run from the board to the caps.

http://photobucket.com/albums/v226/ptmconsulting/Miscellaneous/0fd514d8.jpg



Here's the second picture showing the outputs for the Swenson mod. I used 3uF Sonicaps here and 300pF mica's. I've used the Sonicaps before in my speaker crossover and found them to be more musical than Auricaps while still having all the transparency and detail. They're a bit less expensive too.

I placed these all the way to the left of the unit, on the other side of the transport to keep it as far away from the rest of the board and power supply as possible. It really is the only place where there's room enough unless you want the caps to be stacked on the board itself.

One word of caution. Make sure that your RCA's are not grounding against the chassis. You will need to insulate them front and back and on the threads, then double check it with a meter.

http://photobucket.com/albums/v226/ptmconsulting/Miscellaneous/5104fb74.jpg



I did implement the .47uF Auricaps power supply tweak as you can see from the first picture. The unit is outputting a signal - yes I checked. I finished up last night about 10:00 and haven't given it a listen yet. It's burning in as I write this.

I'm bringing it over to a friend's tonight to give it an audition. I'll be comparing it against one of the newer high end $2000 or so players that someone else just bought. My expectations are high.

Wouldn't it be a shame if this $150 unit with about $75 in parts and 4 hours of labor beats the $2000 unit in a listening session? And with only 24 hours burn in I expect it will get better yet.

Stay tuned ...

Enjoy,
Bob

[mcgsxr]

Thanks for the detailed log, and pics showing the various installations, it is cool to check out what has been done, and then read about the effects.

One question about the caps on the power inlet - are they basically one inline with + and - ?

mark

[BobM]

There is a fairly new power modification tweak that has been very successfully implemented in source components. Basically, you need 2 .47uF 600V Auricaps (about $25). You put these across the + and - where the power enters the unit, in parallel. So one on top of the other, in effect.

In the 4960 there are 2 X rated caps on either side of a small transformer. I replaced these caps with the 2 Auricaps, in effect doing the same thing as above, except that the small transformer is between the 2 caps. So ther is one Auricap right after the fuse, from + to -, then the transformer, then the second Auricap from + to - again.

You should be warned however. Most engineers and UL recommends only using X rated caps on power lines. These Auricaps are rated at 600V and should theoretically be OK, however they are not certified for use directly on a power line. So you're on your own if they cause a problem. I should also note that nobody to my knowledge has reported a problem with this modon the DIY boards that I visit.

Enjoy,
Bob

[mcgsxr]

Super Noob Question - so the two caps are in parallel with each other, and installed across the + to -, just inside the IEC for example?  That is what you are doing here?

I get you about the X caps etc, I have followed these points elsewhere, but never really seen the application.

Some people recommend this on the dedicated line, others suggest it on a component by component basis.

Any experience with this on a non-source component?  Do people do it for amps or anything?

Oh yeah, is that US$25?  Parts Connexxion etc?

Thanks again,

Mark in Canada

[BobM]

Most of thje caps came from Digikey, to the tune of $31 including shipping. I used Sonicaps from www.Sonicraft.com for the Swenson mod to the tune of $20 including shipping. I already had the Auricaps for the power supply bypass, but they cost about $25 from Partsconnexion.

I also purchased the technical manual for the unit so I could look at the scematics, that ran another $20, but you won't need that since I've listed all the parts locations in an earlier post. So my total layout was less than $100.

I've been breaking it in and giving a listen and will have very good things to report very soon. This in a comparison of the 4960 vs my Cal Labs/ART DI/O setup. I'm also going to see how it fares as a transport into my modded ART DI/O vs the 4960 as a stand alone. (Yes Martha, transports do contribute greatly to the sound in my experience, as hard as that may be to believe.)

Enjoy,
Bob

[BobM]

OK, the unit has been burning in on both SACD and CD for about 3 days now. There may be a wee bit more that can be eeked out with time, but it should be 99% there.

On Redbook CD's, comparing the unmodded 4960 to the modded 4960 (from memory):
 I can say that there is a definite improvement in a number of ways. The unmodded unit had good tonality, and that remains. It was slightly light sounding but has increased in body somewhat. For instance, before it would sound like a guitar or bass had more string, but now I also hear the wood of the instrument. The unmodded unit also had a bit of congestion on dynamic passages, especially evident on massed strings. Not anymore. This is all good and what should be expected when improving the power supply. The top and bottom ends are extended and inviting. The soundstage has always been very good - definitely not an in-your-face kind of sound that you would normally expect from a cheap player. This is the kind of sound that makes you smile, sit back and enjoy what you're hearing. Enjoyment of the music. I'm not one that enjoy's having to go into analytical listening mode to pick out subtle differences. That's what prompted me to say this unit was worth modding in the first place.

On Redbook CD's comparing the modded 4960 to my Cal Labs DX2-modded ART DI/O combo:
The sound is so similar in terms of tonality, soundstging (width and depth), ease and presence, top and bottom extension thyat it is very hard to tell the difference between them. There's only one area where I can say the Cal-DI/O combo stands out - it has more speed and definition, especially leading edge transients like you would hear on a plucked guitar or a snare-drum smack. It is only noticeable in a direct A-B comparison or else I probably wouldn't be able to hear it. However, being a nitpicker and being in an analytical listening mode, this quickness does tend to show a better sense of space around each instrument, making them stand out from each other in a more 3 dimensional way. Again, a subtle difference, and the Toshiba is no slouch in this regard. It has an ease and a very pleasant, listenable sound that doesn't lose any detail and also doesn't jump into your face.

On Redbook CD's comparing the Cal Labs vs. the modded Toshiba as a transport into the modded ART DI/O:
Hah! It's not the DI/O that is bringing more speed and definition to the sound, as I described above. It's the Cal DX2 as a transport. There is virtually no difference between the modded 4960 directly and the 4960 as a transport into the DI/O. Forget the virtually - there is no discernable difference at all. However, using the Cal DX2 as a transport brings out that leading edge transient speed. I wonder what in the circuit can be altered to improve on this speed. Maybe the clock? Anyone care to comment or make suggestions?

On SACD comparing the Toshiba to itself (same version of CD vs SACD):
This is what I was hoping for. The SACD playback truly blows away the CD playback, as it should. It is definitely more analogue like in it's ease and neutrality and listenability and liquidity. I really will need to compare the SACD vs. vinyl directly in the near future. I originally was drawn to this player because it was a universal player. The fact that CD playback is so good is an added bonus. Now I will need to find an expensive well regarded SACD player and see how this stacks up in a direct comparison.

There's one other review of a modded unit that was posted by FatCobra, on the audio asylum board. He compared this unit directly to a moddeed Toshiba 3950, for those who are interested in that match-up. In a nutshell, he's keeping the 4960 and putting the 3950 into retirement. Here's a link to his impressions:

http://db.audioasylum.com/cgi/m.mpl?forum=digital&n=90953&highlight=4960+fatcobra&r=&session=

Enjoy,
Bob

[BobM]

OK, another week gone by and some new "adjustments" have been made. I wasn't completely happy with one aspect of the presentation from the player either pre or post mod, primarily in the area of PRAT. Some may call it the "speed" of the player or perhaps the punch. One person said it is probably the difference between your typical op-amp dynamic and the slightly softer Swenson coupling cap type of sound.

A bit more forgiving than I'm used to and definitely enjoyable and easy to listen to, but just the one area where I think it could use some help. Now I'm really picking at nits here. This is a very good sound right now. And for $119 from JandR.com right now, a no brainer.

Anyway, I tried to bring some of this leading edge transient back into the picture. I changed the following. I reversed the following caps back to their original specification. They all feed the DAC chip. I have seen in the past where too much capacitance can make the chip sound slow, so back they went.

AE8,9,22 - 3 caps
old: 220uF 16V

AE7 - 1 caps
old: 47uF 16V

I also replaced the CAT5E wire from the board to the coupling caps with 30 guage silver coated copper & Kyner insulation. Wish I had some teflon coated solid silver wire around, but at $4-5 per foot for something between 24-30 guage (and you'll need just shy of 6 feet of this) I think I'll stick with this new wire for now. Silver interconnects also improved on the presentation over copper wire.

The 2 mica bridging caps on the RCA's also went bye-bye. Fatcobra said this helped open up his sound with minor or no problem with noise in the signal path. Now that they are gone I can confirm that I hear absolutely no pops or clicks or anything else that I could construe as noise that these things may have been preventing before.

So, the change in the sound. Definitely more open. Somewhat more detailed too, but still warm and inviting and laid back. The leading edge transients also appear to be better, but it is truly hard to tell without a direct A-B comparison. I can say they are still less than I am used to with my op-amp based ART DI/O.

Please remember, this is a subtle difference I'm extrapolating on, not a mind blowing one, so please keep that in perspective. Both units sound fairly similar in many ways. It's just the attack of the note that I'm trying to sharpen up a bit with the Toshiba.

I also played with AC polarity to see if it made any difference. It does. Mine works best in the regular polarity (big sized AC tong to the ground side of the outlet). I'm guessing here, but this probably has more to do with the orientation of the .47uF Auricaps across the AC input than anything else. If you put their red lead on the + and the green one on the - side then you should be OK and have the same results as I did with polarity.

So, how to take this more in the same direction? Don't know. I need your suggestions. Wish I could get four 1A 600V fast recovery diodes and rebuild the rectifier bridge, but I haven't found a source that doesn't want a minimum order size that makes this prohibitive.

Any thoughts and suggestions?

Enjoy,
Bob