Toshiba 3950 power supply mods (with pics)
May 13, 2004 at 1:47 AM Post #32 of 353
Quote:

Originally Posted by rsaavedr
Anyway, I am actually more curious to compare this modded Toshiba with other players and brands, actually mid-end and higher end players, and see what differences I can perceive.



Do a blind test against a Meridian or other high end player and see if the Meridian owners can tell which one is which
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May 13, 2004 at 2:44 AM Post #33 of 353
Quote:

Originally Posted by meat01
Do a blind test against a Meridian or other high end player and see if the Meridian owners can tell which one is which
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Man expecting it to match a Meridian is probably just a bit over-optimistic an expectation
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May 22, 2004 at 6:33 AM Post #34 of 353
Blackgates arrived today!!, tomorrow will be another DIY fun ride finishing the audio PCB mods. I will post "Before", and hopefully successful "After" pics of the dreadful opamp replacement. Wish me luck!
 
May 22, 2004 at 4:59 PM Post #35 of 353
Quote:

Originally Posted by rsaavedr
Blackgates arrived today!!, tomorrow will be another DIY fun ride finishing the audio PCB mods. I will post "Before", and hopefully successful "After" pics of the dreadful opamp replacement. Wish me luck!


Have fun! Hoepfully you can extract some inspiration from my Godzilla mods to the EMU!
 
May 22, 2004 at 7:44 PM Post #36 of 353
Stock Opamp is out!!! I did it! I did it!
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Darn little thing was fighting hard to remain there, what a grip. After lots of heating and wickering, then a final soft twisting with pliers left it loose. Here some pics.

After removing six caps surrounding the opamp. I should have put a ruler nearby for scale, take into account each side of that little square of an omamp is just 3/16 of an inch long. On my laptop screen, this picture seems to show about 2x the real scale. Check out how close some other SMD super-tiny components are to the opamp legs. Heating there is quite risky because some of those tiny satellites could have gone loose.
1582bgopamp_mod0002.JPG


After grip of the opamp had been defeated:
1582bgopamp_mod0003.JPG




And now to place the new opamp over there, and then the black gates...
[edit]Rehosting pics[/edit]
 
May 22, 2004 at 10:08 PM Post #37 of 353
Mods completed successfully!!!! The new Burr Brown op-amp, and the little Black Gate capacitors already going through break-in. To me sounds better already, without break-in. Sounds as smooth as before, but somewhat "richer", and bass/sound seems a bit fuller. But I would need another same player with the previous version of the mods for A/B comparisons, or a stock, otherwise, placebo nonwithstanding. Anyway, sounds very nice. Here some pics of the final stage of the saga:

The tiny Black Gates caps, and the Burrbrown opamp next to the tip of the ruler. Check how tiny. To the top right is the older opamp upside down (still knocked out from the fight
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):
1582bgopamp_mod0004.JPG



Here's the Burrbrown OPA2604AU-ND in place. Soldering the tiny legs ended up (for me) easier than desoldering and removing the stock opamp. First I fixed the opamp to the board with a tiny glob of "white tack", then it was a matter of touching the legs with the soldering iron tip having on the tip a tiny bit of solder already:
1582bgopamp_mod0005.JPG



Here's a view after soldering the blackgates and the other caps I had removed for easier access to the opamp:
1582bgopamp_mod0007.JPG



Here's a top view:
1582bgopamp_mod0008.JPG



I'd like to say thank you to Vinnie Rossie for publicly sharing the specs of his mods, and to all Headfier's who helped me with feedback for putting together my beginners DIY kit, and with procedural suggestions. This was really a ton of fun!!!! Thanks!!!
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Second project: a Kevin Gilmore's Dynahi this Summer!
[edit]Rehosting pics[/edit]
 
May 25, 2004 at 5:46 AM Post #38 of 353
After 48 hours of continuous break-in, the player is pouring a fantastic sound. Before elaborating on my own impressions, I'd like to take the liberty to quote here Vinnie Rossi's own comments on the sound of the Toshiba 3950 after his mods:

From http://home.nc.rr.com/keihin/toshiba3950/vinniemods.htm
Quote:

The bass is very tight, fast, and clean. Compared to the stock bass, there is some more of it (just the right amount IMHO) and the quality of it has improved a lot.

The highs are now very liquid, detailed, and a pleasure to listen to. There is absolutely NO LISTENER FATIGUE to report here folks, I'm talking about beautiful treble that is very similar to the ack!dack's. It is not rolled off in any way in my system, and it is a joy to listen to! Much improved over the stock treble (changing to the black gates and removing that crappy JRC dual-opamp and putting in the Burr Brown OPA2604 really did the trick!) As mentioned before by Jon Risch, the OPA2604 is a perfect balance between the tube and solid state sound. I agree 100% on this one.

Soundstaging and depth reproduction are superb to me as well. The whole soundstage is push back a bit more than stock (which is what I wanted BTW), and the overall sound is quite 3D. The congestion during complex passages that I noticed with the stock unit is all gone. I think the combination of using lower ESR caps, and using the Black gates and Burr Brown Opamp fixed this problem the most.



Three friends were visiting just now, and we were listening to the modded Toshiba with my speaker rig, playing Audioslave, Rage Against the Machine, Madonna, and some Venezuelan guitar music by John Williams. To my friends the modded Toshiba has bass almost identical to my Sacdmodded Sony NS500V (playing cd's), which wasn't the case for them with the pre-modded Toshiba -they had also come by to compare these players before my finishing the audio mods. I differed on that assessment with respect to bass. Overall the two players sound quite similar in the lows, fast, punchy, and strong, with authoritative slam (the Azur 640C had even more slam than the Sacdmodded Sony, but not too much more either). To me the Sony has a very tiny bit slammier bass than the modded Toshiba in the very lowest frequencies. This is not apparent always of course, depends on whether the song being played goes low enough to expose that small difference. For instance, Madonna's Die another Day is one in which I could perceive this difference. Incidentally, that's one of my bass testing tracks. Sitting at the sweet spot (what my speaker rig is calibrated for) is where I could tell the difference better; standing by and a few feet off, then I couldn't. The "thumps" in Madonna's "Thump-clap-thump-thump-clap" seemed to be a bit bigger/heavier coming from the Sony, as if a slightly heavier giant had taken a mighty step. With the Toshiba it was also a mighty giant taking the step, but probably a few pounds less heavy of a giant. Something along those lines. Don't get the impression the modded Toshiba is at all lean on the bass. Even stock it was stronger than the stock Sony, and these mods made it even stronger. It is powerful and rich and with SLAM.

Speaking of richness, in the upper bass/midrange region, the Toshiba sounds a bit richer and fuller, while the Sony sounds somewhat drier to me. My friends looked at each other with no comment when I made that assessment. I haven't heard the Ack! Dack, but wonder if that richness/smoothness in the Toshiba is among the things Vinnie found particularly alike in them. With respect to treble, the mods did "open up" a bit the treble in the Toshiba, it sounds similar enough to the modded Sony. My friends agreed, treble-wise not much difference, at least with the music we were playing. Actually to them no player appeared brighter or bassier than the other in any significant way. The Sony keeps sounding a tiny bit brighter to me (filter in Sharp mode btw), but not sure if it's true treble difference, or a result of that richness balance difference I perceive in the upper/bass-midrange. Overall both are very non-fatiguing and nice sounding for sure. I should clarify, the comparisons were done using exactly the same interconnects (Monster Interlink 400 MkII, actually all my speaker rig described in my profile). So it wasn't a quick A/B switching though, but playing part of a song with player A, then stopping, reconnecting the ic's, and then playing it with B.

Which one is closer to high-end? Well, cost-wise, the modded Sony for sure
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Sound-wise, I really don't know. Would need a higher end player as a reference to compare them to and see where they stand. To my ears, what I'm calling a "richer" midrange in the Toshiba has a special appeal though, vs. the probably more analytical or drier sounding midrange in the Sony. Despite the tiny bit more slam in the Sony, what I'm calling "dryness" in it makes voices sound somewhat a bit thinner compared to how they sound from the Toshiba: a bit richer and fuller, and smoother...

Most likely I'm abusing my use of English to try to express my impressions, and I compared using my speaker rig, not the Grace 901 (courtesy of Agile_one) and my 650's+Zu, which I'm planning to use after more extended break-in of these mods. So take everything with a pound of salt, YMMV. So far I think these differences I perceived are in the domain of taste-dependence rather than true substantial differences in sound quality. Given my exposure and limited experience, to me these two modded players sound both *very* good, and in a similar league.


PS. Would like to take the opportunity to say special thanks to Rick for his Sticky DIY links, to Tangent for his pages and feedback, and to Itzbitz and Morsel for their feedback and suggestions. Thanks very much all!
 
May 25, 2004 at 6:35 AM Post #40 of 353
Mclaren I'm really not the person to ask. I really don't know what each cap does at all in the circuit, Vinnie Rossi and Swenson know about some of them somehow, I understand official schematics for the circuit in this player are still to be found.

Some of those caps on that board are probably related to the video circuitry instead of audio, so for audio improvements I wouldn't think changing all of them would help. I have thought about the fat one on the top-right though, next to the RCA outs black block. Since that stock cap is already quite big, maybe if it's related to audio that might be a good replacement candidate.
 
May 25, 2004 at 2:22 PM Post #41 of 353
That fatty is next to a bunch of regulator chips, so it's likely a power supply filter cap or reservoir cap. I don't know how much that can help to upgrade, but hey, at least your caps would match in color.
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I'm stopping by to see Phil at Cimarron Technologies this week to get a SOIC BrownDog adapter to allow me to use two OPA627's instead of the OPA2604. I'll report back on the results when I get it done.
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May 25, 2004 at 4:32 PM Post #42 of 353
Quote:

Originally Posted by ITZBITZ
That fatty is next to a bunch of regulator chips, so it's likely a power supply filter cap or reservoir cap.


Ah yes makes sense the fatty is power related. The power cable coming from the power supply board connects to this other board through the white connector behind the raw of thinner caps on the top, right there very close to the fatty. Hmm, seems then it might represent a good addition to the power supply mods, to replace this fat cap here on the audio board power section with a better cap, well unless this stock cap is good enough already.

Looking forward to your impressions after alternating opamps Itzbitz.
 
May 25, 2004 at 5:12 PM Post #44 of 353
Quote:

Originally Posted by smeggy
I'm also going to put it into a ParMetal case with a Front Panel Express faceplate and tray cover. It'll be remote control only after that.
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You'll have to post some pics please, to replace the case of a player sounds like a very interesting project on its own actually.
 
May 25, 2004 at 5:36 PM Post #45 of 353
Yeah, well it *has* to look better than the sucky case Toshiba supplies. I've already made my headphone amp. I can't recall if I posted any pics though. It's a Tripath chip amp with a nice TKD pot and a Jan Mier crossfeed circuit going into the Tripath and then out through an Antique Sound Labs headphone transformer. Bags of dynamics and overhead. Sounds really nice and easily beats anything else I've tried. Cost next to nothing too (relatively speaking) for the level of sound quality I'm getting. Complete custom case from plans I sent to Frontpanel Express.

Original 3d rendering of my design.
http://home.comcast.net/~garybutcher/ampsmall.jpg

Real stuff:

Top of the sexy case
http://home.comcast.net/~garybutcher/top.jpg

Back
http://home.comcast.net/~garybutcher/back.jpg

Front
http://home.comcast.net/~garybutcher/front.jpg

ASL headphone transformer
http://home.comcast.net/~garybutcher/ASL.jpg

Stripped out Powerwave
http://home.comcast.net/~garybutcher/board.jpg

All the Bits
http://home.comcast.net/~garybutcher/all.jpg

Crossfeed circuit for headphones
http://home.comcast.net/~garybutcher/crossfeed.jpg
 

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