If it makes your ears happy, I'd consider it a job well done!

Well I mean, it sounds crappy even when new, so I don't think you can improve it too much. But it sounds indistinguishably from original card, so it is good...? 😁
Nothing beats EMU8k from the Soundblaster family in my opinion.

Well, they do say that you can't polish a turd!

Awesome!

awesome restoration job! (I would say it's rebuild actually!)

people are too picky nowdays, SB2.0 is still a nice card even today 🤣 yes it's not 150db 96khz but back at '91 is was great and certainly a great match for the crappy passive speakers we all had back then 🤣

Fantastic job! Would be happy see more pictures of your other projects as well! 😉

nice job! luckily mine was only missing the chips... there really is no way to not get remarked OPL2s though nowadays is there? ^^

^ no there are no ways maybe you get lucky and find 4-5 at some random seller or something... chinese remark them so they look new and are easier to sell
you just test and see if works and sounds correctly most of the times there is a real chip under the paint unless you buy 10x opl2 for 2eur where it literally is "too good to be true" 🤣

It seems to me like it would be more trouble than it's worth to fabricate new OPL2-compatible chips, unless one had access to the lithography of the original die. In which case... it's gray market, but it's still more or less the real thing -- just not sanctioned by Yamaha. If Yamaha has a problem with that, they're more than welcome to start pumping out genuine ICs again. As is often said, "piracy is a supply problem."

I'm not sure how I feel about resurfaced chips. On one hand, they look nice. On the other hand, I would kind of like to know the true lineage of the chip. But, I would rather take a resurfaced genuine chip that was salvaged from scrap parts than have someone buy up whole cards and pillaging them for their components.

PS., fantastic job on the restoration. I'm not sure I would've bothered, and it makes me happy to know someone did.

yeah it always makes me happy when someone saves nice old hardware from the scrap 😀

the situation about recycled/resurfaced chips is so-so... a lot of them were probably abused pretty hard during the recycling process (excessive heat/mechanical force), it's not like they take extra precious care to get an OPL2 chip out of something... they earn money purely by volume probably.

Okay, at least one person said that he wants to see more. So here it is 😁

This is the one which started it all. I got this offered from my friend for free. But knows his stuff since he resells old computer stuff for many, many years so I knew something's fishy. And sure it was. He doesn't like to work on anything so he threw this on me. And gosh darn it was a tough one. My first restoration job happened to be the worst as well. Why? The card was in some sort of bin which had dirt in it and it was frequently used as a toilet by a pack of cats. I mean - the stench was HORRIBLE!
First order of business was toss it into bucket of clorox and walk away for a week. It came out like this

After that I started disassembling

...to the point when there was almost nothing left. I wasn't skilled enough to pull the bus driver and the other chip.

Derusted the bracket

And then I had to wait for parts. But they came shortly after and I started rebuilding it back.

As a final touch, add C/MS chipset and ready to go!

But sadly, I can't find the video of a test. It was funny, but I have no idea where it went. I will hopefully find it soon and share 😀

krivulak wrote on 2020-02-02, 11:47:

[...]

great restoration work! kudos!

awesome, the world needs more of this ^^

Good job! I've got a bunch of cards I received in scrap lots that need work. Pretty sure I can repair them but I just haven't had a chance to mess with them.

By the way, those awfuly big 1uF 450V caps were eventually removed and replaced by more sensible 1uF 50V caps. So the bunch at the top of the card is not a problem anymore 😁

And I mean, I have a little bit of a free time so I will show you all one more. This started on an Retro Computers party. We were drinking with my friend and other friend started his "selling spree" as usual. I don't know how he managed to find these, but he had tons of stuff. But I mean TONS. He was for example selling 6 Gravis Ultrasound, 3 Pro Audio spectrums, 12 AWE32 and SB16 cards, 30 3Dfx Voodoos and more other stuff. And it was about 10-15 US bucks a piece. I mean, he totally destroyed the market in our country. Voodoos are worthless junk now 😁
Anyway, that's not what I wanted to talk about. What I wanted to say was he posted one sad broken SB 2.0 with destroyed bus driver. There was almost nothing left of it. But, only few of the solder pads were damaged or missing. I didn't have another one, so I first didn't want to buy it. It was 1 USD though, so the temptation was present. At that moment my friend told me that he has one smashed card that is pristine, only the CT1351 chip was broken. So I bought it. It came to me few days later and the condition was bad.

But remember, it was for parts only, so next step was removing the small chip and bracket and tossing the rest to the bin.

That was when I thought it will be easy. Then friend came with his card. The only thing what could be heard from me when I saw it was "Oh HELL NO!". I mean, look at it... 😁

So, the other card was a no-no. That meant the bus driver had to be removed from this card and transplanted on the other one. So, next order of business was as usual. Cleaning, removing broken parts, waiting on new ones.

There it was ready for reassembling. But one thing was still missing. The OPL2. I didn't have any on stock so I ordered some from China. Those never came in, the seller disappeared from ebay, but luckily I got my money refunded.

Moment from soldering. I love this paste, it really makes job easy. Soldered, cleaned, repaired some broken traces.

And there it was, all ready for testing, but I had still to wait on the OPL chip. It didn't stop me though, I tested it, but only in C/MS mode. And it played!

Few months later the OPL chips arrived. I was happy, immediately pulled one out of the packaging and stuffed it in the card. Aaand...?

Nothing. It made bunch of awful sounds and garbage came through the speakers. It seemed like it was playing only one tone and than froze on that tone. I was completely baffled. I tried to look on everything, nothing seemed to be the problem. Swapped some chips, nothing helped.

But then my friend, Rado (he is here on Vogons too, but I don't know his nick), sent me blueprint of the PCB. I was studying it a little, found wiring diagram for the BUS driver and found out that one trace was broken and I didn't notice that. The trace was nothing less but master clock for OPL2 chip. One patch wire later (it had to be fed through, it was a very painful process)...

And another SB 2.0 is fully working now! https://youtu.be/_y8bUQU43D8

You may say why I didn't use the OPL from that card from my friend. I actually wanted to, but then I took a look at it. I mean, I have never seen this version... YM3812-F and YM3014B-F seems to be the only difference, but man, that isn't quite common at least from what I know... Google found 0 pictures of that.

So, that means I am now commited to repair this thing. I am looking after some other SB 2.0 that has maybe broken DPS, like those destroyed by gold scrappers (they usually snip the 8 bit ISA connector) and can be salvaged for CT1336(A) bus driver, CT1351V202 and maybe LM393, but that is very common comparator, so no need to salvage it.