The last available source:
http://www.gameroomrepair.com/ICparts/ICparts.htm#SC01A

You're better off just buying a new board from Swemmer given the price of those chips from GameRoomRepair.

Fred might have the last stock of those chips and he doesnt sell them outside of his boards, and for good reason. I highly recommend his sound board. Had good status LEDs, spot for an external ground link, AND a line out which is fun. I have a 1/4” output on the bottom of my Black Hole cab that I can hook up to an external amp or my audio interface for streaming.

From what I was reading, its an analog chip which is the problem.

Seems like the prices are getting to the point to justify reproductions. This one has been talked about and experimented on numerous times and it always seemed to come back to this. Fingers crossed someone actually makes one and makes it available.

Would be better off and cheaper just making a replacement board with common tech.

The sound triggering is not complex on this game, just five? lines being grounded in various combinations if I remember correct. Factory test of the board is literately just grounding the pins to trigger a sound.

I guess it wouldn’t be impossible to get clean samples of each sound and recreate a board with modern chips and triggering, but at that point there’s no reason not to just buy Fred’s board which is extremely high quality.

That's assuming he still has stock of SC-01 chips..

That is the problem and once the chips are gone..

Or if the SC-01 goes bad and then you have an expensive paperweight.

Fred's boards are not the weak point.

Yup.
Lisy is developing FGPA MPU boards now. I wonder if it's on the cards to implement the SC-01 emulator into a replacement FPGA sound board.

Yes. Replicating or emulating the chip is not so simple as to just sample the 64 phonemes and play them back at request. The analog parts handle the transitions between different phonemes, making the speech sound more "natural" (as if). Anyway, with just using the sampled phonemes, the resulting speech is even less natural.

I think a wav trigger board could be used if the sounds were recorded to that format .
The triggering crossover would be the issue

I have made a system80 replacement soundboard based on FPGA and a MP3 Player.
The FPGA does emulate the original Soundboard Hardware and is running the roms from the SD card.
In case of Soundboards with speech ( SC01) speech sequences are played by the MP3 Player from a wav file on a second SD card.
All other sounds are coming direct from the FPGA (Delta-Sigma audio DAC)
In theory it would also possible to let the FPGA produce the phonems by implementing a speech synthesizer
but the MP3 Player is much easier to implement and gives the oportunity to use own (better) speech.

As all the other projects on my website I do provide all information for free as a DIY project.
If you want join testing let me know.
Further information here: https://lisy.dev/gosof80.html

GOSOF80 v2.1 (resized).png

Wow.
Question, I presume the main SD card just contains the sound ROM image? If yes, is it possible to just upload it into the FPGA chip as part of the FPGA image? i.e. to eliminate the primary SD card?

Now we are getting somewhere.

Yes, thats possible, it would be one FPGA image for each soundcard.
However I choosed the SD card solution to avoid copyright problems with Gottlieb rom code.
With the rom code on SD each user can use his/her own rom code and I do not need to include it in the FPGA image.

However once I have a stable version I will publish the source code. With that you will be able to compile your own image with the rom code included.
( The compiler is available for free and I can explain what needed to be changed in the code and how you need to prepare your rom code)

Excellent!
Sometime next year my Black Hole will come home from storage and I'd like to build your "gosof80" if it's ready.

Keep up the great work!

Do you know for sure your SC-01 chips are bad? Those are usually reliable chips. Only ones I’ve ever had to replace were do to reversed polarity or extreme over voltage.

Years ago I used a Speakjet as a replacement for the SC-01 chip. Used an SX28 processor as the translator. Had a write up about the project in SERVO magazine.

I still have some spare SC-01A chips. If anyone really needs one to get their Black Hole or Volcano going I could part with a couple for less than the game room repair site.

Wow...that's really great--I've been hoping there could be some path towards a sc-01 replacement, and this comment alone has been the most practical thing anyone has said on the subject in years.

Would you perhaps be interested in adapting the work for use in pins that use the sc-01?

I created this thread a while back trying to hunt for possible options:

https://pinside.com/pinball/forum/topic/sc-01-speech-synthesizer-replacement

Is there more that you can share about your work with the speakjet chip?

I have my old article online here:

https://www.robotworkshop.com/robotweb/wp-content/uploads/servo200712_HERO_Speech_translator.pdf

I was going to shrink it all down and put on a small plug in hybrid module to go in the socket in place of a real SC-01A. Would probably need to revisit that project and check on the surface mount Speakjet chips.

Back when I did that project I was primarily doing it for the early 80’s robots but it would apply to any game or device that used it.

Keeping a spare SC-01A aside in case I want to add speech to my Haunted House and can eventually try my old board from the article in that too.

Robert

PM Sent

Great writeup Robert. Thanks for sharing.

I have to ask, did the Speakjet chip audio sound like the Vortex chip audio? I'd love to hear what it sounds like if you have a sample saved.

I saw someone here say they don't see the SC-01 chips go bad but in the arcade world they do quite often. Wizard of Wor and Gorf use this chip and I've seen at least half a dozen bad chips in the past decade or so. A true compatible replacement(that at least sounds like a relative of the Vortex chip) would be great to have available.

[edit]Just went back and re-read some of the thread and saw it was you who posted this... and I agree about defective power supplies overvolting and kill the SC-01 chips. I've had that happen to me once and to the arcade I help out at once... both on Gorf machines.

Not to mention that two of the backbox connectors on Black Hole are keyed alike, which will shock the sound board's 12v input with 60v. Embarrassed to say how I know this.

Mine just randomly failed. Board checked out, voltages spot on. Replaced chip and was back in operation.

It looks like there have been a couple SC-01A chips pop up on ebay. If anyone needs one I'd suggest setting up a watch list for them.

Just picked up a Volcano to sit next to my Haunted House so now I have a machine that is running an SC-01A speech chip. May dig out my old board for the plug in SC-01A replacement and will listen to see how it sounds plugged into Volcano.

It looks like game room repair sold the last of their SC-01A chips. In a pinch I could probably part with a spare but anything beyond that will need an alternative solution. Will need to dig out my old SC-01A emulator and see if it works in the Volcano and sounds the same. If I do I'll tweak the code to log the phonemes sent to it. Would be cool to hear my old HERO robots say some of the EXACT phrases in the old Gottlieb machines.