Hi,
I recently needed to purchase an AY-3 8912 sound generator chip for one of my cpc, and found out that prices gone INSANE, the cheapest i could find was ~25euros/piece! :o So,i've decided to design an adapter, in order to use the MUCH,MUCH cheaper AY-3 8910 (you can find it for ~2euros/piece or even less, on ebay or aliexpress).
So, this is the adapter board:
ay3_8910adapter3.jpg
And here is the gerber files (https://www.dropbox.com/s/3njnpasra51mcdp/ay3%208912_8910%20adapter_gerber.zip?dl=0) for anyone interested to build it.
Adapter dimensions is ~5,3cmX3cm so it should fit inside any Amstrad cpc.
Adapter provides a 10pin port, to access power supply+2nd I/O port of 8910, and an optional pull-up resistor network, if needed.
Mind also that adapter is currently untested, but if you happen to need an AY-3 8912 chip, you can try this alternative.
In any case, this might be the only feasible option in the future, if prices of AY-3 8912 continue to rise... ::)
I revised the board to fit better on a cpc 6128 board. Gerber files updated too.
I suggest to swap VCC and GND in case you are using a DB9 ribon cable for the external GPIO, else the GND signal will be lost at pin-10. (sure, nothing wrong if the full pins are used by plugging something on the connector)
Quote from: TotO on 11:48, 21 August 22I suggest to swap VCC and GND in case you are using a DB9 ribon cable for the external GPIO, else the GND signal will be lost at pin-10. (sure, nothing wrong if the full pins are used by plugging something on the connector)
Done! ;)
Nice!
I have expected that you will avoid the extra via. ;D
Quote from: TotO on 11:58, 22 August 22Nice!
I have expected that you will avoid the extra via. ;D
Power traces are too wide to cross between pin holes, so using via was the only way... ::)
No worry, it is what I have expected. ;)
Hi, i have a few questions as i recently replaced the membrane of my CPC6128 and still have issues so i thought i would try the AY chip next.
1. if you are not using port B can that be left blank?
2. I assume for this you remove the current AY-3-8912 IC and then connect between where the IC sat on the motherboard to eh relevant pin position on this PCB and then install the AY-3-8910 IC in this PCB??
3. are you having the PCB made and could i purchase 1, i did find one place that would make 5 and ship for $10.44, but at that price when you add the cost of the AY-3-8910 IC and connectors etc, it may be as well just getting the AY-3-8912 IC
Thanks
Stu
I just ordered 5 pcb's (the smallest quantity i could order) with delivery it cost me £8.33 and i have ordered 1 AY-3 8910 IC for £2.73. delivery is in 7-10 days so i will let you know.
so in total £1.66 for the PCB and £2.73 for the IC total cost is £4.40.
if anyone in the UK needs one of the spare PCB let me know.
Thanks
Stu
Quote from: stulish on 17:33, 01 September 221. if you are not using port B can that be left blank?
Sure, but it is a shame to lose it. ;D
I have suggested to be a R2R 8-bit DAC mixed with the AY audio.
one other thing what is the pull up resistor there for, also what part number would that be? :picard:
The pull-up is optional. It is a 2.2 kOhm 8+1 resistor network.
I have done that (untested) to be tested on a 464/664 last week. Probably VCC and GND on the schematic are not required (available through the socket), but it is a commodity to have the good board and schematic visual.
Hi all i just found:
Adapter PCB for AY-3-8912 sound chip to AY-3-8910 (https://www.tindie.com/products/semachthemonkey/adapter-pcb-for-ay-3-8912-sound-chip-to-ay-3-8910/)
cost is $3 from a UK seller based in Nottingham, this doesn't have the second port etc
Regards
Stu
@stulish Sure, no second port... It is the invert of what you require on CPC. ;D
So i have replaced the AY-3-8912 IC in my CPC6128 with one from a CPC464 (it wasn't easy un-solderig the IC's and then re soldering).
anyway the same fault remains with the CPC6128 so i now dont think the AY chip was to blame.
the errors i see on screen are different with the two membranes (old membrane and new replacement membrane).
I have updated a video of with each membrane fitted pressing each button on the keyboard in turn so you can see the difference, the new membrane has more keys not registering so i am thinking it is faulty and it was also delivered in a box where it was folded over quite badly (i would have expectd something to keep it flat.
the link for the videos are below:
This video is of the new membrane, at the end i show the old membrane and the poor repair attempt that had been made (this made me think the membrane needed replacing):
The video below is with the old membrane installed:
Let me know if you have any thoughts as to what to try next.
Thanks
Where to get such a new CPC6128 keyboard membrane today?
I got it from a company called SINTECH in Germany, SINTECH Shop (https://www.sintech-shop.de/en/replacement-keyboard-membrane-new-production-for-amstrad-cpc-6128/a-10822)has these for 32.73 euro, however because i am in the UK they couldn't ship to the UK but i could buy from their ebay store (at more cost). overall it cost me euro (48.77 + 4.39) 53.16 with delivery from eBay (https://www.ebay.co.uk/itm/385004740274).
hopefully they will get back to me about either how to test or a replacement item.
I just put the 6128 AY-3-8912 IC into the CPC464 and the keyboard works fine on that so it wasn't the IC for me.
Regards
Stu
Quote from: GUNHED on 16:53, 04 September 22Where to get such a new CPC6128 keyboard membrane today?
I got it from a company called SINTECH in Germany, SINTECH Shop (https://www.sintech-shop.de/en/replacement-keyboard-membrane-new-production-for-amstrad-cpc-6128/a-10822) has these for 32.73 euro, however because i am in the UK they couldn't ship to the UK but i could buy from their ebay store (at more cost). overall it cost me euro (48.77 + 4.39) 53.16 with delivery from eBay (https://www.ebay.co.uk/itm/385004740274).
hopefully they will get back to me about either how to test or a replacement item.
I just put the 6128 AY-3-8912 IC into the CPC464 and the keyboard works fine on that so it wasn't the IC for me.
Regards
Stu
WoW! Not cheap. But thanks for the info.
Hope you get your system running in the way you want. :)
Quote from: GUNHED on 14:40, 05 September 22WoW! Not cheap. But thanks for the info.
Hope you get your system running in the way you want. :)
they produced a whole new batch for the 6128 and the Plus range. When thinking about that and that they need to make a profit, the price seems to be fair.
.
Quote from: eto on 14:51, 05 September 22Quote from: GUNHED on 14:40, 05 September 22WoW! Not cheap. But thanks for the info.
Hope you get your system running in the way you want. :)
they produced a whole new batch for the 6128 and the Plus range. When thinking about that and that they need to make a profit, the price seems to be fair.
The price was not cheap, but as
eto supporter said they have to make it economically viable after creating it and then having them manufactured etc, so i was happy to pay to get my system working properly. Hopefully they can get to the bottom of why the new membrane isn't working, they are answering emails and i have sent them the video/pictures so hopefully they can help, i had a response from them:
QuoteI see you photos of packaging and this packaging is according to our rules. The membranes are of an exellent quality. No doubt there is a problem, but the reason for the problem is not that the membrane is slightly bent, this should have no effect.
When you send me your video (or link) I can maybe sort out the problem. In a previous case, the membrane needed a little bit of air between the layers, so the customer pinned a small hole at a place where are no electronic lines and it solved the problem. It might also help to roll and enroll the membrane a bit.
so it looks like they have had troubles before that they have managed to overcome, hopefully i will get this working and can play my old games on the original hardware and not emulated :)
i just found this webpage (https://pelrun.github.io/cpc-schematics/index.html) that shows the top and bottom of the CPC motherboard and you can click points on it and it will show you where it is connected to, this could be really useful :D
Quote from: stulish on 00:21, 06 September 22i just found this webpage (https://pelrun.github.io/cpc-schematics/index.html) that shows the top and bottom of the CPC motherboard and you can click points on it and it will show you where it is connected to, this could be really useful :D
Yes, it is related to another cpcwiki topic, done by
@pelrun :)
I have had a look at the new Membrane using my camera (zoomed in), and as there were so many keys not working looked at the areas where all tracks are close (the ribbon).
it looks like there are cracks along the tracks along a piece of strengthening backing (see images)
I have sent the images to the place where i purchased the membrane from to see what they think.
Would it be worth adding a socket for an optional second soundchip? Either another at or a sid... or both.
The Adaptor PCBs arrived tody and look good :)
Originally i thought i could use pins to go directly from the pcb into the motherboard with the new AY-3-8910 IC fitted but this will not work as the PCB will foul on the capacitors on the right of the photos.
so i think the only way to install will be to use individual wires from the PCB to the motherboard.
Regards
Stu
Quote from: stulish on 22:55, 13 September 22Originally i thought i could use pins to go directly from the pcb into the motherboard with the new AY-3-8910 IC fitted but this will not work as the PCB will foul on the capacitors on the right of the photos.
so i think the only way to install will be to use individual wires from the PCB to the motherboard.
Regards
Stu
Thanks stulish for being a "beta tester" for the board! :)
Now, you think that if i cut the part in red rectangle:
8910_3.jpg
board will fit on AY 8912 Socket without bumping on the caps? Also, apart from the caps, is there any other place of board which might not fit and need a bit "Triming" too?
@stulish , you think this will fit?
8910_4.jpg
Quote from: ikonsgr on 21:22, 15 September 22@stulish , you think this will fit?
8910_4.jpg
I think the only way to make it fit would be to turn the 8910 IC 90 degrees so it sits above the IC's below, my very poor drawing shows what i think, but not sure if this is achievable?
Just as an update after finding the cracks in the tracks bu the connector, the company are sending me another membrane (hopefully this will work fine).
:)
Just a warning : piling up IC/PCB where the keyboard membrane wraps is a not a good thing. There is less than 0.5cm for the membrane to wrap and there is a chance of stressing/damaging it there.
The only way to avoid this stress is to make sure the membrane wraps toward the outside of the CPC instead of the inside as it would naturally do.
Quote from: zhulien on 01:52, 09 September 22Would it be worth adding a socket for an optional second soundchip? Either another at or a sid... or both.
A second AY wouldn't be too difficult, but it would need a little more than just a socket. You'd need separate addressing from the 8255. Adding a SID would be rather complicated. It would need a lot of additional circuitry.
Bryce.
The goal is to replace a defective soundchip with something not expensive.
If you start to add extra chips, that mean you have the money to buy the 8912 alone. ;D
Quote from: TotO on 12:19, 18 September 22The goal is to replace a defective soundchip with something not expensive.
If you start to add extra chips, that mean you have the money to buy the 8912 alone. ;D
You can buy a box of AY's for the price of a SID!!! :D
Bryce.
Quote from: Bryce on 08:24, 19 September 22You can buy a box of AY's for the price of a SID!!! :D
True. For the price of the SID you can buy a Play2CPC, a better deal for the CPC users.
What is funny is the speculation around the SID chip finally not so rare to find.
Get a LambdaSpeak FS for the price of the SID and enjoy all you miss when using a SID. ;D ;D ;D
Quote from: stulish on 18:12, 17 September 22I think the only way to make it fit would be to turn the 8910 IC 90 degrees so it sits above the IC's below, my very poor drawing shows what i think, but not sure if this is achievable?
I don't think this arrangment would fit either. It would require for the hole 40pin socket to be placed under the 28pin socket, which surely will hit onto CRT6845 chip.
Anyway,i believe the indentation of the new design would fit, maybe by pushing a bit the cap. I also trim it a bit more: https://www.dropbox.com/s/wc9q8cd3ujkkbnm/8910_8912.jpg?dl=0
Anyway this is the new gerber files for anyone wants to try it: https://www.dropbox.com/s/3njnpasra51mcdp/ay3%208912_8910%20adapter_gerber.zip?dl=0
Quote from: zhulien on 01:52, 09 September 22Would it be worth adding a socket for an optional second soundchip? Either another at or a sid... or both.
I guess that managing a shift register with the extra GPIO port of the 8910 you could control any number of extra chained AY's.
Quote from: ajcasado on 08:51, 22 September 22I guess that managing a shift register with the extra GPIO port of the 8910 you could control any number of extra chained AY's.
Sure, but il will be slow to control extra AYs requiring to access PPI->AY->AY. (and probably some logic for the data bus)
And currently, I can read that is difficult to physically fit one 8910. ;D
Quote from: TotO on 09:07, 22 September 22Quote from: ajcasado on 08:51, 22 September 22I guess that managing a shift register with the extra GPIO port of the 8910 you could control any number of extra chained AY's.
Sure, but il will be slow to control extra AYs requiring to access PPI->AY->AY. (and probably some logic for the data bus)
And currently, I can read that is difficult to physically fit one 8910. ;D
Totally agree, but it could be a nice experiment in case you have to replace the ay from your CPC.
Quote from: ajcasado on 09:18, 22 September 22Totally agree, but it could be a nice experiment in case you have to replace the ay from your CPC.
The more easy and cheap is to add a R2R DAC on the GPIO B, under the 8910 socket to replay PCM sample like the Digiblaster.
If people would like extra audio channels, it already exist some expansions for that (PlayCity, LSFS, Willy, Play2CPC, more?) and the free room inside a CPC can probably allow to embed some of them using an internal expansion ribbon cable, if not external.
Quote from: TotO on 09:28, 22 September 22Quote from: ajcasado on 09:18, 22 September 22Totally agree, but it could be a nice experiment in case you have to replace the ay from your CPC.
The more easy and cheap is to add a R2R DAC on the GPIO B, under the 8910 socket to replay PCM sample like the Digiblaster.
If people would like extra audio channels, it already exist some expansions for that (PlayCity, LSFS, Willy, Play2CPC, more?) and the free room inside a CPC can probably allow to embed some of them using an internal expansion ribbon cable, if not external.
The DAC thing is a very nice idea. :o
Quote from: ajcasado on 09:37, 22 September 22The DAC thing is a very nice idea. :o
Hehe. You have liked the idea on September 1st. :)
Here the next post:
(require to test the audio mix)https://www.cpcwiki.eu/forum/index.php?msg=219378
Quote from: TotO on 10:24, 22 September 22Quote from: ajcasado on 09:37, 22 September 22The DAC thing is a very nice idea. :o
Hehe. You have liked the idea on September 1st. :)
Here the next post: (require to test the audio mix)
https://www.cpcwiki.eu/forum/index.php?msg=219378
Wow, completely forgotten. At least I'm coherent with myself, not always an easy thing to achieve. :P
I just try the new adapter boards and with a little cap bend, they seem to fit on a CPC 6128:
IMG_20221215_184933_938.jpg
IMG_20221215_184917_839.jpg
If the GPIO is a problem to fit, remove it. (at less from this side)
Quote from: TotO on 20:37, 17 December 22If the GPIO is a problem to fit, remove it. (at less from this side)
I don't think GPIO would be a problem.
Adapter shown in photo, sits on a AY8912 chip, directly soldered on board (i only alligned the 8912 holes to be exactly above the chip), but i suppose that in "real use", there will be a 28pin socket for the 8912 soldered on board, so adapter will plug much higher than shown in photo.
I have a CPC6128 with all chips in sockets, so maybe i will open this one, solder round pins on the adapter and have it plug to see exactly how it looks! ;)
@eto My answer, just because I see it overlap the PPI on the picture.
I just make a more thorough test:
IMG_20221219_194531_910.jpg
IMG_20221219_162808_505.jpg
But now i discover another problem, the back of the keyboard (and possibly a plastic safety clip) hits on the 8910 chip! But i think this can be resolved if, instead of using a 40pin socket, we solder the 8910 directly on the adapter board ;)
Can I put a normal socket into the area of the AY-3-8912? Or is it again one of those ICs where Amstrad decided to make it a bit wider so no normal socket will fit?
I also had a look at my 6128 and compared the available space to a normal DIP socket. Maybe I am missing something but I think if we move the 8910 a bit more towards the keyboard connector, then it would fit perfectly in between the keyboard cable and the capacitors.
see attachment
Quote from: eto on 20:04, 19 December 22Can I put a normal socket into the area of the AY-3-8912? Or is it again one of those ICs where Amstrad decided to make it a bit wider so no normal socket will fit?
Indeed, it seems that all sockets are a bit wider, but if you use sockets with flat pins then you can plug them ok. Sockets with round pins however,are rigid and can't be installed.
Quote from: eto on 20:04, 19 December 22I also had a look at my 6128 and compared the available space to a normal DIP socket. Maybe I am missing something but I think if we move the 8910 a bit more towards the keyboard connector, then it would fit perfectly in between the keyboard cable and the capacitors.
I suppose you mean something like this:
8910_4.jpg
This should free one electrolytic cap from bending.
Quote from: ikonsgr on 20:23, 22 December 22I suppose you mean something like this:
no. more like this.
This one does not have the second I/O port, but that could be added on the right, if required.
Ah, now i see, you move the 40pin socket downwards instead to the left :)
I'll see to it and upload the new gerber files then.
I had to order some PCBs anyway so I measured the available space and designed a PCB. It seems it fits exactly into the free area. The distance between the two rows of the 28pin socket are slightly wider so it should fit into the motherboard without bending the pins. Of course this adapter will then not fit into any other computer but the CPC.
I will try it out as soon as my AY-3-8910A ICs arrive and let you know if it's a fit.
I could test and verify today that it fits into a 6128 without bending a capacitor. It works as expected.
Unlike the version of Iconsgr, this one is without I/O port B and it also will only fit into the CPC range as the socket is slightly wider than in other computers.
Gerber files attached.
Very good for a cheap replacement. There are also the YM2149s available that are compatible (clones) of the AY-3-8910 ... so the market should be really much better then the AY-3-8912s even if the chip is in principle more powerfull.
Absolutely fantastic project.
Sure, the YM2149 is compatible (and even cheaper). I have used it into my X-CPC and ITX-CPC for tests some years ago, but it doesn't sound exactly as the AY.
Ah oh, I was not aware of that.
This indistinguishable sound of the CPC :-)
Don't you need twice the clock speed on the YM to get similar sound output? Afaik the first divider stage on the YM is 32 cycles vs. 16 cycles on the AY.
Quote from: eto on 21:12, 13 January 23Don't you need twice the clock speed on the YM to get similar sound output? Afaik the first divider stage on the YM is 32 cycles vs. 16 cycles on the AY.
It is not related to that. The YM use a 5bit envelope and the sound it not exactly the same for the same note at the same octave.
Should any replacement also guard against ESD from the joystick port? I have just replaced an 8912 on a 664 and they are not cheap, 8910s not much better. Maybe any daughter card can also include ESD protection?
Quote from: Rabs on 20:33, 21 January 23Should any replacement also guard against ESD from the joystick port? I have just replaced an 8912 on a 664 and they are not cheap, 8910s not much better. Maybe any daughter card can also include ESD protection?
It probably makes more sense to make an ESD protection for the Joystick port directly. It then will also protect 8912, not only replacements after the original 8912 has already been destroyed.
Yes! My first CPC got destructed when I touched the screen and joystick port in the same time by accident (that was short after I got it). More than only the chip was destroyed, even the tracks on the PCB jumped up. It needed to be completely replaced.
I checked the different mainboard versions and some of them have capacitors that are connected to each of the joystick port pins. I guess they are there to provide ESD protection.
Would it be an option to just add capacitors to the mainboard, e.g. by using the resistors-array soldering points next to the AY?
Another option could be a small PCB that is soldered to the back of the mainboard. For the C64 there are plenty of PCBs, e.g. this one: https://www.hackup.net/2020/08/esd-protection-for-the-c64-control-ports/
For the CPC of course we would need a slightly different approach as we have to protect 9 pins and don't have GND or VCC on any of the pins. Also SMD soldering is required.
Btw: do we need to protect the IC 74ls145 (pin 8 and 9) also or is that one more robust?
PCB for CPC incl. second I/O port has been delivered and tested.
It fits exactly into the available space of a CPC 6128 without bending capacitors. Due to the space constraints, the second I/O port soldering points did not fit on the right side of the AY. You can see their position on the picture attached.
I have a few spare PCBs here, so if anyone needs one, I can send a PCB for 3€ incl. international shipping as a letter (no tracking). Just send me a PM.
Great piece of hardware! :) :) :)
I know this is an old thread, but I need an economical way to get a AY8912 replacement.
I've purchased a YM294f and will be ordering some of these PCB boards...Thanks for designing them.
Just wanted to ask what are the benefits of adding the resistor array if it is optional?
Thanks
@eto, did you test the adapter on CPC 464?
Also, since i order pcb's for my projects quite often, if there is any interest about such adapter, i could order a small batch and have a cheap alternative for AY replacement ;)
Quote from: namaman on 22:21, 04 April 25Just wanted to ask what are the benefits of adding the resistor array if it is optional?
The "Benefit" is that you ensure 100% that AY chip will work ok, otherwise you might have problems with some versions of AY chip.
Quote from: ikonsgr on 09:12, 05 April 25eto (https://www.cpcwiki.eu/forum/profile/?u=3625), did you test the adapter on CPC 464?
I don't remember if I actually did replace the AY in a 464 or just checked if it should fit.
I know for sure that I replaced it in a 6128.
Quote from: namaman on 22:21, 04 April 25what are the benefits of adding the resistor array if it is optional?
It's not optional. You either need it or you don't need it.
The AY-3-8912 that has been used in the CPC has built-in pull-up resistors on the data lines. If you are using a sound chip with built-in resistors you should not add the resistor array. However the ICs with built-in pull-up resistors are rare and it's much easier to get e.g. a AY-3-8910
A which does not have those resistors built-in. If your sound chip does not have internal pull-up resistors, you should add it. Check the data sheet for your particular IC model.
If this is not done properly it might happen that e.g. keystrokes are recognized incorrectly.
Or that you have a computer with resistor network on PCB and inside the PSG, like on 6128plus...
If the 6128plus has keyboard problems, just get the resistor network out and the problem is solved (details in some other thread around here).
The adapter board has now been published on Github:
https://github.com/etomuc/CPC-AY-3-8910-to-8912-adapter
If there is such a price difference why not make a 10 AY-3-8910 sound card so we can have 33 channels not including lots of white noise.
Hmm, whst if hypothetically a powerful AY many channel card was made but with no cpu digital playback also.
I would better have 2 SIDs than 10 AY chips :)
Having 10 AY-3-8910 chips won't sound 10 times better as having 1. It will still be plain square wave sounds playing.
After 2 chips (to have music + sound effects at the same time), it quikly gets into diminishing returns for each extra AY chip you add.
Quote from: zhulien on 17:26, 07 April 25If there is such a price difference why not make a 10 AY-3-8910 sound card
This is not a sound card. This is meant to fix a CPC whose AY is malfunctioning.
If you are looking for a multi-channel sound card, check out the PlayCity.
Where can I get/order some of these PCBs?
I'm building an Oric-1 replica which uses an AY-3-8912 of which I have none, but I do have several AY-3-8910, so the adapter would come in handy :D
Quote from: robcfg on 18:45, 07 April 25I'm building an Oric-1 replica which uses an AY-3-8912
This particular adapter probably won't work. Amstrad used a slightly wider footprint for the 8912 than usual.
But for normal footprints there are probably already plenty of options out there. Just check Github for projects.
Quote from: Pollo on 17:43, 07 April 25I would better have 2 SIDs than 10 AY chips :)
Having 10 AY-3-8910 chips won't sound 10 times better as having 1. It will still be plain square wave sounds playing.
After 2 chips (to have music + sound effects at the same time), it quikly gets into diminishing returns for each extra AY chip you add.
i agree, but still if the chips are 1/10th the price (plus sockets and labour additions)
Haven't been able to get a definitive answer on wether the YM2149F needs the pull-up resistor array installed for the "datelines".
The Git page says the pull-ups are on the "datalines", should that actually say the IO lines? Is that a mistake?
According to the Datasheet the YM2149F does has pull-ups on the IOA0 to IOA7, and IOB0 to IOB7.
doesn't need
Quote from: namaman on 00:30, 12 April 25The Git page says the pull-ups are on the "datalines", should that actually say the IO lines? Is that a mistake?
Yes, my bad. It now says I/O pins. Thanks for pointing it out.
Quote from: namaman on 00:30, 12 April 25According to the Datasheet the YM2149F does has pull-ups on the IOA0 to IOA7, and IOB0 to IOB7.
Do you have a data sheet that specifically mentions the YM2149F not only the YM2149? I couldn't find one that mentions the F so I am not sure if the YM2149F is the same as a YM2149. For the 8910 vs 8910A the little post fix is the difference between having pull-up and not having pull-up.
As far as I can tell the YM2149F and the YM2149 are the same...just different revisions...of course I'm not 100% sure about that as I also couldn't find a data sheet of the 'F' variant either.
Quote from: Pollo on 17:43, 07 April 25I would better have 2 SIDs than 10 AY chips :)
Having 10 AY-3-8910 chips won't sound 10 times better as having 1. It will still be plain square wave sounds playing.
After 2 chips (to have music + sound effects at the same time), it quikly gets into diminishing returns for each extra AY chip you add.
Bomb Jack arcade has three AY chips; Gyruss arcade uses five, driven by a Z80. That's the most that I know of. Still, no filters.
I had to check:
That sounds really nice indeed.
Edit: well, according to Mame, Gyruss also has one SFX channel. https://github.com/mamedev/historic-mess/blob/master/src/mame/drivers/gyruss.c
The AYs are sounding a little low in that mix compared to the real thing. Also it sounds a bit sparse without the two AYs of sound FX going. Gyruss was usually the noisiest game in the arcade and the bass would resonate all through the cabinet. Stereo speakers too, which was unusual for he time.
I read somewhere that the SID chip was originally meant to have 128 note polyphony - can you imagine - and Bob Yannis was dissatisfied with its ultimate form. Everybody was saying Bob, you're crazy, this chip is already doing way more than anybody asked for. And Bob Yannis decided ok then screw computers, I'll make synths instead.
When we look at the history of sound chips, Yannes was the only guy who cared about computer audio in the early 80s.
It's really appaling to see how the others didn't even try. SID capabilities should have been the norm in that era, not the exception.
I have a theory about it actually.
Yamaha was clinging on their FM synthesis patent and discouraging everyone else. And Yamaha didn't want to put their precious tech on budget computers. That would have overshadowed their keyboards.
I mean, why bother improving sound chips like Yannes when Yamaha can come and dominate whenever they want.
All that lead to that sorry state until the Amiga dynamited everything with sampled audio.
Edit: and the SID was patented too! So another hurdle for competitors...
So the PCB's arrived from JLCPCB today and I promptly built one up...
IT'S ALIVE!!!!!!
So that was a mission...lots of dead parts.
definitely some over voltage or reverse voltage issue.
Just wanted to thank everyone for your support and encouragement.
The only remaining issue is the stupid delete key does not work!!!!!!
Arrrgh...I think I'll ignore it for now...