Jump to content
IGNORED

What is the future of sound chips?


karri

Recommended Posts

It appears that Yamaha and other instrument manufacturers create instruments with waveforms recorded from real analog instruments. So the current POKEY + Yamaha are at end of life.

 

This probably means that in the future everybody is using some kind of digital synth for producing sound.

 

I wonder what features would be needed? My personal feeling is that 3 square waves and noise would be the minimum.

 

The goal could be to have a simple thing that could be emulated with a PWM timer or a few timers. Any ideas of a good chip?

Link to comment
Share on other sites

I'm not sure why the Yamaha or POKEY would be considered end-of-life unless you are just thinking feature-wise. The Yamaha FM chips and HOKEY chips have us mostly covered for the future.

 

If you are simply looking at capabilities, then something like the BUP chip with an ARM-based processor that could emulate any type of synthesis with an almost unlimited channel count would be an option. Even to the extent that the microcontroller/microprocessor added in the cartridge could have its own RAM and full stereo compressed audio tracks could be run into the 7800's audio lines. The 7800 could literally have an equal or better soundtrack than a modern Playstation or XBOX.

 

With some sort of Raspberry Pi solution, the developers could program their own synthesis emulation and run virtual analog, sample based, wavetable based, or any other number of methods. And these could be used in combination.

 

Heck, someone could hit the Behringer supply-chain and buy a big lot of the V3397 chips and build a Prophet-5 synth into their cartridge for a minimal additional cost added to the cartridge.

 

We are spoiled for choice these days with tech costing so little and with so many hardware devs out there doing this for the love of the retro scene.

 

I think that, for me, if the sound tech gets too far from the capabilities of the original era then it starts to lose its charm and simply becomes a tech demo. Like Jeff Goldblum said in "Jurassic Park": "Your scientists were so preoccupied with whether or not they could, they didn’t stop to think if they should." 🤣

  • Like 1
Link to comment
Share on other sites

15 hours ago, saxmeister said:

I'm not sure why the Yamaha or POKEY would be considered end-of-life unless you are just thinking feature-wise. The Yamaha FM chips and HOKEY chips have us mostly covered for the future.

HOKEY is a fpga I believe. And Yamaha does not produce FM chips anymore afaik.

Link to comment
Share on other sites

I know this is in the Atari 7800 section, but I just wanted to say that this could apply to Atari 2600 carts too, as some primitive POKEY-like chips were featured in some carts iirc.
However, I'm not sure how a digital synth chip would work on any Atari console tbh, but I would love to hear Pitfall 2 be compatible with 2600+ soon.

Edited by r_chase
missing words.
Link to comment
Share on other sites

Well. I have been trying different instruments on the Furnace Tracker that you can use for making chip music. Some of the chips produce really nice vibrant sound and some ones are pretty awful.

 

So my point is: if you really have to emulate your sound chip anyway why not choose a nice chip? The best chip would be something that has a small number of registers. It should also be easy to control the envelope and the frequency of the sound. And the sound channels should be independent from each other. They should also maintain their pitch in both PAL and NTSC.

 

The practical limitation is probably that HOKEY and Yamaha FM is emulated by the 2600+ ProSystem. So that may be the reason why we stay at HOKEY and Yamaha FM. Actually the best thing might be to use both chips in a game. Could these chips be easily emulated by some cheap microcontroller? Like my Pico in the Otaku project?

 

  • Like 1
Link to comment
Share on other sites

Thanks for the link. This chip is from 2011. I wonder if this is old stock? I tried to check Mouser, Digi-Key, Farnell plus some smaller chip vendors and I could not find any active FM chips. Even if there is some old stock available the cost may be high compared to an emulated solution.

Link to comment
Share on other sites

52 minutes ago, karri said:

Thanks for the link. This chip is from 2011. I wonder if this is old stock? I tried to check Mouser, Digi-Key, Farnell plus some smaller chip vendors and I could not find any active FM chips. Even if there is some old stock available the cost may be high compared to an emulated solution.

I believe the future may be FPGA or some thing akin.  The versatility alone is superb.

On 2/2/2024 at 3:17 PM, karri said:

My personal feeling is that 3 square waves and noise would be the minimum.

So, POKEY comparable then?

 

Four audio channels with separate frequency, noise and voice level controls. The square audio can be clear or distorted.  Added bonus as it pertains to the 7800, both TIA audio channels can be leveraged for noise as well.  Commando demonstrates this beautifully as does Bentley Bear's Crystal Quest.

 

A dedicated POKEY substitution solution like HOKEY only drives the cost of an additional ~$5 per cart.   HOKEY has already been used successfully for several games sold in the AtariAge store, including recent "last chance" POKEY titles and currently being sold POKEY games.

 

The documentation put together by @Synthpopalooza highlights how much typically untapped usage and potential there is with POKEY as well, especially with the distortion settings.

 

Quote

Distortion 10 (AUDCx=$A0 - $AF) ... square wave, pure tones.

Distortion 2 (AUDCX=$20 - $2F) ... triangle wave, bell tones.

Distortion 12a (AUDCx=$C0 - $CF) ... sawtooth wave, buzzy tones

Distortion 12b (AUDCx=$c0 - $CF) ... sawtooth wave, non-buzzy tones...

...& more.

  • Like 1
  • Thanks 1
Link to comment
Share on other sites

26 minutes ago, Trebor said:

So, POKEY comparable then?

Perhaps. So far the Furnace Tracker Pokey demos are not convincing. The SN7 chips square wave instruments just sound better. But it may be that nobody has published good demo tunes for Pokey on Furnace Tracker yet.

 

If the Hokey will emulate both square waves, noise and FM sounds for a decent price then that sounds like a good enough solution.

Link to comment
Share on other sites

Yamaha still produces a sound chip that combines the features of an FM synth and DSP for audio processing.

https://device.yamaha.com/en/lsi/products/sound_generator/

 

YMF827B (APL-5) - 8 channnel PCM/ADPCM sound LSI with DSP for audio characteristic correction
- Audio LSI for automotive,consumer, industrial applications
- up to 8 channnel simulataneous playback of PCM/ADPCM
- Audio Data either transferred by CPU to YMF827(APL5) or stored in Flash ROM locally connected to YMF827(APL5)
- SPI for Host interface (as a master) and memory interfafe (as a slave)
- up to 48KHz of sampling rate
- Pitch change and smooth volume supported
- 2 independent analog output (DAC integragted) and digital output (I2S)
- DSP integrated for audio characteristic correction
- Single 3.3V power supply
- SQFP48
- Operational temperature of -40 to 105℃

 

Or, there is also the YM825 (SD-1) - FM sequencer with 3-band EQ built in
- FM sound source with 16 voices
- Sound quality correction through built-in 3-band EQ
- Built-in speaker with power rating up to 900 mW (5V, RL=8Ω)
- SSOP24
- Operational temperature of -20 to 85℃

 

The second option may be cheaper since it doesn't have the same complexity and it does fit with the retro FM synthesis - albeit with 16 channels!

 

I personally have a soft spot for the AY-3-8910 chips and there are plentiful numbers of clones of this chip:  Winbond still produces a 100% compatible clone today called the WF19054. They are challenging to program for simply because of the state based architecture. But great sounds can be produced, especially when the chips are doubled, tripled, and quadrupled. The sound can get very thick in layers. Just look at the Tron arcade machines.

 

I also agree with the SN7 chips. They do sound great and tend to be better in tune overall. The pure square waves create a specific sound.

 

I would also lean toward a SID or an enhanced SID. I like this ARM2SID + FM FPGA because it emulates two SID chips for stereo and adds Yamaha FM emulation along with it. Imagine the possibilities.

 

Yes, FPGA does seem to be the way moving forward simple because it's cheaper to code an FPGA to emulate the hardware than it is to run a chip fab of technology that old. FPGA also gives us the opportunity to create dream chips that fix bugs in older chips, extend the same chips we love with more features, team up multiple architectures into one chip, or create a chip that has never been seen before. I would love for someone to figure out the schematics for the AMY chip and the GUMBY chip so that we could create a virtual one in FPGA. So many possibilities.

  • Thanks 1
Link to comment
Share on other sites

56 minutes ago, saxmeister said:

I would love for someone to figure out the schematics for the AMY chip and the GUMBY chip so that we could create a virtual one in FPGA. So many possibilities.

Don't forget about the Minnie chip.  Prototypes were produced and heard throughout the halls of the GCC offices.   The capabilities were very impressive for its time (1983).  The kicker, it would have cost less than $2.00 per cartridge to add-on the chip.

  • Like 1
Link to comment
Share on other sites

6 hours ago, saxmeister said:

Yes, FPGA does seem to be the way moving forward simple because it's cheaper to code an FPGA to emulate the hardware than it is to run a chip fab of technology that old. FPGA also gives us the opportunity to create dream chips that fix bugs in older chips, extend the same chips we love with more features, team up multiple architectures into one chip, or create a chip that has never been seen before. I would love for someone to figure out the schematics for the AMY chip and the GUMBY chip so that we could create a virtual one in FPGA. So many possibilities.

Thank you for this info! I really like the idea about a dream chip in fpga. For Wizzy I already have a Furnace Tracker driver that makes a separate stream for every register. @Eagle did a demo like this. Then you runlength encode the streams and use huffman for compressing it. The driver then uses huffmunch for reading the next register value during te interrupt. The nice thing is that the driver and the music goes in the 16k RAM bank that is active during VBL. And the other 16k RAM bank is active during display for Maria tiles. This leaves the entire ROM free for the game!

 

If someone is interested in my Furnace Tracker driver for the SN7 I can share it. It is still a mess but it works.

 

I know that the latest SN2 cart may have the audio driver in the fpga as well. But then we start getting into the area where most of the processing is done in the cart and not in the console. I would like to maintain compability with flash carts and 2600+.

  • Like 1
Link to comment
Share on other sites

I assume that a single POKEY and Yamaha 2151 could be a pretty nice target as I have a Dragonfly with these chips. So at least I can compose tunes using Furnace Tracker and run them on the real hardware. But I need to modify my drivers to use these chips instead of sn7.

 

My guess is that ProSystem emulator would emulate a Yamaha 2151 and a single POKEY on the new 2600+ machine too.

 

So it would be up to 12 channels for the music. If the space is tight I assume that you could just use 6 channels and still get very good quality music.

Screenshotfrom2024-02-0512-57-10.thumb.png.93456268ce08502f2c7149a9107aab5d.png

I just rendered a modified arcade tune in Furnace Tracker. Here it is played only on Yamaha 2151. But I assume that by adding some POKEY percussions it would be just great!

 

  • Like 1
Link to comment
Share on other sites

On 2/4/2024 at 10:02 AM, Trebor said:

I believe the future may be FPGA or some thing akin.  The versatility alone is superb.

So, POKEY comparable then?

 

Four audio channels with separate frequency, noise and voice level controls. The square audio can be clear or distorted.  Added bonus as it pertains to the 7800, both TIA audio channels can be leveraged for noise as well.  Commando demonstrates this beautifully as does Bentley Bear's Crystal Quest.

 

A dedicated POKEY substitution solution like HOKEY only drives the cost of an additional ~$5 per cart.   HOKEY has already been used successfully for several games sold in the AtariAge store, including recent "last chance" POKEY titles and currently being sold POKEY games.

 

The documentation put together by @Synthpopalooza highlights how much typically untapped usage and potential there is with POKEY as well, especially with the distortion settings.

 

The issue with HOKEY is of course, emulation of these features.  Currently, E.X.O. (which uses two tone mode and other nonstandard settings) does not work on HOKEY as far as I know.  If this can ever get sorted, we may have a true alternative. 

Link to comment
Share on other sites

1 minute ago, Synthpopalooza said:

The issue with HOKEY is of course, emulation of these features.  Currently, E.X.O. (which uses two tone mode and other nonstandard settings) does not work on HOKEY as far as I know.  If this can ever get sorted, we may have a true alternative. 

HOKEY works with E.X.O.

Quote
  • 15 POKEY Tunes for your audio enjoyment using built-in HOKEY chip.

 

  • Like 2
  • Thanks 1
Link to comment
Share on other sites

I would love to have dual or quadruple AY-3-8910 chips with controllable filters and a pair of PCM channels. The SN76489 is great, but the AY series just seems to have much stronger bass, and adding a controllable filter would allow full synth sounds that would rival the SID. The PCM channels could be used for basic audio samples such as drums.

 

Or, if I could cram my retro music devices into one cart!

 

unnamed.thumb.jpg.13ac6185ddcae526c4a97111b4c0f830.jpg

  • Like 1
Link to comment
Share on other sites

On 2/5/2024 at 1:32 AM, Trebor said:

Don't forget about the Minnie chip.  Prototypes were produced and heard throughout the halls of the GCC offices.   The capabilities were very impressive for its time (1983).  The kicker, it would have cost less than $2.00 per cartridge to add-on the chip.

Wow, never knew about Minnie, that would have been very cool.. Very interesting food for thought, and a lovely little design..

  • Like 2
Link to comment
Share on other sites

  • 1 month later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...