The SNES Audio hardware research behind chipsynth SFC

Get chipsynth SFC here plogue.com/pro...
Custom electronic test rigs were built and designed by me.
Actual testing and reverse engineering was done me and Hubert Lamontagne and myself at Plogue over a period of years.
01:20 Teardown of console variations
07:37 Digital Capture
10:43 Renders are all different
12:38 MDFourier SPC (beta)
25:40 16kHz on a 32kHz ZoH DAC stairsteps
28:05 Analysis of the reconstruction filter
30:00 Ceramic Resonator and Heat issues
Corrections
-SHVC-SOUND were not the most manufactured version of the SNES. Just happens to be the most common version I locally find In Canada (that's not really a good sample)
-there are no "'GMP" revisions but in fact "GPM" . Dyslexia at work.
More info on MDFourier junkerhq.net/MD...
MDFourier SPC is beta but full sources will be published.
Tracks used:
Mathew Valente - Theme of Despair
Pocaille - Post​-​Quantum Ultra​-​Luxury Doomscrolling
From the official chipsynth SFC launch album
toycompany.ban...
And
Apoplexia - Vega Genesis
From the official chipsynth MD launch album
toycompany.ban...

[@truecuckoo]

I love this!

[@snoopdoggdankkush9285]

I feel like ur gonna make a video on this (:

[@nichttuntun]

Hi Cuckoo, me too :) Awesomeness again.

[@rybateman]

Really hoping this means you'll be making a video - I bought the ChipsynthMD after hearing about it from your channel!

[@Aidan_Lawrence]

Your restraint with not venting on that awful proprietary connector is admirable. It’s the bane of any SNES SHVC tinkerer. Stellar work as always!

[@plgDavid]

Thank you! Yeah that _pesky_ connector. Haha.

[@ChrisLeeW00]

It's the kind of thing Sony + Nintendo would do, and many companies do in an attempt to keep their work from being copied. It worked in the sense that it stalled reverse engineering through it's production lifetime.

[@Vospi]

This stairsteps video bugged me for years, too. :) I was so, so excited to see the update from you!

[@plgDavid]

Its very well made otherwise. I've huge respect for the guy, but, yeah this part.

[@Vospi]

@@plgDavid I teach people how to compose/produce music, and when they hear that 16 bit 44.1 is the only spec you need... well...

[@nichttuntun]

Back again...playing with it for 2 hours now and love this thing. Sounds and feels aesome. FM brings out some killer tones and in general - like the other CS synths, this things has a huge amount of individuality and character-wise awesomeness...unparalleled in plugin-land. Thank you David for doing this. Cheers

[@plgDavid]

Much much love. Thanks!

[@nichttuntun]

@@plgDavid you're welcome :)

[@bf0189]

I love how you explained the nuances of DACs at the end! Thank you I feel like I have a deeper understanding.

[@rwkee]

Always a treat when you publish a new video ! Thank you for all the work you put in your projects and videos ! Very informative and a pleasure to watch.

[@Diggo84]

Man, what perfection! Thank you so much for that, I'm a SNES and MD lover. Its price is fair, I just can't buy it because I live in Brazil, and the dollar here is very expensive. I would love to have that. But I downloaded the demo, I only have 4 minutes, but I could play a little

[@getter7seven]

All these deep dive vids are always good and interesting.

[@Awakia1]

I've been waiting for a good SNES flavoured sampler for YEARS especially one with an intuitive interface. Also, a cheeky "The Lick" at 0:25

[@plgDavid]

The lick: on purpose :)

[@uomodibassamorale]

de licc iz evriwer

[@bprzy852]

David - thank you so much for creating this plugin. It's literally a work of art. I'm incredibly humbled to be able to simply buy this amazing bit accurate emulation after all that painstaking work. I'm beginning work on the soundtrack for an indie game which must sound like familiar SNES music... and this little thing... wow. Wow. Wow. Wow. I've only just started to scratch the surface and it's unbelievable what you guys achieved. I'll be watching TSSF's in-depth videos to try to get my head around everything that's possible.

[@plgDavid]

Its been a bad day, but this makes it all better. Thanks

[@alf3k1]

You are just crazy, this is beyond fanatic!! WOW

[@_boof]

I'm high enough where this makes sense but I know I won't retain any of the knowledge. Definitely buying the plugin though.

[@DCeeMusik]

Dopeness! Oh yeah, the "licc" @ 0:25

[@J0hnSell]

Its an absolute masterpiece, the god of all snes plugins. Thank you guys for putting the unbelievable amount of time into this, and thank you for not releasing it until it was absolutely perfect.

[@ihatemago4807]

thanks again for releasing this dude wasnt expecting it this soon ^^

[@Carlos_Rodrigo]

Nothing else but Superb Work !

[@citrusui]

I love the dedication you and your team went into reversing the SNES sound chip, especially considering its edge cases. I don't expect to see any more work going into reversing the many other lesser-known sample-based engines, but I hope you consider it one day. There's still a big chunk of games that haven't been so much as ripped, unlike Genesis & Super Nintendo (there's about 5 or 6 systems I could list, but no point in begging). For now, I'm just glad that SPC has been mostly "solved". 😃

[@plgDavid]

Always love suggestions, any particular one?

[@citrusui]

plgDavid: If you insist... GBA is one that is very close to my heart. Not many people seem to care or enjoy the sound because the GBA hardware DAC sounds very noisy and 8-bit, but I believe it's got potential to be cleaned-up. There's a tool called "GBAMusRiper" (sic) that can rip a handful of games, but not much work has been done since. Also worth mentioning is the PS2 -- though most games use streamed music, a handful actually use sequences. This one is likely very difficult though, as even fewer rips exist. Games that use sequences on PS2 include Kingdom Hearts, Final Fantasy XI, and Xenosaga Episode II.

[@plgDavid]

@@citrusui GBA is far from fringe. Actually the 'Nearest' interpolation mode of SFC, is a rather crude way to simulate the default GBA SDK driver

[@coen123]

going to Monty's house and making all his dacs zero-order hold so THERE WILL BE STAIR-STEPS. Joke's aside, im glad you brought that up. I'm not an expert on electrical engineering and DA conversion, and watching his video (plus a couple of others) did gave me the idea that the filtering in zero-order hold dacs were more pristine than in reality. Admirably, he did say that he was oversimplifying a bunch of concepts, so i get why it would annoy some people.

[@nichttuntun]

Always a very exciting day when a new Plogue synth is coming out :) Congratulations and thanks for sharing. Cheers PS. Blind buy as always :) Btw, post interesting video although I nearly didn't understand a word :o)

[@ChrisLeeW00]

Amazing work, and I really can't argue with the price of the plogue software, it's cheaper than buying a SNES right now.

[@JACKSONPRYORBENNETT]

Love it!!

[@iridialux]

*would not exist without this software* THANK YOU!

[@bishopwalton3122]

Buying this weekend..been waiting for a proper snes synth.. Used to use super audio cart but will be uaing this..

[@yoshiyukiblade]

As an amateur hobbyist researching to design my own SNES audio driver with a modern DAC, it's great to see experts at work (though most of this stuff is way over my head!). I have a couple questions/comments on the hardware side of things: - At 8:00 you said the audio uses the I2S format, but I believe it's a "right justified" or "standard" format. You can see the data bits aligned to the right side of the LRCK square wave a few seconds later. - Regarding the 3rd order Sallen-Key LPF cutoff frequency (at 29:30), you pointed at the "oscillation frequency," which is 14.5 kHz, but is that the same as the cutoff frequency? I checked the -3 dB point, which is at 11.7 kHz, so I'm not sure which value is correct. On a side note, I've been wondering if the LPF was designed for signals with a 4x oversampling digital filter. The UPD6376 does no oversampling. One of the application circuits in the datasheet shows a 4x oversampling IC (SM5807) preceding it, but no such chip exists on the SNES. An oversampling digital filter eases the filtering requirements by pushing the images out to higher frequencies. At 4fs (128 kHz), the SNES LPF attenuation is -60 dB, so I wonder if they had oversampling in mind when designing it. The DAC used for later SNES revisions use the UPD6379 chip, which has built-in 4x oversampling. Any thoughts on this theory?

[@plgDavid]

Right/left justified is configurable with a pin on some I2S DACs afaik. The Cutoff matches our recordings and spectrum analysis. and did they have oversampling in mind? Beats me but I doubt it. This thing was already quite HIFI for a console?

[@pumbabeats420]

I love this. I love you. I love you all. Never been so excited for an vst in my entire life 💕

[@Irongrip62]

Why did they choose a ceramic resonator? Price at scale.

[@Drfresh1402]

I would prepay for your next 2 developments if the option was available.

[@plgDavid]

You wouldn’t believe just how much this means.

[@justingoers]

@@plgDavid I would do the same! Porta FM and MP are some of my favorite synths. And now this! Yes!

[@Drfresh1402]

@@plgDavid I've already purchased SFC.

[@0e0]

big respect. your attention to detail is sooooo satisfying

[@TotallyGoodatGames]

Wow this is very in-depth!

[@acreil]

I'm glad I'm not the only one who was irritated by the "no stair-steps" thing, or at least the way it's often interpreted. It's completely fine within the context of what the original video is discussing (modern, high quality recording and reproduction of digital audio), but a lot of people seem to watch that video and idiotically assume that it applies universally to all forms of digital audio, digital synthesis and processing, etc. There are lots of "stair-steps" in old music gear, sound chips, etc. that are frequently plainly audible (bit crushers, the PPG Wave, Ensoniq Mirage, the NES triangle wave, Casio keyboards, etc.). That's a large part of why that stuff is interesting. Also, forget the ceramic resonator. The real crime is running audio through LM324 op amps (29:05). The crossover distortion in those is so bad that it's plainly visible on an oscilloscope.

[@plgDavid]

acreil hey! Means a lot I recognize your user name from GS. Whenever I read your posts, I’m like yes, yes yes!

[@acreil]

@@plgDavid Thanks, but I'd really rather not post there anymore.

[@plgDavid]

@@acreil I barely did. Smelled toxicity.

[@acreil]

@@plgDavid yeah, exactly

[@cmd_f5]

Incredible work as always. I need to buy this soon. 🍻⚡️

[@asdf_]

interesting, i have a kawai X30 keyboard that uses the same dac as the snes (NEC UPD6376CX), didn't think it would be so straightforward to capture the digital audio signals .. without all the boot sequence stuff of course

[@plgDavid]

Sounds easy enough

[@goatsoup]

just curious, i have a kawai x130, does that have the same DAC as well?

[@WARDISWARD]

07:57 Ohh fuck yeah zelda 3 ..so many fond memories of that game . takes me back to 1993

[@EnzoCapun]

Could you guys consider an update with soundfont compatibility? Its kinda unhandy to convert them into wav all the time, i know theres sforzando but i think chipsynth sfc has the synthesizing and sample editing tools i needed

[@plgDavid]

Not a silly idea. Wouldnt be that hard

[@warpforge]

I'm curious if replacing the clock source could cause the audio module to produce more useful output for digital capture.

[@plgDavid]

Doesn't change anything for me as the decoding logic syncs on whatever main clock I receive. It would however fix some SPDIF problems for people just wanting digital out compatible with their AVs. There are discussions about that in the MDFourier circles.

[@erdemmemisyazici3950]

26:33 This answers a very old question for me where I wondered why anybody would convert digital to analog. Analog to digital loses information as it is quantified. Digital to analog still has the same number of bits. Answer as it turns out is just so it would play on what you need it to play on. I've heard people say it sounds better, couldn't understand why it would.

[@rezmelon]

SOUND CHIPS, LOVELY SOUND CHIPS ❤️

[@OmoiSenpai]

Whoa. I love this info ^_^ Thanks! Actually, I am working on a video right now, and I am using the SNES's RCA as the input to my interface haha. Well, I did, but now I'm just procrastinating at the moment T_T''

[@palmenros]

Really loved this, I am considering buying it just for the insights it has given me on the SNES. Is the PDF at the start of the video explaining the SNES audio available? Would really like to take a look at it ;)

[@plgDavid]

erm which pdf?

[@palmenros]

@@plgDavid The one showed for example at 3:50 explaining the architecture of the sound system. Thanks, I really appreciate your help!

[@plgDavid]

@@palmenros Ah that! archive.org/details/SNESDevManual

[@jamesho8215]

Very Professional, Great job

[@uhlectronic]

great project!!

[@ianmathews]

Do you know how MisterFPGA 'emulation' line up on MDfourier? This was a great overview, thank you.

[@plgDavid]

Yes. the Mister devs ran the MDFourier SNES test and passed it with flying colors.

[@vybore9494]

Super informative. 👍🏼

[@kitesplash2019]

bless up

[@JoshWhelchel]

Wonderful stuff

[@jtn191]

Did you guys use MD Fourier in the tests for the MD Chipsynth? Nice work!

[@plgDavid]

Post releases yes. That's why many impulses are named (OLD), they didn't match well enough in MDFourier for my tastes and We've redone them!

[@AppliedCryogenics]

Does anybody know of a source of that weird staggered APU connector besides paying $30 for a broken SNES? I've had the SPC700 in my parts bin for a couple years now. I'd hate to modify it.

[@plgDavid]

Not that I know of. Dead SNES cpus and ppus make canibalizing a bit less atrocious sadly

[@CRTWorlds]

Thanks for explaining this so clearly! Look forward to your next videos! I subscribed!

[@ElecDashTronDotOrg]

Awesome video mate

[@mluna]

Amazing video

[@pumodi]

YESSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS

[@FoxerTails]

I'm no specialist in electronics but what would happen if you desolder the ceramic resonator in the SNES and replace it with a crystal oscillator? Better filtering for audio output or would the difference be too minor?

[@plgDavid]

Some have indeed done this, but there are reports of it actually creating issues for some games that were badly designed and assumed >= 32040Hz!

[@visker81]

@@plgDavid meaning we shouldnt touch it as there is no upgrade without issues?

[@johneygd]

Did you have ever tested the bit resolution of each sample,??? I only hear terms like 32khz,16khz or 8khz,but nobody ever talked about the bit rate output of the snes,so why am curious about this, Thanks alot.

[@plgDavid]

16bit stereo mix out, but each sample is compressed using BRR compression.

[@johneygd]

@@plgDavid wow THX alot,but can you also determine the bit depth of each sample or can you only adjust the amount of kilo hertz??? Again thx alot🙏😁

[@plgDavid]

@@johneygd bit depth of each sample is fixed but the encoding is not linear. Read on Sony BRR compression

[@johneygd]

@@plgDavid well the only thing i understand is that BRR samples are encoded into 4bit adpcm format wich the snes interpolates back to 16bit resolution in accordance to the dots pattern in the sample in wich it fills in with lines,then the amount of khz can be determined to be 8,16,22 or 32khz, then a lowpass filter helps cuzz off certain frequency’s just in case to get rid off the remaining potential noise(eventrough the snes does contain a noise generator for winds ,rain or cracky wood effects.

[@Elrinth]

How is this versus Super Audio Cart ? I totally missed this vsti was released. I'll need to go grab it.

[@justingoers]

I think Super Audio Cart uses sounds sampled _from_ an SNES where this is the actual SNES samples but played back through a bit accurate emulator.

[@threemonic]

Hell ya

[@Zet237yt]

This was super informative, thank you for the video. Definitely going to buy the plougue-in very, very soon. Not even thinking twice. :) 25:39 - I *think* the point Monty was trying to bring across here was that the digitally reproduced sine wave didn't suddenly become all jagged and, well, stairsteppy as that seems to be the misconception of some audiophiles regarding digital audio. As Monty's video continues talking about square waves a bit later (at 17:38), the square wave you showed still is perfectly in line of what he does explain, including the expected Gibbs effect. At least I do not see a contradiction between the video you are referencing and your observations but perhaps I'm not looking closely enough! Still, I find this very fascinating to see and raises so many questions in my mind - what happens when you lower the frequency gradually down, away from nyquist, what does the oscilloscope show?

[@plgDavid]

That Monty vid is great. Its just that I think ZoH DACs are more prevalent in the wild (and in peoples heads) than he seem to claim. So in short, some critics are justified. Of course stair steps are not inherent to digital audio.

[@WARDISWARD]

Good stuff

[@The_Mister_E]

...So when do you think you'll use MDfourier analysis on chipsynthMD? 😏 (EDIT: I read an earlier inquiry, never mind~!) I'm just pulling your chain. It's good to see that your consistency tests are working so well! A real gathering of the minds between you two!

[@plgDavid]

We actually did for post 1.0 MD releases! (I replied to this for someone else). thats why there are "(Old)" impulses in the list, they didnt fully match

[@The_Mister_E]

@@plgDavid Speaking of chipsynthMD, is it just me or are the operator LFO toggles missing in the update that just came out? EDIT: Well they once were.

[@JPRacer77Qc]

Méchante job de fou! ;) Congratulations! Wish I was that smart! :)

[@plgDavid]

I'm not that smart. Juste extrêmement obsédé.

[@bodoelsel]

Amazing video even if I didn’t understood everything 😀

[@Polyh3dron]

This is finally out? Buying ASAP. Famicom next PLEASE

[@expertmax32]

Tout simplement genial.

[@htcones99]

That chip can used separately to make some sounds effects?

[@plgDavid]

Typically one of the 8 channels was reserved for sound effects. yes

[@rob0nemusic369]

Bonsoir, je viens tout juste de tomber sur votre plug-in et ça a l'air vraiment excellent, notamment au niveau de la qualité de l'émulation. Néanmoins je me pose des questions au niveau de la légalité étant donné qu'il s'agit d'un logiciel qui émule le comportement d'une carte son. Pourriez vous m'éclairer sur ce sujet ?

[@plgDavid]

Résumer le droit international dans une réponse c’est plutot impossible.

[@plgDavid]

Emuler le hardware est tout à fait légal

[@rob0nemusic369]

@@plgDavid Ok, merci ! J'avais des doutes là dessus. Je vais tester la demo demain et je vous redirais ça 👍

[@rob0nemusic369]

@@plgDavid Je viens de tester la demo du logiciel, et je dois avouer que l'émulation est assez bluffante. Je vais me prendre le logiciel, néanmoins je trouve la période d'essai un peu courte

[@rob0nemusic369]

@@plgDavid Y a t il un moyen d'exporter en WAV avec le SPC player ? J'ai fait un projet sur SNES GSS et exporté en .SPC

[@eformance]

Any idea why Nintendo tented all the vias?

[@plgDavid]

To make my life miserable.

[@johneygd]

You know what would be a really awesome project? If you will come up with a costum chip wich would be able to realtime convert CD audio down into a spc format at 16bit 32khz at 128kbps stream it trough the snes soundchip, now that would be awesome!!!!

[@plgDavid]

It kind of exists in two ways: to sound like any input audio sounds like streamed to the SNES we have chipcrusher. If you want to do it on hardware there exist a new custom Mapper chip that streams audio through the SNES out (not through the S-DSP but still)

[@EnzoCapun]

you deserve my money

[@plgDavid]

Good morning and thanks for making my day

[@EnzoCapun]

@@plgDavid i love so much music and games from this era, its just astonishing how such a perfect piece of work was put together and being able to see the process on it?? Its amazing what you and your team created! Thanks for the plugin, the attention to this community and providing us the walkthrough your process, amazing job!

[@adelyoutube7530]

Keep up 👍

[@bigboomer1013]

Is it possible to make music to sound like donkey kong country music? I just love the sounds that David wise had produced for his music.

[@plgDavid]

To a good extent yes. There are some presets like this, but they quickly use all the sample slots

[@emilalmberg1096]

I note your irritation over pico, nano and micro. Is it the case that people in the US use 0.00 .... micro, instead of pico and nano? As a child of the SI system, I have no problems with prefixes.

[@plgDavid]

I'm not sure. I learned what I know about electronics a bit everywhere, so I just have charts and online converters.

[@erisd8452]

Any plans for iOS versions of your software?

[@plgDavid]

If you are willing to pay the same price as the Mac version :)

[@erisd8452]

plgDavid Sure thing! Just bought the PC version today

[@Kjetil_MB]

Will there be a demo? :D

[@plgDavid]

Yes eventually. No dates yet.

[@mirabilis]

Is MiSTer accurate, I wonder?

[@plgDavid]

YX yes! Didn’t have space to put it in the video but it’s basically perfect now for SNES audio

[@mirabilis]

@@plgDavid Wow! That's great! Thank you for telling me.

[@FaultyTwo]

Ceramic resonator? Oh god.. please no.. Anything but that!

[@BoxingDayAC]

You should point out that human hearing above 15kHz is nowhere near as sensitive as the lower band of audible range. Instead you punish for being inaccurate at 16-20 kHz. FM radio and KZbin don't even bother to modulate audio above 15 kHz. You're wrong, cutoff frequency is 11.55 kHz. 14.45 kHz is the complex part of the conjugate poles. Relying on MDFourier + online calcs, I hope you know how to measure THD+Noise, channel separation, dynamic range and phase distortion. Don't disregard tech specs of aged LM324 either.

[@yeoldmedic7572]

W double o w

[@counivers]

Oh lala Super Nintendo!