Genesis Glitches

In 2015 I had bought a Sega Genesis off of a friend at the time. I had never actually owned before up until that point, only emulated genesis games / played compilations on other consoles, so I was fairly excited. When I got home and hooked it up I found that there was a really odd issue with this particular console.

I'm not sure if it was the console, or the weird multi-console power adapter I had for it, but when playing games it would produce these really strange audio glitches. This didn't seem to affect the gameplay or the graphics of the games, just the audio.

I did end up recording some gameplay to show my friends, and now, for you as well. I'll be real these recordings are fucking PROFOUNDLY terrible quality. I didn't have any sort of capture cards at the time so I opted to use my crappy webcam (a marginal upgrade from my PS2 eyetoy lmao) pointed at my flatscreen TV since that was a bit clearer than pointing it at my CRT. On top of that the webcam kept auto-adjusting which was incredibly irritating, so I apologize.

But as I said earlier the footage isnt really that important, only the audio seemed to be glitching. I trimmed the footage down quite a bit to just show you the interesting parts I captured, a good amount of times the audio would just completely cut out after that strange record scratch sound, then the BGM and SFX were just completely silent which is hilarious honestly.

Out of all the games I tried, I think Sonic the Hedgehog 2 had the most interesting glitches.

At times it would warp, partially play parts of, or completely mute the BGM. This was also interspersed with this strange 'record scratch' sound. Various sound effects would get pitched up or down, get stretched, delayed, or get stuck and become a drawn out tone. Quickly doing the spin dash would cause the sound effect to glitch more and more the faster and longer you did it.

And of course, occasionally the game would just straight up crash.

It's a little bit upsetting that I didn't get to record all the glitches I witnessed, but I did for most. There was a couple weird variations of the music I didn't get to capture.

The next one I tried out was Golden Axe off of this multi-cart. It wasn't really as interesting as Sonic 2, it just lacked SFX and the drums and bass parts of the BGM would come and go, it then crashed. Immediately afterwards I tried Sonic 1 on the same cart but had no glitches whatsoever. You also see a couple audio glitches from the multi-cart main menu.

The last game I tried was ofc, bubsy. The glitches produced were either high pitched tones or awful garbled chip noise which somehow, someway, made playing Bubsy and even worse. There were also dogs outside howling bloody murder which just compounded the experience. Even just quickly editing this video together gave me a headache.

What could possibly go wrong?

So I did eventually have this guy take this Genesis back, although now I kinda wish I had been able to test more games on it. I didn't have too many Genesis games at the time and a good few of them I tried didn't express any glitches at all.

So later, in 2018, I had at some point picked up an old YAMAHA PSS-480 from a thrift store. This is an old budget 'toy' synthesizer from the late 80's, but surprisingly gives you a lot of control over the FM sound chip inside, as well as having MIDI in and out which was nice because playing on the tiny little keys on this thing was a pain in the ass. Upon researching more about it, I found that the FM chip inside of it (YM3420B) was sort of like a really paired down decedent of the sound-chip inside of the YAMAHA DX7 (YM2128), which I had already knew that the sound chip inside of the SEGA Genesis was like a gimped version of the DX7's chip. It further dawned on me that this keyboard was a bit like a cousin to the SEGA Genesis when playing around with it.

Not only did it sound a lot like the Genesis (playing Sonic BGM MIDIs on it was also very authentic sounding), but I found that adjusting the feedback and modulation levels (as well as the transposing the available keys really high or really low to accentuate it), it would produce really glitchy FM sounds just like this gorked SEGA Genesis that I had in the past!

I've recently recored a few examples here for you so you can see what I mean.

PSS-480 EXAMPLES

example1.mp3

example2.mp3

example3.mp3

example4.mp3

Also, heres a video from the time of the PSS-480 playing CBoyardee's 'killers' midi, just for funzies

A year later from that (2019), I had found another one of these cheapy YAMAHA keyboards at a second hand store, this time it was the YAMAHA 380

Side by side with the PSS-480 they are very similar, but the 380 has a lot less controls and by consequence a lot less control over the sound. It also doesn't have MIDI which kinda suxx. It's still sounds great though, and can produce a lot of the same sound that the 480 can, although I find that the 380's sound is a lot brighter. I have some old recorded examples for you here as well.

PSS-380 EXAMPLES

prettychimes.wav

touchedthewrongtile.wav

bubbob.wav (this ones recorded in dogshit quality,

I'm sorry. It's still pretty in it's own odd way)

So with all this experimentation in mind, I think the general conclusion I've come to is that that crappy 3rd party power adapter for the SEGA Genesis wasn't supplying adequate power for the FM chip inside, and this was causing the chip to miscalculate or miss or the beginning or ending marks for sound envelopes, then causing all these strange glitchy sounds.

I believe I remember that old friend using a different power adapter on that genesis and not having these issues, so this is my best guess. I'm not an expert on FM synthesis though (yet)

Here are a couple links if you would like to read a bit more / check out the manuals on the PSS-480 and PSS-380

PSS-480: www.vintagesynth.com/yamaha/portasound-PSS-480

PSS-380: soundprogramming.net/keyboards/yamaha/yamaha-pss-380/