megadrive sound buzzing [Archive]

megabomberman

10-15-2007, 10:19 AM

Just today from when I turned on my megadrive there is a sharp buzzing coming out which is driving me crazy...

I checked to see was it the games fault but I tried a few more and it was the same.

I changed the cables coming to and from the tv and nothing changed.

I checked was it the tv by using me nomad and its fine.

So the problem has to be with my megadrive....

What do you think is causing this?

I have a feeling it could be the cartridge slot because I had an old faulty pga game that buzzed just like this..

I've blowed into the a/v socket and the cartridge slot and nothing has worked, what should I do,

Thanks...

evildragon

10-15-2007, 10:48 AM

try a different powersupply.

YM2612 buzzes when low on power.

megabomberman

10-15-2007, 11:14 AM

wow cool will try that

megabomberman

10-15-2007, 11:30 AM

Nope sorry didn't work, must be something else? Any ideas?

evildragon

10-15-2007, 11:39 AM

no other idea, sorry.. just try and make sure no ground is shorted or anything like that.. could be a ground loop.

megabomberman

10-15-2007, 11:51 AM

Right I don't think its that, I'll open it up anyway and mess with the jiblets inside there.

evildragon

10-15-2007, 11:57 AM

Yea, if I had to guess any other ideas, I'd put a shot on the caps.

wait, you never mentioned which version of MD you're talking about. I assumed you were talking about MegaDrive 1. not 2..

because the 1 had a more complex op-amp.

megabomberman

10-15-2007, 12:05 PM

No. 2, make a difference, perhaps its just connector pin filth or dirt in the av socket...

evildragon

10-15-2007, 12:09 PM

Possible, especially the ground. But is the video ok? The video and audio share the same ground pin as the ground is common.

For a model 2, I have no clue. My specialty is the model 1's.

megabomberman

10-15-2007, 12:13 PM

The picture is perfect, every peripheral and connection is perfect, every game is perfect the cables are perfect

And it was working fine last night.

The only time I've heard buzzing like this before was with a faulty game. So it leads me to think that its the cartridge slot,

I'll go and try out a load of stuff and see what happens, its very frustrating.

evildragon

10-15-2007, 12:17 PM

You don't happen to have a 32X attached, do you?

Pins B1 and B3 on the cart connector are audio input pins.

(with the system facing you, pin B1 is the bottom left)

megabomberman

10-15-2007, 12:19 PM

nope dude this, is something wrong with my megadrive 2 console only, either dirt or somethings loose, I don't have a clue, but one thing is for sure blowing in doesn't work, i'll give you a shout in a while after I poke around at it, thanks anyway man

Zebbe

10-15-2007, 12:54 PM

I'd open up the whole console, vacuum clean it from dust everywhere and use a topz wherever that power can't get rid of the dirt. Vacuum cleaning has saved my computer twice (last time yesterday actually) and bettered the sound of my Game Gear once.

Joe Redifer

10-15-2007, 03:31 PM

Vacuuming dust is always better than blowing dust... for obvious reasons.

Did you try a different cable? I am too lazy to scroll up and re-read the description of the problem to see if you already tried that, however I am not too lazy to keep typing this continuous sentence which could have ended quite awhile ago. Oh well.

Genesis Knight

10-15-2007, 03:57 PM

Doesn't vacuuming build up a potentially dangerous static charge? That's why they sell compressed air.

evildragon

10-15-2007, 04:11 PM

I always use compressed air.

http://img.photobucket.com/albums/v395/Evilweredragon/latemd12.jpg

That was cleaned via Compressed Air. Would you believe that this Genesis once looked like a pile of crap and had ants LIVING in that?

Genesis Knight

10-15-2007, 05:05 PM

LOL, I remember that one.

Joe Redifer

10-15-2007, 06:34 PM

The thing about vacuuming is that it sucks the dust away forever. Compressed air just moves dust to float around and land again. It can also blow dust into crevices which is not good. A good method might be to blow first and then immediately suck. Either way you should finish it off by wiping.

evildragon

10-15-2007, 06:42 PM

I do the blowjobs on the Genny's outside.

LOL

that way the dust lands well, outside.

megabomberman

10-16-2007, 09:15 AM

I opened it up and it didn't even seem that dusty, everything seemed grand, I had a poke at everything, there wasn't even that much dust to clean.

Now every time I turn on the sega, in between the licencing screen and the sega logo, the sega half stalls for a second lets out a bleep (that sounds like it could be the sound chip failing?) and then instead of sound there is just a buzzing,

Sometimes I can hear a tiny bit of the games sound in the background

To be honest i think it could be hopeless my megadrive could be dead :(

Zebbe

10-16-2007, 10:53 AM

Perfect situation to get a new Mega Drive WITHOUT the cursed license screen.

megadriveworld

10-16-2007, 03:12 PM

Yes, go for for the HD graphics and sound model, you will definitely feel more 'elite'. You'll also be getting slighter cleaner sounding music!

Joe Redifer

10-16-2007, 06:37 PM

Yes, I agree! Get a model 1 without the license screen and you will feel infinitely superior. Just look at me... I own that model and I feel as if I'm better than almost all of you! I highly recommend it!

megabomberman

10-16-2007, 06:51 PM

well guess what, its working perfect again, makes no sense, just happened to work fine when I turned it on there about 20 mins ago, I'm afraid it could start acting up again, but this makes no sense. Oh well, I'll make the most of this either way, thanks anyway lads.

evildragon

10-16-2007, 07:33 PM

Joe Redifer

10-16-2007, 08:11 PM

Siamey

10-16-2007, 08:42 PM

That point about low power is interesting! I had a snes/gen power adapter thing i bought and it had 2 wires coming out of it cause i guess the port is a different size on snes. It let out a buzzing/humming thing when i used it on the gen. Maybe thats what it was :D

Also, hey joe! Love your door into summer mix :) Do you still make tunes? we should collab!

EDIT: Also, I'm new here, so Hi everyone :) Im a huge fan of everything genesis/sega/video games in general.
Ive got about 11 gen1s and 4 gen2s and a couple sega cds 1 and 2, plus some 32xs and a nomad, and im trying to build a list of which work and stuff.
I wanted to make a thread about fixing a segaCD 1 cause i fixed a segacd2 with the fuse thing but im wondering if anyone knows where the fuse is located on the model 1 and how effective that is as a fix. I can't post new threads for some reason :/ do i need to build up my post count first?

Thanks!

evildragon

10-16-2007, 08:58 PM

Good to hear, megabomberman.

evildragon, you only have Genesis stuff. I have Genesis, Master System, SNES, TurboGrafx-16, Neo Geo, Saturn, PS1, PS2, NES, Gamecube, N64, Wii, Xbox, Xbox360, Dreamcast, Virtual Boy, Gameboy Advance, Neo Geo Pocket Color and a DS. I totally PWN j00!!1!!
You obviously don't know the coolness of my arsenal.

Genesis Model 1 Rev 1
Genesis Model 1 Rev 2
Genesis Model 1 Rev 3
Genesis Model 2
Sega CD Model 1
Sega CD Model 2 Rev 1
Sega CD Model 2 Rev 2
Sega 32X
Sega Dreamcast
Xbox
PlayStation
PSone
PStwo
Atari 2600
NES
SNES Model 1 Rev 1 (External APU)
SNES Model 1 Rev 2
Commodore 64
Apple IIgs (Recently Added)
Gameboy
Gameboy Color
Gameboy Advance
PC Engine (with CD)
Nintendo 64

Siamey

10-17-2007, 12:57 AM

How do I tell apart the revisions of my model 1s?
Also whats an external APU? :D

Sorry about asking why I can't make new threads, I guess its obvious I didnt read the rules :D

evildragon

10-17-2007, 01:00 AM

How do I tell apart the revisions of my model 1s?
Also whats an external APU? :D

For determining version:

Revision 1:
(Electrical Aspect)
Main CPU: Signetics
Audio Quality: Excellent
TMSS?: No
EXT Port?: Yes
GLU Chip: 2-Chips
(Physical Aspect)
EXT Port Spot?: Yes
Genesis Logo: 2-Shade Grey
LED Bezel: Ring (Red Plastic Is Part Of It)
Feet: Rubber/Plastic
HD-Graphics?: Yes
Notes: Motherboard Can't Be Overclocked
Mainboard Picture: http://img.photobucket.com/albums/v395/Evilweredragon/sys.jpg

Revision 1.5:
(Electrical Aspect)
Main CPU: Unknown
Audio Quality: Excellent
TMSS?: Yes
EXT Port?: Yes
GLU Chip: 1-Chip
(Physical Aspect)
EXT Port Spot?: Yes
Genesis Logo: Unknown
LED Bezel: Unknown
Feet: Unknown
HD-Graphics?: Yes
Picture: http://img.photobucket.com/albums/v395/Evilweredragon/SEGA6.jpg
(Picture provided by Sashi on the Electronics Forum)

Revision 2:
(Electrical Aspect)
Main CPU: Motorola / Hitachi (More?)
Audio Quality: Good
TMSS?: Yes
EXT Port?: No (Has Solder Pads However)
GLU Chip: 1-Chip
(Physical Aspect)
EXT Port Spot?: Yes
Genesis Logo: Monochrome
LED Bezel: Red Removable Plastic
Feet: Plastic
HD-Graphics?: No
Picture: AWOL (At the Moment, I'm looking for the picture.)

Revision 3:
(Electrical Aspect)
Main CPU: Hitachi (More?)
Audio Quality: Poor
TMSS?: Yes
EXT Port?: No
GLU Chip: All-In-One (Contains YM2612 and VDP)
(Physical Aspect)
EXT Port Spot?: No
Genesis Logo: Monochrome
LED Bezel: Red Removable Plastic
Feet: Plastic
HD-Graphics?: No
Notes: This model is VERY closely related to the Model 2 Genesis.
Mainboard Picture: http://img.photobucket.com/albums/v395/Evilweredragon/latemd12.jpg

Also, for external APU on the SNES. The early version of the SNES (commonly turn yellow), have the APU mounted as an extension on the main motherboard. Later versions (while still retaining shape of the early unit, but remaining grey for the most part), have the APU directly on the motherboard.

Siamey

10-17-2007, 01:42 AM

Whoooa thanks man :D i need to check mine over :D

Why the different audio quality? what was the audio quality of the model 2 (and nomad even) ? could i notice the difference between excellent, good and poor? So much to research :D:D:D

Im totally ripping open all my mine to find a signetics chip, i want the best audio quality !!!

megadriveworld

10-17-2007, 07:10 PM

The model 2 seems to have lesser audio quality, possibly outputting at a lower sample rate. Doesn't sound as clear or smooth.

evildragon

10-17-2007, 08:18 PM

It's the OP Amps it has, very shitty design, one of my friends has a mod for that to get awesome quality (he calls it better than emulator quality), I'll see if I can get him to post here.

Joe Redifer

10-17-2007, 09:10 PM

Pffft. Anything is better than most emulator's quality. My real Genesis sounds better than Fusion, though that one certainly is the closest to the real thing. That one sound sample of this devised "filter" that the guy made over at those other forums was WAAAAAAAAAAAAAAY too bassy. Sounded bad.

evildragon

10-17-2007, 09:19 PM

Actually, I heard his samples, it has NO NOISE at all, he made a big thing about the rewiring of the OP Amp.

Joe Redifer

10-17-2007, 09:29 PM

Are you listening to the same recording of the Knuckles sound test I am (OGG format)? Low noise, yes. Too much bass that wasn't there originally... also yes. Is that a bad thing? Absolutely.

evildragon

10-17-2007, 09:43 PM

Are you listening to the same recording of the Knuckles sound test I am (OGG format)? Low noise, yes. Too much bass that wasn't there originally... also yes. Is that a bad thing? Absolutely.
This guy doesn't even come here. You do realize the Genesis is actually lacking in bass, right? It's op amps aren't responding to that frequency it should be.

Like I said, I'll get him to post here. Otherwise, no statements should be said for something you have no clue over. He knows more than me for the wiring of the Genesis audio system than I do.

Joe Redifer

10-17-2007, 11:11 PM

I know what sounds good and what sounds bad, and the Knuckles sound test (http://www.99-gtp.com/ucm/S3&KQST.ogg) sounds like the bass was cranked up way too high. It sounds very bad. My Genesis already has awesome bass. Streets of Rage stage 6 and 8 can literally shake the room, and my bass/treble, etc are all set flat. Yes, it has very low noise, but I'd take a small amount of noise to have proper-sounding bass.

Siamey

10-18-2007, 11:21 AM

Yea I'd want mine to sound the way the composers assumed it was going to sound when they wrote it. All I know is I can dance to angel island zone 2 off my tv. Drums and bass sound great as-is.

I wish I knew enough to be able to mute different channels of sound from the gen1r1 cause then I could sample every track of a song I like, in the best quality. I did that with a gym plugin for winamp cause I wanted to use the original bassline and square instrument in a remix.. but It would be totally cool to get it direct from the system.

TmEE

10-18-2007, 03:16 PM

The best sound you could get from your MD (any version) is to take your soldering iron and start building Crystal Clear Audio Mod :
http://www.hot.ee/tmeeco/MDSNDMOD.JPG
A pic of it how it looks like in my MD2 :
http://www.hot.ee/tmeeco/SNDMOD.JPG
A sound sample : Vapor Trail Stage Theme (OGG)(1.5MB) (http://www.hot.ee/tmeeco3/VTST.OGG)
If you want more samples, just name the game.

NOT recommended for people unskilled with soldering irons !!! You can SERIOUSLY damage the sound chips in your MD.

One thing : If you have MCD and/or 32X, then they won't make any sound, reason : I myself don't have them and thus can't add them.

evildragon

10-18-2007, 03:30 PM

Ahh, you rewire the entire mixer, thus only Genesis mixing is done..

Siamey

10-18-2007, 11:36 PM

dude can i hear ice cap zone act 1 and angel island zone act 2? that would be awesome. Also is there a book you could recommend for someone like me who has only soldered a new fuse into his segaCD and knows nothing about eclectronics and modding of this depth? I REALLY want to make circuits and crazy shit like this but i dont know where to start, I need a really beginngers book :(

THONKS!:D:D:D

TmEE

10-19-2007, 01:26 AM

Sonic3 tunes arrive this evening (so after 10hours after the time I wrote THIS)

BUT I can't recommend any books, as I myself have 2 books on electronics, and they don't say anything about soldering, and they're all Estonian, and that's a language only a fraction of Earth's population could understand. I have 7 years of experience with soldering iron, so ... only thing I could say is, that take something fried, and start using your iron on it so you could get the feeling of it, and use your fingers, then you know when things get too hot (so if you burn your fingers, you know that you held the iron in place for too long)...

Siamey

10-19-2007, 03:20 AM

can you damage a board if you hold the iron on the contact you are soldering for too long?

TmEE

10-19-2007, 06:42 AM

It depends on a board, some shittier boards (including MD:( ) loosen their tracks after a while, and if that happens, well you're not screwed, but it will still be a headache(as you have to mess with wires then, in relatively tight areas), but you can damage transistors(all semiconductors, and electrolythic caps) by holding the iron too long. Resistors tolerate heat pretty well.
You can make a separate board like one person did, but you should make it small enough to fit into the shell ;)
My method is prefferable for persons who are good at surface mount stuff (which requires good soldering skills)...
One thing : separate flux is ABSOLUTELY necessary... without it you'll have much more trouble.
Seems that it has got little out of topic...
Anyway, after band practice I'll be recording some samples...

EDIT : Samples recorded, but my connection sucks really bad this evening... I hope tomorrow is better (I couldn't upload anything as connection broke up all the time).

TmEE

10-20-2007, 12:36 PM

Samples are here (24hours late...) :
Sonic 3 - Angel Island act 2 (http://www.hot.ee/tmeeco3/S3AA2.OGG)
Sonic 3 - Ice Cap act 1 (http://www.hot.ee/tmeeco3/S3IC1.OGG)

Myrkwood

10-22-2007, 01:12 PM

I noticed my original MegaDrive II had crap sound quality. As in really quite bad. I got a new one and the sound and everything like color were absolutely great but controller port one kept messing around with me. I then got a modified one so I could play it 60hz (I live in the UK damn it, all I need now is 60hz TV) and the sound quality and stuff it pretty good but it sound deteriorated compared to my second one). Damn I have no idea what to do with it but I'm sure I'll get over it unless anyone knows what's making it like that.

Zebbe

10-22-2007, 01:18 PM

Get the first model. It is better.

Myrkwood

10-22-2007, 11:03 PM

Is there any specific thing that might be causing the difference in sound quality between my megadrives though?

TmEE

10-23-2007, 01:29 AM

Older MDs have better sound mixing circuit. The newer model, the worse it gets. In any case, the sound sucks in original form... heh, all my game consoles have audio mods to get these last pieces of superb audio quality that's destroyed in the poor mixing circuits in the systems...

Myrkwood

10-23-2007, 01:17 PM

Problem is... I have no idea how to mod my console :S.

evildragon

10-23-2007, 01:44 PM

Since I can read schematics, if you live in Florida, I could do it for you. It would be on a separate PCB board though.

TmEE

10-23-2007, 01:46 PM

It's not particulary hard, but without soldering skills and some knowleddge on electronics, you'll not get far... I've got 7 to 8 years of experience, I started when I was 10... and I'm not as smart as I look, that audio fix I made for MD is made in a trial and error method, since I know very little about analog electronics (I'm more into digital stuff)... some basic things only...

I even have the PCB layout on the schematic page :
http://www.hot.ee/tmeeco/MDSNDMOD.JPG

evildragon

10-23-2007, 01:56 PM

Yea, I still think a diode should be used on the outputs, to prevent damage. All my electronic devices have diodes on their output stages.

(in my case, on my Palm pilot, it's DAC has a diode on each channel output, so when the buzzer buzzes, it doesn't get shoved into the DAC, or vice versa)

TmEE

10-23-2007, 02:03 PM

Well, try putting a diode on an audio line !!! Audio is AC, and diode makes it DC, and what good sound would come out from a straight line ?

Myrkwood

10-23-2007, 02:55 PM

Damn I live in the UK. Thanks for the offer anyways. I have exactly 0 years electronics experience so that doesn't help :S. I know someone who does though. Maybe he could help me if I gave him the diagram. Would it be simple enough to just give it someone who knows what he's doing?

evildragon

10-23-2007, 03:00 PM

Well, try putting a diode on an audio line !!! Audio is AC, and diode makes it DC, and what good sound would come out from a straight line ?
A diode does NOT make it DC, unless your making a rectifier.

A diode allows current to flow in one direction, and not the other. In audio, it can allow you to drive a speaker, but current can't flow back INTO the audio generating device possibly damaging it.

Notice how some sound cards have a diode on their audio line. They know it very well too.

AC to DC: Rectifier, or diodes setup to BE a rectifier.

EDIT: I stand corrected, I'm confusing diodes and rectifiers.

megadriveworld

10-23-2007, 04:23 PM

What would be good is if somebody with the mod, recorded tracks with and without the audio mod, from two different Genesis of the same revision (or before and after of a same console). To see how much a difference the mod truly makes (Using line-in lead from the Genesis to your computers line-in/analogue mix socket) for clear recording.

evildragon

10-23-2007, 04:28 PM

Joe Redifer

10-23-2007, 06:40 PM

i try to keep my machines in their original condition as much as possible.

LOL. Do you even own a Genesis that hasn't been modified in some way?

TmEE

10-24-2007, 01:15 AM

http://http://arcade.ym2149.com/megadrive/ (http://arcade.ym2149.com/megadrive/)

CCAM definately kicks ass !!!

evildragon

10-24-2007, 01:24 AM

LOL. Do you even own a Genesis that hasn't been modified in some way?
Yes, a model 1, late rev.

megadriveworld

10-24-2007, 03:19 PM

Well the difference I can assure you is better.

Old: Humming sound, clipping (model 2 genesis)
New: Very clear, no noise, no clipping

But recording with and without, somebody better have two genesis then as suggested. i have 4-5 genesis', but im not doing this audio mod, because i try to keep my machines in their original condition as much as possible.

I believe you, just it would be interesting. Infact I think quite some time ago now you did actually post some examples, this is going way back though.

To be honest, with the sound quality I'm getting from an early PAL MegaDrive (HD Graphics logo, no licence screen) there really would be no point in a mod, or point in buying a Genesis 2 I guess. The sound is ever so clear.

That mod I take it makes the overall sound, sound similar to emulators (Fusion anyway, as that's accurate), more chorus with a slightly clearer sound with more treble. I've found having more treble isn't always as good as it happens, if the game originally intended to have a bassier sound, it can sound very weak sounding and you need to adjust the EQ.

Joe Redifer

10-24-2007, 06:30 PM

Yeah, I don't like the emulators that have the increased and cleaned treble. It removes some of the grittiness that makes the Genesis sound so cool. It's like taking a motion picture and removing all of the grain. Doing that also removes some of the life from the image. A lot of my older Hi8 video footage looks much more "alive" than my MiniDV footage which has absolutely no grain (but the camera I use now does). It's an artistic/aesthetic thing vs a technical thing.

megadriveworld

10-24-2007, 06:44 PM

Yeah absolutely. What I've found you can do though, is if you make soundtracks using Fusion, I run the raw WAV recorded tracks through a program that can decrease the treble to a level sounding more 'cloudier' and 'grittier' like an actual Genesis, then saving them as an MP3 for future listening. Once that's done it does sound pretty much identical to the real thing, though what's the point if you have a real unit, line lead and decent sound card..

Joe Redifer

10-24-2007, 07:13 PM

Yeah, I just use my real Genesis which totally PWNZ J00 and everyone else on this board. Makes me feel superior. :)

megadriveworld

10-24-2007, 07:31 PM

Lol! I have an early model too!!

Joe Redifer

10-24-2007, 07:40 PM

Dude, we should, like, totally start a secret society or something!

megadriveworld

10-24-2007, 07:42 PM

Here's an example of the above actually.

From a real Genesis
http://www.fileden.com/files/2007/9/18/1440588/h_nova_10.mp3

From Fusion (With modified decreased treble, closer to the real hardware's sound).
http://www.fileden.com/files/2007/9/18/1440588/Heavy%20Nova%20-%20BGM_10.mp3

As you can see, good final results, though there's still a very slight difference in the EQ, I could probably experiment further to get it even closer. If anything, Fusion is improved sound quality, but there's just something about having the real authentic sound and having a recording of real hardware doing its work.

Same track from Fusion, unmodified
http://www.fileden.com/files/2007/9/18/1440588/heavynova_fusion_noedit.mp3

Notice how Fusion unmodifed sounds low in bass due to the high treble, and overall kind of... far too crisp.

Props to Steve Snake though, the YM2612 emulation itself is spot on. He should probably think about a way of decreasing the treble in future releases, so then the actual EQ will sound closer to the real thing.

Dude, we should, like, totally start a secret society or something!

Oh yeah definitely! Straight away!

Joe Redifer

10-24-2007, 09:45 PM

Good job with that. I could definitely hear a large difference between unmodified Fusion and REAL hardware. Too bad you have to run it through a filter just to get it to sound authentic, though.

TmEE

10-25-2007, 01:18 AM

I really don't like the decreased trebles in original sound of MD, and the very poor stereo... reason I made Crystal Clear Audio Mod... I could use my EQ to get them back, but what would you get back if these are sucked into the poor mixing circuit. No offence, but MD sound sucks badly without CCAM... ESPECIALLY from the headphone jack, the WORST place to get sound (what the hell was Sega thinking of usign such low quality parts in MD !!!)

Joe Redifer

10-25-2007, 01:34 AM

If you say so.

megadriveworld

10-25-2007, 03:08 PM

Lemmings 2 'Outdoor' theme recording straight from a 'HD Graphics' Model 1 via line-in.
http://www.fileden.com/files/2007/9/18/1440588/l2_outdoor.mp3

Lemmings 2 'Shadow' theme.
http://www.fileden.com/files/2007/9/18/1440588/l2_shadow.mp3

Very clear indeed, with the right amount of bass and everything. It's Model 2 default audio that sucks... That mod probably helped but meh.. I'd still rather just have a nice clean early original model. It will also make you feel far superior playing games the way they were originally intended to be played, no cheapo revision model!!

Of course, this isn't to make the Model 2 owners feel bad, it's just ashame about its default audio quality. Sonic and co can still be enjoyed on pretty much any model.

Joe Redifer

10-25-2007, 06:30 PM

this isn't to make the Model 2 owners feel bad
I'm saying what I'm saying to make Model 2 owners feel bad. I want them to be über jealous. Also I want them to make me their king or something and send me money. :D

megadriveworld

10-25-2007, 08:29 PM

Oh I just felt a bit sorry for the Genny 2 owners, here's me telling them they will feel superior playing the original early models (well actually it's true) but I just don't want to make them cry. Of course, they could always look to you as their King and send you money in return for some early Genny 1's perhaps? Or are you the kinda king who says... "IT'S ALL MINE, MUHAHAHA". The ownage King basically.

Joe Redifer

10-26-2007, 12:32 AM

I am the PWNAGE king.

TmEE

10-26-2007, 01:18 AM

My MD2 should make ALL of you über jealous !!!

evildragon

10-26-2007, 01:32 AM

Don't try to impress Joe Redifier. He is unimpressable.

megadriveworld

10-26-2007, 10:18 AM

The modded MD2 is nice I'll give you that.. But... Original Model!

TmEE

10-26-2007, 12:04 PM

Original model sounds better than unmodded MD2, but modded one sounds a lot better... all the 52KHz that YM2612 outputs gets into your ears (if you have some nice HiFi with good speakers)... original model has something like 24KHz or so, and MD2 16 or so when either is unmodded. And yes - YM2612 samples at 52KHz !!!

evildragon

10-26-2007, 12:10 PM

But, if the human hearing range is about 20KHz, why bother?

TmEE

10-26-2007, 12:17 PM

But the higher unheard freqs do tickle your ears, and I really hate the absence of them... if the sound of the original MD1 would be around 24KHz and not as distorted, and with such poor stereo (all for MD2, but in worse form), I'd not have touched my MD2's audio at all... nearly all my consoles have audio mods (even DC which does have some crap in its audio part)

megadriveworld

10-26-2007, 12:21 PM

The mod's interesting, I'd rather have the original audio sound though from the original model, it just doesn't sound right too crisp, too sharp, it doesn't work with game music of this kind.. It kind of goes clangy.

TmEE

10-26-2007, 12:25 PM

Two worlds collide here... you probably like the emulators to be 22KHz setting too (then it sounds more or less like original), I like super sharp, as clean as possible... exact opposite

megadriveworld

10-26-2007, 12:30 PM

Nope, the emulators sound awful at 22KHZ, mainly due to doing this also disables Fusion's 'high quality' mode which counters the emulation problems.

Super sharp with these kind of game tunes just doesn't seem to mix to well, in my opinion anyway, it kind of sounds artificial, fake and not 'real'.

To be honest, even though the real thing probably played around 22khz, I'm listening to some recordings from my model and they do actually sound a bit higher, but not to the point where they are just so sharp there's hardly any bass. Need that bass man..

TmEE

10-26-2007, 12:35 PM

I want to listen some recordings of Sonic games from your MD... I want to do some comparsions with my MD2...

megadriveworld

10-26-2007, 12:48 PM

Sure, I'll post some from Sonic 2 soon.

Joe Redifer

10-26-2007, 06:08 PM

I don't know where you're getting this "poor stereo" from. My Genesis 1 has great stereo separation.

TmEE

10-27-2007, 12:44 PM

Go to Sonic(any) sound test, get silence, and start RINGing... plug out one RCA from your TV(or HiFi or anything else) and you know what I mean.

evildragon

10-27-2007, 01:16 PM

i get 100% stereo seperation on my model 1..

TmEE

10-27-2007, 01:35 PM

don't believe it, ESPECIALLY when it comes from head amp

evildragon

10-27-2007, 01:44 PM

Well don't believe it then, but as you said, you've never messed with an early model 1 before.

TmEE

10-27-2007, 01:49 PM

But it still has Sony head amp, and it is a VERY low quality chip

evildragon

10-27-2007, 02:01 PM

It may be low quality, but the channels are still handled separately. InA, InB, OutA, OutB.

http://cgfm2.emuviews.com/img/mega3.gif

TmEE

10-27-2007, 02:06 PM

So are the opamps in MD2 (and newer MD1s) but still they mix stereo... 10% of one channel in other is WAY too much... my MD2 has now 99.9% separation.

evildragon

10-27-2007, 02:15 PM

The early model 1's however used a much larger and more robust IC. It internally handled each channel alone, there was no mixing, just op-amping..

TmEE

10-27-2007, 02:18 PM

What IC ?

evildragon

10-27-2007, 02:25 PM

What IC ?
On the early model 1's, theres a Sony OpAmp right at the volume POT, that's where the amplification is done. This is a more robust IC than the ones used in later unites. It's a DIP package, can't miss it.

TmEE

10-27-2007, 02:26 PM

That's the chip I'm talking about !!!

evildragon

10-27-2007, 02:32 PM

That's the chip I'm talking about !!!
It's not the same chip though as the later model Genesis. They all have the smaller surface mount revisions, this one is a much larger older version.

Look, I don't care if you don't believe me or not, so lets just drop it.

TmEE

10-27-2007, 02:38 PM

Yes, the DIP16 with Sony CXA 1034(or something like it) printed on it, that's what I'm talking about, and that's the worst thing that Sega planned to put into MD !!! My italian TV-repairman friend examined the chip, and he said it's a very very low quality part... distorts the audio out, and has poor stereo separation.

evildragon

11-13-2007, 07:25 AM

For those who want to hear the model 1 Genesis, here it is: http://blackevilweredragon.spymac.com/sgacxa.ogg

this is from playing a music CD on a model 1 CD on the Genesis via the headphone jack. There is no buzzing sound on real hardware.. my recording equipment isn't grounded right here for some reason.

EDIT: And here is from Sonic 2.

http://blackevilweredragon.spymac.com/gensound.ogg

TmEE

11-13-2007, 10:41 AM

Sonic 2 sounds pretty awful, but the CD is pretty good, but there's still lack of high freqs. Try listening metal... all the cymbals would sound lame...

evildragon

11-13-2007, 10:43 AM

I think the ring sounds on Sonic 2 sounded fairly well.

Either way, the stereo seperation is there, as I told you, the quality of the CXA is good enough for what it does, so, I rest my case.

TmEE

11-13-2007, 10:56 AM

But it eats some high freqs which I want to hear badly especially from metal, and it produces some amount of distortion which I don't tolerate. In any way, I'll CCAM the Genny model 1 that Rob sends me (I hope it arrives soon)... I've heard what MD can do, and I'll not accept the sound it does when it's not modded... first the headamp sound was good, but then I listened the input of the chip which was remarkably better and things went on...

evildragon

11-13-2007, 10:57 AM

The distortion isn't that bad as you make it sound though, it's fairly small. Send me an audio file, and I'll play it back into it.

TmEE

11-15-2007, 11:12 AM

As far as I know, you have no flashcart... I'd only give a ROM file with all stuff required (which wouldn't work in emulators... I know quite a lot tricks to get things unworkable in emulators) for some recording... so if anyone is up to it, tell me so !!!

evildragon

11-15-2007, 11:13 AM

I was talking about OGG files actually. Burn it to CD-R and play through Sega CD, which would go into the Sony CXA chip out the headphone jack.

TmEE

11-15-2007, 11:25 AM

I know... but well.... I'm suspicious... and I care much less about hardware I don't have than what I have (MD alone currently)... if there's anything I want to hear, it'll come out from MD alone... MD CAN do 52KHz sample playback, so pretty clear sound can be achieved (perfect for metal ;) ), but 4MB is not much to deal with (but a minute is more than enough for demonstration)... plus some FM music and PSG form my MSE for MD/Genny.

evildragon

11-15-2007, 11:29 AM

Sega CD sounds on the Genesis sound better than the Genesis' own FM sound. The DAC in the YM2612 on the model 1 Genesis might possibly be of lower quality, thus the CD example the BIOS sounds are low, but when the CD sound kicks in, it's higher..

OR, something between the 2612 and the CXA are of low quality.

I could even video tape this for you too, if you wanted vid proof..

TmEE

11-15-2007, 11:38 AM

all YM2612 implementations are high quality, but something between is the fault... usually some filters...

OK, I'll send you a small clip of something...

evildragon

11-15-2007, 11:51 AM

Yea, possibly the filter, electrolytic perhaps?

The only thing between the CXA and the Sega CD I think are some ferrite beads.

Siamey

11-26-2007, 04:50 PM

Nice! thanks alot for the sonic songs man, Im going to print out the schematics, and try it on at least 3 of my gen2s as soon as I know enough about electronics. :D

Siamey

11-26-2007, 04:52 PM

uhh... it just printed out 7 pages of sammo hung's biography from wikipedia. What the fuck. That's what I get for not checking the buffer before I turn on my printer. Anyways..

philb

03-02-2009, 07:36 AM

Any chance someone could help me diagnose what is wrong with my recently purchased Megadrive 1?

I think its a similar problem to the one that started this thread.

When I put a game in the picture is fine but the sound just is just buzzing, same on multiple games. I purchased a SCART lead for the console and the sound did play briefly for one game but is now back to just the buzzing.

Any help greatly appreciated.

Phil