Sound quality of Genesis games when using Sega CD audio out

[WCP]

So, I know there is a bit of a debate out there, about which Genesis system has the best sound output. I don't know all the details about it, but I think there is a certain early Genesis model, that has a certain audio chip that people tend to say offers the best sound for the Sega Genesis. The Model 1 Genesis unit that says "High Definition Graphics" on the top of the console is the right model, although apparently there are certain versions of that Model that don't have the good audio chip, and certain versions that do.


Anyways, what I really wanted to ask is, if you have your Genesis hooked up to a Sega CD, and you're using the red and white audio out plugs of the Sega CD to go to your stereo, does it matter which version of the Genesis you're using ? What I mean is, if you have that certain Model 1 Genesis that supposedly has the right sound chip, and you're playing Sonic the Hedgehog on cartridge, and using the Sega CD audio out, will you notice a difference in sound quality ?

I currently have a Genesis 2, connected to a Sega CD 2, along with a 32X hooked into it. I'm pretty happy with the setup, but if I can really get appreciably better sound from a Model 1 Genesis, and hook it up to that Sega CD 2, even though it will look a bit fugly, I'd probably go that route, because having the best possible audio would be kinda preferred.

I was just curious if using the Sega CD audio output makes the whole point moot. I'm guessing it would in regards to Sega CD games, but with the carts I'm not sure.

[Darkwing]

I can't really answer your question about the Sega CD audio, but I do know that the very first Genesis model is the one with the best sound, along with being able to play overseas and unlicensed games. It has this FCC number on the bottom:

[Aussie2B]

Don't all model 1 Genesis systems have the same sized slot? Because isn't that physical difference the only thing preventing NTSC Mega Drive games from playing on other US models of the Genesis? I'm a little foggy on this since I've yet to buy any Mega Drive games myself, but I think you're set in terms of imports with any model 1.

[Gameguy]

Don't all model 1 Genesis systems have the same sized slot? Because isn't that physical difference the only thing preventing NTSC Mega Drive games from playing on other US models of the Genesis? I'm a little foggy on this since I've yet to buy any Mega Drive games myself, but I think you're set in terms of imports with any model 1.
They all use the same sized slot. Some of the later games used regional lockout which prevents them from running on systems from another region, most don't have any regional lockout and will work fine besides the physical shape not fitting in.

The early systems don't have a lockout chip which allows them to play all unlicensed games, some games won't work on later systems. This doesn't affect regional lockouts, I used to think it did but it doesn't. You'll still have the same problems with imports even with early model 1 systems. There aren't many problems though.

[stardust4ever]

EDIT: GameGuy beat me to the punch while I was composing my "wall of text" explanation. Read on for the full Monty:

Not quite. Dremeling or cutting the square Genesis tabs like you do on the SNES will allow Japanese Mega Drive games to physically fit, and most earlier games will work. The Genesis region settings is stored in the console BIOS; however they can be changed by jumping/cutting certain traces within the console. This allows DIY modeers to add DIP switches enabling changing the region on the fly, allowing any region locked games to play. Most good Genesis SOAC clones, if they're import friendly, will have a manual region switch built in to allow for this. There are three regions commonly in use, Jap, PAL, and NTSC. There is also a 50/60Hz flag in the GPU as well which is separate from the region flag. It is entirely possible to set a 50Hz NTSC or a 60Hz PAL Mega Drive. Thus there is a 50/60Hz switch mod that has become popular with European Megadrive enthusiasts. Back on topic, games can access these region/refresh settings. If a system is either the wrong region or refresh rate, the game can refuse to load by displaying an error screen, however unlike Nintendo games, region lock is not compulsory so it is at the publisher's discretion whether or not to allow their games to run in other regions. As a result, many games will run just fine on any Genesis or Megadrive. A few titles actually share a common ROM between the US/PAL/Jap regions, presumably to keep costs low since it's cheaper to manufature one ROM chip as opposed to two. These particular games have both English and Japanese texts within their code, and selection of text or graphics displayed within the game are determined region settings of the console itself. All official Genesis consoles have a region identifier, however there was an additional measure added to all but the earliest Genesis BIOS, to prevent unauthorised code from running. This is independant of the region code. This additional code within the BIOS verifies the integrity of the ROM and if the integrity check passes, it displays the "licensed by Sega" message. This message is displayed prior to loading the game and is not part of the game code itself. Unlicensed and pirate game developers quicky discovered a way to defeat the integrity check. I don't know how it works, but some unlicensed or bootleg titles pass the integrity check, while others bypass it. For those games that pass, the "licensed by Sega" message is displayed, typically followed by a second message stating the game is not licensed or endorsed by Sega, and to ignore any prior messages stating otherwise. For those unlicensed games that bypass the integrity check, the "licensed by Sega" screen is skipped entirely. Most later unlicensed games employed the latter strategy. Due to the way the integrity check worked, there was no way to create an updated BIOS to prevent unlicensed games from running while still allowing licensed games to operate. Either way there really weren't that many unlicensed games for either 16-bit console, and most that exist are quite rare. Genesis security is easily be bypassed through code while SNES employed "lock on" technology to utilize the lockout chip from an official game cart.

[theclaw]

Basically Genesis launched with little security. Original systems didn't block unlicensed games as already said.
While region settings sat idle until non-Japanese consoles appeared, they were taken from Master System for backwards compatibility and future use.

Back on topic Genesis audio is already processed before sending to Sega CD. Any differences from there have nothing to do with the Genesis.

[Nz17]

Well those were some pretty good, technical answers! And that just shows that this thread belongs over in the Technical forum, so shuffle-shuffle over there it goes.

/me moves thread to "Technical and Restoration Society" sub-forum.

[BricatSegaFan]

So does this address his question about sound quality on the Sega CD 2? I'm interested as well.

[stardust4ever]

So does this address his question about sound quality on the Sega CD 2? I'm interested as well.Here's a rather lengthy read:
http://www.sega-16.com/forum/showthread.php?7796-GUIDE-Telling-apart-good-Genesis-1s-and-Genesis-2s-from-bad-ones

Sega sure does love tampering with their hardware, LOL!

Well, it seems that while the Genesis saw three release models, Sega revised the danged motherboard, especially the audio/video hardware, at least a dozen times. Genesis Model 1 (especially the earlier "high definition graphics" models) are preferable and generally have superior audio through the headphone jack, but I opened my Genny and apparently mine is the dreaded VA-7 revision (late release Model 1) with the grungy sounding audio. Seriously, the mono output through the AV or RF sounds like it's been passed through an overdrive guitar effects pedal. The audio from the 1/8 minijack is still quite clean though but it makes me wonder if I'm missing something by not having gotten the coveted "high definition grahics" version.

According to the artcle certain Model 2 hardware revisions have downright inaccurate sound levels, especially with Master System games. Oh well, even if the stock sound on my SA-7 Model 1 is distorted, at least it's "accurate" and I can still get a clean line out from the headphone jack set to volume 5.

[BricatSegaFan]

So where would an X'Eye fit into all this

[WCP]

I've read previously about the "High Definition Graphics" version of the Genesis having the best sound (supposedly), but my particular question isn't really about that. My question is, if you use a Sega CD 2's red and white audio out, are you bypassing the entire argument, because you aren't actually using the normal sound output from the Genesis ?

Or, is it a case where the Sega CD doesn't matter. If you use one of the crappy sounding Genesis versions with a Sega CD, and you're playing a cartridge, you're going to get the crappy sound regardless ? I'm just trying to find out if the Sega CD has any bearing whatsoever on the sound quality that you get when playing cartridge games ? I always assumed that when I used the audio out from the Sega CD, I would get cleaner sound overall, but that could be just wishful thinking on my part.

[Gameguy]

To use a Model 1 Genesis with a Sega CD you can use the mixing cable for better results. Plus, the sound quality would depend on the types of games you're playing. Sega Genesis audio would be processed by the Genesis, and Sega CD audio would be processed by the Sega CD. Without using the mixing cable the sound is all processed through the Genesis. With Model 1 Genesis systems you'll only get stereo sound through the headphone jack, meaning you'll have to use the mixing cable if you want to do what you're suggesting with the Sega CD audio output. With Model 2 Genesis systems, the mixing happens through the expansion port so you don't need to use a mixing cable. Either way, this improves the sound quality with CD audio by not having it processed through the Genesis. Genesis audio is still processed with the Genesis either way, so the quality of the sound chips still matters.

[theclaw]

So where would an X'Eye fit into all this

Not the best or worst. Doesn't have separate Genesis and Sega CD outputs, mixing is internal.

[BlastProcessing402]

The SegaCD just passes through the sound generated by the Genesis, either through the mixing cable for a model 1 or through some internal connections for a model 2. If cart games sound good on a particular Genesis, they will sound good with that Genesis connected to a Sega CD. If cart games sound bad on a particular Genesis, they will sound bad with that Genesis connected to a Sega CD.

[BricatSegaFan]

Well hooked up one of my VA6 and the cart sounds was world's better than the X'eye.

[stardust4ever]

Well hooked up one of my VA6 and the cart sounds was world's better than the X'eye.Lucky you. I picked up my Genny from my local used game store in 2011. I got the Model 1 cuz everyone said those were the best and I like their styling. Got a VA7 with the "grungy" AV out, but at least the headphone output is clean. :p

[BricatSegaFan]

Lucky you. I picked up my Genny from my local used game store in 2011. I got the Model 1 cuz everyone said those were the best and I like their styling. Got a VA7 with the "grungy" AV out, but at least the headphone output is clean. :p

Until this thread I've always thought all model 1's were just superior. Next on my list is to get RGB via Scart out of this or maybe s-video