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View Full Version : does the early JPN MegaDrive have stereo?



AG Wolf
02-04-2010, 06:06 PM
I found a couple different japanese MD machines online and they were shown with stereo composite a/v cables (red, white, yellow leads)... I'm in the states, and I was pretty certain all of our Model 1 Genesis systems had mono sound output from the rear port... but I know the machine went through a couple hardware changes before it even reached american shores... Should I interpret the pictures I've seen as some kind of confirmation that the early models produced stereo sound aside from the headphone jack?

according to this thread:
http://www.sega-16.com/forum/showthread.php?t=10047
specifically, the first response by "Ace"
the earliest model is the one with the little ® symbol next to the sega logo on the corner of the machine, so I guess I should be looking out for that one? Neither of the two I found on ebay have that but they're still shown with a stereo a/v cable

TmEE
02-04-2010, 06:50 PM
the VA1 JP MD1 I got here has regular AV out aka only mono from there

Christuserloeser
02-04-2010, 06:54 PM
They all got stereo via headphone out.

AG Wolf
02-04-2010, 07:00 PM
Thanks tiido... damnit, there's really not going to be any easy way for me to get decent stereo sound until I find a good model 2, is there? lol

Christuserloeser
02-04-2010, 07:04 PM
What? No! The model 1 does output stereo.

- A model 2 however is an option if you let Tiido do a CCAM, which will fix the horrible sound of any model 2.

ApolloBoy
02-04-2010, 07:18 PM
Those stereo AV cables are probably ones that came with the PC Engine Duo and Core Grafx.

AG Wolf
02-04-2010, 07:36 PM
What? No! The model 1 does output stereo.

- A model 2 however is an option if you let Tiido do a CCAM, which will fix the horrible sound of any model 2.

I'm aware the model 1 outputs stereo via the headphone jack, I was just curious if the earliest model happened to actually have stereo output from the r ear jack.

I have tiido's CCAM sitting beside me, waiting for a Model 2 with the sony video encoder chip because I can't pull S-video off the cheap samsung model without unnecessary extra effort. The only Model 2 I own also has very bad VDP interference as well as the samsung video chip, so I'm not even bothering with it.

Until then, all I have to work with are 7+ model 1 machines, only two of which have "good" audio circuitry, and a genesis 3 with the mono motherboard... I had entertained the idea of building a second channel amp circuit for the Genesis 3 (I have both a quad op-amp lm324 chip and lm386n sitting here) but I don't have the time/attention span required when I have college work to focus on as well.

@apolloboy: ah yes I forgot they used the same plug.

kool kitty89
02-05-2010, 02:17 AM
I think the only thing about soem early model 1s (not sure about JP, but definitely some early US models as came up in a recent discussion) don'y mix mono properly, and instead onyl output one of the L/R stereo channels from A/V (don't recall for RF), so you won't even get prober mono sound. (this came in a thread asking why most MD games lacked a stereo/mono options opposed to SNES games and such)

Of course, using stereo via headphones aviods that issue as well.

Iron Lizard
02-05-2010, 02:57 AM
What is hard about getting stereo out of the headphone jack?

Silanda
02-05-2010, 08:07 AM
What is hard about getting stereo out of the headphone jack?

Nothing really, a 3.5mm jack to phono leads will do it. That said, it's not ideal as the headphone amp in the model 1 is pretty crap and can be noisy (on mine it distorts if set to higher volumes, not necessarily a problem with cart games but it has to be set fairly high to get a good mix with the Mega-CD's sound).

kool kitty89
02-05-2010, 06:07 PM
Nothing really, a 3.5mm jack to phono leads will do it. That said, it's not ideal as the headphone amp in the model 1 is pretty crap and can be noisy (on mine it distorts if set to higher volumes, not necessarily a problem with cart games but it has to be set fairly high to get a good mix with the Mega-CD's sound).

That sounds liek the amp is going bad, or you got a super cheap amp in your console, more likely the latter. (hiss is normal, but not distortion)

The mono amp can go bad as well, usually a matter of aging capacitors.

AG Wolf
02-05-2010, 06:21 PM
The headphone jack gives some nasty hiss, and I get the slightest 60hz hum on it as well... the hum may be some other grounding issue elsewhere in my computer/tv/etc setup, but the hiss is still a nuisance.

Silanda
02-05-2010, 07:43 PM
That sounds liek the amp is going bad, or you got a super cheap amp in your console, more likely the latter. (hiss is normal, but not distortion)

The mono amp can go bad as well, usually a matter of aging capacitors.

I'd go for the super cheap amp theory. It could be the caps decaying, but it has done it for at least the last couple of years (probably forever, but it was in storage for a long time so I'm not sure). It's not universal distortion, some sounds are affected badly while others aren't at all. Oddly it doesn't seem as bad with my new speaker/amp setup as it did with my old, which is strange as it is definitely the volume of the headphone out and not the speakers that causes the trouble. Now my Saturn on the other hand, that is bad for hissing, really bad.

TmEE
02-05-2010, 09:12 PM
The amp used in MD is meant for walkman type cassette players.... chip noise will be drowned out by the cassette noise... but in MD you got no noise and chip noise is clearly heard.....

kool kitty89
02-06-2010, 05:59 AM
The amp used in MD is meant for walkman type cassette players.... chip noise will be drowned out by the cassette noise... but in MD you got no noise and chip noise is clearly heard.....

I only notice a modest hiss on my VA3s and VA5/6 model 1, mostly at low volume levels. (one of th eVA3s also has popping/crackling sounds at low volume levels as well, not sure if that's a problem with the slider or the amp going bad -not sure why the latter would only affect low volume -only below ~50% volume)