Removing the audio distortion on early model Mega Drives (and keeping it tidy!)

Any Mega Drive owner worth their salt knows that the later models have crap audio. However, the REALLY early models, despite having the clearest audio of the bunch suffer from distortion on loud sounds. I've got a VA1 model and I can confirm this! Slightly later models don't have this distortion problem, however the trade-off is for slightly muffled audio. If only there was a way to have both!

I was reading online that the distortion on these early model Mega Drives is actually the fault of the headphone assembly. And since you need to plug in your audio cable to the headphone jack to get stereo, you can see where the problem lies. I found THIS GUIDE that claims you can fix the distortion by soldering a headphone jack directly to the Mega Drive's amp, which skips over the headphone assembly and thus solves the problem. I tried it out and it works! However, in terms of tidiness, you either need to have a headphone cable dangling out the back or drill a hole into the case to mount a jack. Not a fan of either of these options.

So I was thinking. Why not use the headphone jack that's already there instead? So that's what I did!


BAM! The clear audio of a launch model Mega Drive without the distortion! And with no modifications to the appearance of the console!

Basically, all I did was solder the wires from the Sony chip directly to the console's headphone jack instead of a headphone extension cable.



I did need to work out what pad is what on the headphone jack, but checking the internet told me that the on the mainboard side of things (where the wires going from the headphone jack connect to the mainboard), pin 1 is ground, pin 2 is right and pin 3 is left, so it was just a matter of using a multimeter to check which pin matches up with what solder point on the headphone jack.

This does require you to de-solder the wires going from the mainboard to the headphone jack, though, otherwise you'd still be getting the distorted audio. The connector may look like a plug, but it's actually soldered in place.


There you are, a real simple mod that gives you the clearest audio you'll ever hear from the Mega Drive! And you don't need to mess with the appearance of the console either!

 

Weird is, if SEGA could connect the headphone plug directly to the Sony chip, why bother to make that headphone assembly?

 

Because the level without the headphone amplifier is way too low to directly drive headphones, and almost too low to even directly drive the amplifier in a TV...

 

And this is why people do the crystal clear audio mod / Helder's MEGA AMP instead of just soldering direct to the chip.

Do you use a Sega CD or a 32X? I haven't looked at this all that closely, but I have a gut feeling that you bypassed the audio in mix, and therefore audio from a SCD or 32X would be absent from the headphone jack.

 

Hmmm, it's just as loud as it was before for me.

I don't, but I figure since all the audio is coming from the body as normal, surely the MCD would have no problems mixing this with it's CD audio? Talking about the model 1, which needs to be plugged into the model 1 Mega Drive's headphone jack anyway.

 

This is what i tried to do my VA2 US launch model Genesis. It had an ear rape on the headphone jack and when not on Headphones with the TV, I get very low audio and this is why i tried recap my VA2 using caps from a VA6 Genesis.