Audio buzz on Megadrive/Genesis 2

[Retro Access]

Hello.

I sell cables on eBay and I know a lot of people here buy my cables, sometimes with issues with various hardware. I'm trying to iron things out with the various converters, upscalers etc but not everything works with every device. We started selling sync based cables because of issues with some hardware and composite video, but that created a new set of problems with some peoples equipment. I do stick to the recommendations for correct capacitors etc to be used by the video ICs in each console but that doesn't always help. I'll probably be posting more, but what I'm posting about today is something that happened recently that made me terribly depressed and frustrated and caused me to have to take a break from selling.

I asked this person to post here so people would back me up, but he never did, he just left negative instead which is probably going to lose me some sales.

Basically he had an LG SCART TV and bought the standard composite based Megadrive 2 cable. It didn't work, and caused the same issue as happens with Samsung TVs, ie. it doesn't like the Megadrive composite signal for sync, but only in 60Hz. He has a modded Megadrive 2.

So I told him to buy the composite sync version (which we call raw sync, it's to prevent buyers getting confused with the mention of composite.) He did. Next I know he is complaining of audio buzz which "never happened before" and did not happen with his previous cable. Not sure how true this is given his previous cable did not work on his TV. Anyway he said he tried it on a Sony CRT too so there we go.

But then he sent another mail saying he now got audio buzz on his composite based SCART cable too, and saying that the sync cable must have busted his console. I am maintaining that it cannot have busted his console. All the cables are properly grounded at audio and video points, and fully shielded with the shielding connected to the metal parts at both ends. Nevertheless I too get audio buzz on some screens on my Genesis 2 no matter what, and I maintain this must be due to some issue with the console and it's lower quality audio and possibly on top of this, some sort of ground loop or interference within the console itself. It does not happen with the first revision of Megadrive 1 which everyone is likely aware has excellent audio, and I wire those cables for that system in exactly the same way. He was demanding that I fix his Megadrive, wanted to send it to me all the way from Europe (I'm in USA) so I basically told him I could not do this. Can anyone here back me up? I could have understood maybe if I had somehow accidentally miswired this cable, however it was obvious I did not because he was still getting audio on both channels and a perfect picture. Plus we tested it on my equipment and it definitely did not break my console in any way.

I now have negative feedback saying the cable broke his console.

I'm pretty put out by this because I know I did not break his console, and I know eBay won't do squat to help and that feedback is going to be on my record for a year. I actually told him to post wherever he could on techie forums asking if this sort of buzz could wreck his actual console but of course he has not done that.

[Endymion]

Consider yourself backed. There is no way your cable, from what you have described, could have physically caused damage to his system.

I admire you for the work you do, seriously, but it's because of lunatics like that person that I do not perform mods for other people. He has no clue and is helpless to do something for himself, but as soon as he doesn't have the results he wants he's become the expert on everything about the problem and its solution.

[mrsmiley381]

He's using a Genesis 2, which universally across its revisions had audio problems. Furthermore, it's old hardware that probably needs a cap replacement. Unless you somehow managed to wire a cable in an incredibly wrong way, sending power or something to pins that should not have power, I highly doubt you're responsible for his Genesis 2 flipping out.

Did he even say what games he used to test it? If he switched games, that's not even good science for determining audio issues.

[Retro Access]

Well I right away told him it could be a cap problem which may have manifested recently, which I somewhat regret because he then thought I would offer a repair of his console.

I would do more research into fixing Genesis 2 sound issues but I haven't bothered because the obvious solution is to just buy a first revision Genesis 1. Just wondered though if anyone had a little insight into the true cause of this audio buzz? Obviously there is the inferior sound chip, beyond that though the buzz on certain screens suggests poorly thought out circuitry. It's not the first person to blame my cables for it.

This has really caused a lot of stress because having feedback on your account saying you broke somebody's console is definitely going to make some people look elsewhere.

[Retro Access]

Well, my account is wrecked.

http://feedback.ebay.com/ws/eBayISAPI.d ... egative_30

Horribly depressed.

The thing is, I do not claim to be infallible. If I somehow short circuited a system by not adding heatshrink to +5V and a loose strand of wire touched ground? Yes I could accept that. If I wired the wrong wires up to somehow damage the sound, if I connected +5V to audio (the pins being right next to each other in the SCART) yes I could accept that. Do I think it's likely? No, and I've never done it before. But I can't accept this - I tested that cable on my Genesis 2. I test every cable on my own console so it's be my own console to die if I messed up. My Genesis 2 is working fine. Plus, even if you think the cable could have somehow got damaged in transit - he has audio still working, just with a buzz. He sent me a picture of the SCART, it looks fine. I mean sure if he said it'd shorted completely (when he said it was broken, first thing I asked him was whether he had a power light) then I'd have accepted blame. Heck I'd have accepted blame if it shorted cause it got wet in the post, I definitely don't waterproof packages after all. But I'm completely blameless, so I don't deserve this and that's what's making me heavily depressed and completely sick of eBay.

I am simply wrecking my sanity over this and I expect I'm probably going to have to start a new account. This is literally the worst feedback I could ever have got - people might think you could get worse but it literally does not get worse than this because eBay would remove anything libellous even if it was true. You could get feedback like "seller put dog crap in this package" and it'd get removed as libellous even if you literally put crap in the package. So yes, for me it literally does not get any worse than somebody stating my cable broke their console and as I have competitors it absolutely will lose me sales. We are scraping by on super low income at present and I do not need this sort of disaster.

I don't think he's a nutcase either. It's entirely likely his Megadrive or something else attached to it developed a fault, capacitor related or otherwise in the time between testing the cable that didn't work and using the new one. I mean sure, he doesn't believe me. I could be lying. If it was possible to break the sound like this, and I was a dishonest seller I'd be saying "No sorry, not possible" right now. That's why I asked him to post here.

We see faults all the time. The other day I had a line of interference running up the screen when I tested the cables. If i was a customer I could well have said "Well you broke my console, it now does this on all of them." But yep, it did it on all of them and I knew the first cable I plugged in wouldn't have damaged the console and caused it, so I blamed some external thing - we were running all the consoles that day and two computers and a CRT. It's really easy though for customers to see this sort of thing and blame you though which is why the feedback system on eBay really, really sucks. They already have 100% buyer protection so god knows why they need to be able to paste misinformed stuff all over your account that sticks there for a year and costs you sales.

[Zapf]

It still shows you as a top rated seller, so I think wrecked might be a little harsh. I literally never look past that if its on a sellers auction page, I don't know how others might be about that though.

[Endymion]

Actually, this is what any potential buyer will see. 13 newer feedback testimonals and over 99.9% positive feedback for more than ten years. This is honestly a lot more important than a 100% record, and when you get with the snooty, otaku-loving, console collecting type who are going to hoard crap from their childhood by way of their rose-coloured lenses like it all deserves a holy shrine, this lot are way less likely to trust someone who sets up shop tomorrow. Don't let one collector who doesn't have a basic high school understanding of physics and is literally frightened of learning something take you down a peg for your knowledge. As it stands, knowledge is the only thing that will get this person's Genesis 2 fixed.

If they prefer the blame-game to learning something and fishing for themselves for a lifetime, they're the one to suffer for it.

[trunk]

As others have stated please do not get discouraged by this. You have thousands of positive feedback. I personally purchase a few cables from you and they work great. I know the person doesn't appear to want to check up on this but you might also want to point him to the Tech aid section on the sega-16 forums where TmEE and such reside. They have all sorts of console version comparisons for audio as well as crystal clear audio mods for MD/GEN 2 models. Like you I'm going to guess that the caps are going bad in the console as it is so common for 90's electronics.

I'd like to think that people that get into actual retro consoles(and RGB) would want to make an effort to look into these things otherwise they should just play on emulators(because they wouldn't be that picky anyway).

[viletim]

I would do more research into fixing Genesis 2 sound issues but I haven't bothered because the obvious solution is to just buy a first revision Genesis 1. Just wondered though if anyone had a little insight into the true cause of this audio buzz? Obviously there is the inferior sound chip, beyond that though the buzz on certain screens suggests poorly thought out circuitry. It's not the first person to blame my cables for it.

Make a cable, exactly as you normally would, but do not connect any video related signals. Essentially, make a Genesis 2 audio cable. Plug in one of you usual SCART cables and play some games till you find one that buzzes. Swap over the SCART cable for the audio only one. Does it still buzz?

If doesn't buzz without the video signals then your cables are at fault. That is something you can easily fix.

[RGB32E]

http://www.retrogamecave.com/ac-adapter-central.html

You're welcome.

If doesn't buzz without the video signals then your cables are at fault. That is something you can easily fix.

Good point! Though the AC adapter performance seems to be a contributing factor for audio quality in general.

Edit:

A good read - http://www.pcenginefx.com/forums/index. ... 9#msg99669

The info is out there if you look for it!

[Retro Access]

I would do more research into fixing Genesis 2 sound issues but I haven't bothered because the obvious solution is to just buy a first revision Genesis 1. Just wondered though if anyone had a little insight into the true cause of this audio buzz? Obviously there is the inferior sound chip, beyond that though the buzz on certain screens suggests poorly thought out circuitry. It's not the first person to blame my cables for it.

Make a cable, exactly as you normally would, but do not connect any video related signals. Essentially, make a Genesis 2 audio cable. Plug in one of you usual SCART cables and play some games till you find one that buzzes. Swap over the SCART cable for the audio only one. Does it still buzz?

If doesn't buzz without the video signals then your cables are at fault. That is something you can easily fix.

With all respect, and I see this posted a lot on forums by people who are respected in the field of RGB mods, that cables bought on ebay can be a problem (this causes me problems, you can imagine) but how exactly do you easily fix something that is wired 100% correctly with full grounding at both ends?

Whenever somebody reports audio buzz I request that they check the plug and make sure the grounding points are all fully connecting, including most importantly - shielding wires at the SCART end as they are in most danger of coming loose.

Beyond that, as long as the cable is fully shielded with grounding points for audio and video and connected at the metal points for DIN and SCART I honestly cannot see how the buzz would be down to the cable.

Yes, I also get audio buzz from the Genesis 2 with the standard Sega AV cable. It's very mild, and it's also obvious because it only occurs on the copyright screen*, but overall the sound from this system is tinny and crappy as is a few later Genesis 1s I have. Only the first gen model I own has appreciably better audio.

But most importantly, can you say that the following would possibly be the case? I am saying definitely not.

You have a Genesis 2. It has no audio issues, or very quiet audio issues (as many do.)
You have a SCART cable. You use it, it's working with audio fine.
You buy another SCART cable. It's properly grounded and shielded. You plug it into the system, and your buzzing issue is suddenly amplified. The audio channels still both work, and the picture is fine but you hear this louder buzzing with this cable.
You plug in the older SCART cable. The Genesis 2 continues to have the audio issue.
The fault is clearly the second SCART, which damaged your Genesis 2 beyond repair.

I am saying this cannot be the case. I do not dispute that the events occurred, only the conclusion made by the buyer. You should also factor in the existence of another Genesis 2, which SCART cable number 2 was tested on, which remains to not be damaged in any way.

Thoughts?

*It might well be occurring elsewhere, but I can't hear it. Not a lot of people know this, but I am somewhat nervy about the whole audio problem issue, as I am about 70% deaf.

[Retro Access]

http://www.retrogamecave.com/ac-adapter-central.html

You're welcome.

If doesn't buzz without the video signals then your cables are at fault. That is something you can easily fix.

Good point! Though the AC adapter performance seems to be a contributing factor for audio quality in general.

Edit:

A good read - http://www.pcenginefx.com/forums/index. ... 9#msg99669

The info is out there if you look for it!

I am also aware of the AC adaptor issue.

Any one of multiple things could have occurred to cause this buyer's problem, and I don't believe any of them to be permanent.

Nonetheless I would be very reluctant to accept to undertake a repair of a console (with eBay feedback riding on it) without knowing EXACTLY what the cause was. Because even if I swapped out the caps and the issue was in his own home, he'd hardly be satisfied as it would not have gone away. Even if I sent him a replacement Genesis 2 from the USA, he may well have had the same issue with that one. And I don't know what he *personally* defines as bad audio buzz anyway. To me, low level buzz is tolerable. To others, certainly not. Though I'm not entirely sure why this particular buyer is insistant on using Megadrive 2s.

It's just a potential minefield and would very likely have resulted in negative feedback either way, I just felt I went the shortest and cheapest route to getting my account tagged with a black mark.

[viletim]

Beyond that, as long as the cable is fully shielded with grounding points for audio and video and connected at the metal points for DIN and SCART I honestly cannot see how the buzz would be down to the cable.

It's all very well to say that you have a thick shield ground conductor, but what does it actually measure? The only important property of the ground connection is the resistance. It should be less than 0.3 ohms from one connector to another. You can measure it with a multimeter if you null out the test lead resistance. The ground is shared by the audio and video and any voltage drop across the ground wire caused by the (relatively high current) video signals will be picked up by the audio amplifier.

There's also the capacitance between the wires. The noise from this can be significantly reduced by placing the 75 ohm resistors in series with the R, G, B lines right where the video comes out of the console, at the mini din connector end. The capacitors can go into the SCART end. This way the video will be at 0.7 Vpp throughout the length of the cable, instead of 1.4 Vpp until right at the SCART end.

I have other ideas too, but that will do for now. Basically, it's a lot of little things that when all put together make the difference between a cable than injects a buzzing sound and one that doesn't.

Yes, I also get audio buzz from the Genesis 2 with the standard Sega AV cable. It's very mild, and it's also obvious because it only occurs on the copyright screen*, but overall the sound from this system is tinny and crappy as is a few later Genesis 1s I have. Only the first gen model I own has appreciably better audio.

Then this is what you should aim for with your RGB SCART cable. You will likely not be able to eliminate the noise completely, but there is no reason why it can't be the same as a generic A/V cable.

But most importantly, can you say that the following would possibly be the case? I am saying definitely not.

You have a Genesis 2. It has no audio issues, or very quiet audio issues (as many do.)
You have a SCART cable. You use it, it's working with audio fine.
You buy another SCART cable. It's properly grounded and shielded. You plug it into the system, and your buzzing issue is suddenly amplified. The audio channels still both work, and the picture is fine but you hear this louder buzzing with this cable.
You plug in the older SCART cable. The Genesis 2 continues to have the audio issue.
The fault is clearly the second SCART, which damaged your Genesis 2 beyond repair.

It's impossible from what I can see.

[BuckoA51]

Retro Access please please please do not give up manufacturing cables. The fact that you are here and discussing this with us puts you leagues ahead of most other e-bay sellers. Your cables are fantastic. Do I get audio buzz? Yes I do but then I have done with every SCART cable ever to one degree or another (especially on the SNES). Heck, that you came here and asked for suggestions on how to reduce or eliminate the problem shows what a great seller you are. Clearly you're in this because you love videogames like the rest of us here, not just to offload old Chinese cables like most E-bay sellers.

Frankly that guy is a complete moron if he thinks your cable broke his Genesis. It's worth trying to take it up with E-bay.

I have recommended your cables and will continue to do so on here and on my blog and on the Sega Saturn UK forums.

Please, for everyone like me that can't solder to save our lives, DO NOT STOP SELLING CABLES! I humbly beg of you

[Retro Access]

Thank you for all your input viletim, and for confirming what I was saying, this is why I wanted him to post on this board.

Perhaps I should have been more clear - that buzz with my Genesis 2 on the AV cables is the same as the SCARTs. Because I hear the buzz no matter what, I'm quite reluctant to deal with things like fixing/replacing consoles that have it. Basically my reaction to this is "if it bothers you, buy a Genesis 1." Because I hear nothing in the way of buzz from those.

We hunted high and low for good cable in the USA and settled on Belkin, which I think have a good reputation here.

edit: I am not quitting selling cables, but I needed a week's break. Not just because of this, but a bunch of eBay issues, I should not have sold over Christmas. I have "where is my item" ringing in my ears.

I would hope the Belkin cable would eliminate buzz, but I need to test it more thoroughly I guess. I am not getting any buzz on anything but Genesis 2. In different environments though, I am not denying it could happen.

[Retro Access]

re. putting the resistors in the mini DIN.

I'm going to try that, see what happens.

If anyone also knows of cable I can buy in reels in the USA I'd be grateful to know of it.

I am not able to quote properly today because my macbook has a broken touchpad all of a sudden and I can't highlight and delete anything. Sorry to not address the points made individually.

[RGB32E]

There's also the capacitance between the wires. The noise from this can be significantly reduced by placing the 75 ohm resistors in series with the R, G, B lines right where the video comes out of the console, at the mini din connector end. The capacitors can go into the SCART end. This way the video will be at 0.7 Vpp throughout the length of the cable, instead of 1.4 Vpp until right at the SCART end.

Oooh! I thought about trying this once, but didn't I think it would make a difference! I'll have to give this a shot with the next Genesis2 RGB cable I build!

If anyone also knows of cable I can buy in reels in the USA I'd be grateful to know of it.

I am not able to quote properly today because my macbook has a broken touchpad all of a sudden and I can't highlight and delete anything. Sorry to not address the points made individually.

https://edeskv2.belden.com/Products/#catid=2

Belden.... not Belkin!

[Retro Access]

Re, audio buzz with SNES - most third party cables for SNES are not shielded. I think this may be because the multi out on the console itself lacks shielding, because most other console's cables do have shielding, even crappy HK cables using inferior cabling do.

Of course, you can connect it to the ground points, which we did after finding HK cabling which could be dismantled so the plug could be used.

Customers report no buzz from these newer cables.

[BuckoA51]

Oh interesting, I have one of your raw sync cables and it definitely does buzz on my Super Famicom, but I put that down to the console rather than the cable. Have you changed your cable design for the SNES/Superfami since early November 2011? If so I'll order another one when you're back up and running and see if it's better. If not its probably a bad cap or something on my machine.

[Retro Access]

If your cable is black it's the old kind. If it's grey it's the new kind with the upgraded cabling.

[Retro Access]

It still shows you as a top rated seller, so I think wrecked might be a little harsh. I literally never look past that if its on a sellers auction page, I don't know how others might be about that though.

Zapf, here is the thing though and this is what makes top rated seller daft.

It's literally only 3 in 400 buyers needed to leave lows in any area and you lose TRS. Because I started selling in USA in late August, I still only have about 4 feedback grace. I already picked up 2 lows for item as described for really stupid reasons, I managed to send somebody a power supply not pictured in the listing for a PC Engine, but it was the correct rating anyways, nonetheless I got a low. Another one, I got a low because the guy didn't realise his SCART to YUV box needed a breakout box to output the sound, and I guess he felt I should have explained that?

I'm not bothered about the lows this negative leaver will have left, because his German feedback doesn't affect my US TRS.

I only need one more person to leave a low in USA, because they could buy two items, leave two lows and yes, it counts.

I probably don't need to point out that yes it is entirely possible for eBay sellers to find out who left lows, eBay lie when they say it's anonymous.

Just need to run a search using the star rating evaluation tool on each individual item which shows you the lows you got on that item, then run a search for a date range and cross reference it. Easy as anything.

Because of the several people with a sync issue RIGHT NOW wanting returns or tons of advice (seriously they should google it, this forum for a start could tell them loads) I am constantly worrying about that top rated thing.*

eBay really blows for selling on these days.

*I'm going to add a disclaimer here in case somebody else is reading that I'm not specifically referring to here. I don't mind sorting out these issues, and every single one is educational about the various hardware used. What does worry me though is that somebody with a sync issue might not believe me that it's a quirk of the hardware and leave a low. I am more than grateful to the people who send me info such as "Nomad does not work with sync properly" or "X-Eye didn't work either."

[retr0gamer]

Hi there,

I'm the guy bugging you about the audio buzz on my Saturn raw sync SCART cable I got at the end of November. Sorry to hear about frustrating buyers! I didn't know the backstory and thought you were maybe on vacation, so I hope I didn't cause you any additional frustration. Don't give up! We all really appreciate your work I'm really happy with my buzz-free SNES and my model 2 genesis (with some modification listed on the xrgb-mini thread)

Do you plan to get an xrgb-mini? I know I at least would pay for a short male SCART -> mini-DIN 8 cable to connect my scart switch directly to the xrgb-mini without any extra adapters.

Thanks again!

[BuckoA51]

If your cable is black it's the old kind. If it's grey it's the new kind with the upgraded cabling.

It's black, I'll order another one soon then

[RGB32E]

http://www.youtube.com/watch?v=Bxauqa7rJgI

[RGB32E]

Do you plan to get an xrgb-mini? I know I at least would pay for a short male SCART -> mini-DIN 8 cable to connect my scart switch directly to the xrgb-mini without any extra adapters.

Thanks again!

I built a couple of those for my mini recently...

[retr0gamer]

Do you plan to get an xrgb-mini? I know I at least would pay for a short male SCART -> mini-DIN 8 cable to connect my scart switch directly to the xrgb-mini without any extra adapters.

Thanks again!

I built a couple of those for my mini recently...

That doesn't help me unless you sell them!

[Retro Access]

Hi there,

I'm the guy bugging you about the audio buzz on my Saturn raw sync SCART cable I got at the end of November. Sorry to hear about frustrating buyers! I didn't know the backstory and thought you were maybe on vacation, so I hope I didn't cause you any additional frustration. Don't give up! We all really appreciate your work I'm really happy with my buzz-free SNES and my model 2 genesis (with some modification listed on the xrgb-mini thread)

Do you plan to get an xrgb-mini? I know I at least would pay for a short male SCART -> mini-DIN 8 cable to connect my scart switch directly to the xrgb-mini without any extra adapters.

Thanks again!

I'm sorry about this, I thought I answered this one on my iphone. I took a short holiday in Miami, I just checked the questions I got and this one's marked unanswered so here we go.

It sounds like the grounding on the SCART may have come loose. There's no way of soldering directly to the shielding on the plugs, I tried dremelling the shielding and still the solder does not stick so I had it attached via a looped ground wire around a hole in the shielding and soldered down as tight as possible. This has worked on the huge majority of cables but as you're the only one to mention a Saturn issue at all this is my first thought. I've improved the method used, I use spare pins taken from the scart hooked into the shielding now which does seem a lot tighter. You can send this one back for an exchange and as the other cables work perfectly using the same cabling, I think you should be OK with the replacements.

I'm going to supply the xrgb mini cabling and already have the plugs, but I got completely sidelined by reopening my listings on Sunday night only to get orders good for a week in only 2 days, as well as 20 odd more questions asking me to explain how RGB works.

The people who post on this forum are not the type of people who ask too many questions, it's the complete newbies. I don't mind helping out a little but I simply do not have time to devote to the huge amount of questions some people send me, sometimes I have no clue as well because I cannot buy every converter and every SCART TV out there. Barring some issue with the console (old capacitors being the big culprit) sound buzz on most systems shouldn't happen, the main one as I say that people ask about is Genesis 2. I think some people think the SCART might fix sound buzz, which if it's already occurring with the AV cables, it's unlikely.

[retr0gamer]

I fixed the audio buzz with my Saturn. I made two changes to the cable and tested only after both changes were made, so I don't know which one was the culprit. First I noticed that the pin at the bottom right on the mini-din end was pushed in most of the way. I pulled it back out with some pliers. Second, I scored the metal shield on the SCART lead end and soldered the ground wire to it. No more buzz!

[Retro Access]

Thanks for the input, I think I'll start filling those Saturn plugs with epoxy like I do with the Genesis 2 plugs, I didn't know they could potentially fail like that. It was really hard to find a supplier so I can't improve the quality otherwise.

It could have been the sheilding though, I think maybe I need a hotter soldering iron. What's the wattage on yours, I can't get the solder to stick to the shielding, though putting a spare SCART pin in the shielding is working well (and it's how the shielding wire is usually attached anyway, just the ones I bought don't come with a pin there.)

[retr0gamer]

I have no idea what the wattage on my iron is -- it's some cheapo iron. The solder was jumping around for a while then suddenly decided to attach near the rim of the housing.