Let's talk about retro console audio quality/buzz

[werk91]

ones with surge protection are best avoided for amplifiers/ receivers as they can limit the output somewhat

This just sounds like bad advice; you risk irreparable damage to your expensive electronics by foregoing surge protection.

Here's some examples of what I mean: Link
And please do take this with doubt as different equipment will act differently and different countries have different electricals with various levels of ripples... Also my amplifier is a preowned Pioneer from the 90s that's stupidly cheap nowadays

[FriendofSonic]

As far as the ground loop situation, I've wondered this, but a question-- I use two surge protectors with many outlets since I've got so many power adapters. Is it safe to plug two surge protectors into the same outlet to test whether or not that eliminates any ground loop I may have? I guess I can always do a quick test.

I am not an electrical engineer, but connecting two surge protectors to the same outlet should be safe, especially since they'll mostly be populated with wall warts, and I doubt you'll have everything on simultaneously.

What you need to watch out for is daisy-chaining surge protectors and power strips and connecting high-current devices (like window air conditioners and refrigerators), as many are cheaply built and not intended for that usage.

This is what I've thought too, but then you read things online about how people swear against connecting two surge protectors to one wall outlet. I might give it a shot.

[Steamflogger Boss]

When you get into this hobby you start learning about electronics and stuff and realize how a 2€ per meter speaker cable bought from a specialized electronic supplier with the right spec is vastly superior to most of the 200€ bullshit they try to sell you as hi-fi.

Very much agree, there is a lot of snake oil in the hi-fi audio industry.

[SavagePencil]

Can someone post an example of a "good" power filtering system? I'm not sure what I'm even looking for.

[Ikaruga11]

A good surge protector that doubles as a power strip would be good enough.

[SavagePencil]

A good surge protector that doubles as a power strip would be good enough.

Wait, those will filter out ground noise?

[Syntax]

Nope but what systems do you have that are connected to earth? Most power supplies are 2 pin.

I had bad earth issues with a pc to PA sound system till I cut the earth going to the pc. My house has a bad leak I'd say.

[tjstogy]

A good surge protector that doubles as a power strip would be good enough.

Wait, those will filter out ground noise?

No, a typical surge protector will not filter ground noise. I would suggest trying something like this: https://amzn.to/2H5jdhs

If it doesn't help, return it

[FBX]

Sometimes the audio buzz can be a design oversight in the system. My Neo Geo AES had horrible buzzing in the audio, and I found out it was because I had a revision where SNK either 'forgot' to include decoupling caps, or thought they could just skip them to save on costs. Either way, I had to add them back in, and the buzzing was 100% eliminated. Sound was crystal clear. Here's a pic of the caps I added back in on the bottom of the board:



And of course for the SNES, I modded my consoles with digital audio output:



Next up, I'm working on a new audio amp circuit for the rear panel RCA jacks I installed on my Genesis model 1 VA3. The sound is clear, but at low volume, so the amp circuit is going to make it sound louder and cleaner than the headphone jack.

[cr4zymanz0r]

And of course for the SNES, I modded my consoles with digital audio output:

Me too, but unfortunately that doesn't work for Super GameBoy and MSU1 hacks on SD2SNES. :\

[SamIAm]

I was just going to say that adding more/better decoupling capacitors to the main power rails, and possibly putting in a newer 7805 regulator, might be a good universal step for all consoles. The SNES white line and PCE jail bars have been shown to be the result of noise in the power, so why not audio buzz?

One of these days, when I get around to recapping my Duo-RX, I'm going to try to track down which electrolytic capacitors are decoupling the power rail and replace some of them with OS-CON caps since they're great at absorbing high-frequency fluctuations that sail right by electrolytics. I might use higher values in places, too. After that, I also plan on replacing the 7805 and adding proper ceramic decoupling capacitors right before and after it, like it says you're supposed to do in the datasheet. IIRC, some systems didn't bother adding any ceramics around the 7805 at all, even cheap low-value ones.

[FBX]

And of course for the SNES, I modded my consoles with digital audio output:

Me too, but unfortunately that doesn't work for Super GameBoy and MSU1 hacks on SD2SNES. :\

I was working on a new mod board that mixes those lines in and resamples everything at 48Khz, but the Super Nt came out and killed the market for it. :-/

[cr4zymanz0r]

I was working on a new mod board that mixes those lines in and resamples everything at 48Khz, but the Super Nt came out and killed the market for it. :-/

I'd be interested, especially if it was smart and wouldn't let analog noise seep in when not using SGB/MSU1. I don't buy into all this "100%" compatibility FPGA snake oil for my primary console (Please people, don't try to debate me on this. I just have a mental preference towards original hardware and I'm kinda anal if I ever notice a discrepancy in something supposedly 100% compatible. lol)

I was just going to say that adding more/better decoupling capacitors to the main power rails, and possibly putting in a newer 7805 regulator, might be a good universal step for all consoles. The SNES white line and PCE jail bars have been shown to be the result of noise in the power, so why not audio buzz?

One of these days, when I get around to recapping my Duo-RX, I'm going to try to track down which electrolytic capacitors are decoupling the power rail and replace some of them with OS-CON caps since they're great at absorbing high-frequency fluctuations that sail right by electrolytics. I might use higher values in places, too. After that, I also plan on replacing the 7805 and adding proper ceramic decoupling capacitors right before and after it, like it says you're supposed to do in the datasheet. IIRC, some systems didn't bother adding any ceramics around the 7805 at all, even cheap low-value ones.

I've considered trying to see if a 78S05 regulator might help some consoles, possibly not being limited to just audio (like the pesky SMS jailbars). They're cheap enough that even if they don't end up doing anything noticeable it's not like i'd be out much. I also had no idea that the 7805 datasheet called for decoupling capacitors or that some consoles didn't include them. Do you know of any specific consoles that excluded them?
I'm fairly good at modding/assembling/installing things, but my knowledge of the underlying circuits is pretty primitive. We need a "Game Consoles, Analog AV circuits, and You" online course