Both actually. I don't have any problem with online but even in single player the game feels way to different. It's not lagging at all, but it feels slow compared to my old TV.
This is really confusing to me. Can you try to dissect what you said right there for me? It's slow... but there's no lag? It's slow - but online is fine for you and it's only when you're playing singleplayer on dolphin that it's slow? That really doesn't make logical sense to me. Also, where do you live and what's your set up like? In any case, do these things if you haven't already - because if what you're saying is accurate it must just be a hardware issue;
~ Make sure your controller adapter is set up correctly, depending on which one you have and how exactly it's set up you might be causing yourself a ton of unnecessary input lag - guide for that found here
http://tinyurl.com/z3de6nu follow it closely
~ Get a Ben-Q monitor with at least 60Hz (since Melee runs at 60fps, any monitor with higher Hz [i.e. 144] is not necessary)
~ If you
do have the appropriate monitor for netplay, and are running a multiple monitor set up (such as your laptop screen being the other monitor) make sure you set dolphin to display in full screen mode on the Ben-Q, and are clicked in on that monitor so that the application (dolphin) isn't running in the background. You'd be surprised just how much lag you cause yourself just by not being clicked in on the full screen app. On top of this, run as minimal simultaneous applications as you can on your computer while playing. When I play dolphin I prefer to keep only Dolphin, Discord, and OBS running. Don't even like web browsers open or my runescape client.
~ An ethernet cable connected to your computer is a must, definitely prioritize this - -but you said your connection is good so I'm sure you already do this
~ Smashladder.com has a Smash Ladder Dolphin launcher which is a fantastic option for playing Melee online - it automatically updates with all the different versions of Dolphin for Melee and all you have to do when it updates is click download on the desired launcher and it should be ready to go very quickly (here's the link
http://tinyurl.com/yywwzrhz ) this way you can experiment to find which version works best for you, Slippi, Faster Melee, etc
Besides all that I can't think of anything else you could do in order to optimize the consistency of how Melee feels being played on Dolphin. If you do all of that, assuming you haven't already, I'd just assume it's in your head. Of course it'll never be as consistently smooth and perfect as vanilla melee, but it's honestly not
that bad. I played melee with a co worker a few months back, just after Ultimate came out, and he said it was slow. I just can't help but think that it's not
melee that was slow, but perhaps
he was inputting his inputs a tad too early or late during ongoing animations, and his actions weren't getting registered by the game as a result of that - resulting in him thinking Melee was slower than Ultimate. Maybe you're having a similar issue?