What do you mean by low level? I emulated some PS1 games and they were right on the money in terms of visuals. Hell, the gamecube games I've emulated look great on the PC/monitor setup although the sound and speed are jittery like hell.
I mean that the emulator isn't doing exactly what the console does, it's loosely interpreting the software and translating it to an x86 PC architecture so that it can run on our everyday CPUs and GPUs.
They work great, but they're far from perfect, there are timing discrepancies, glitches, and changes to sound and visual effects.
In many cases an emulator can be used to make a game look better than it did originally, which is great, unfortunately it's not perfect, and can cause problems in a lot of cases.
Even in projects that are insanely dedicated to behaving exactly like the console, like bsnes, there are still timing discrepancies because you are running it on a PC architecture with a multitasking OS running in the background, and even in a dedicated project like that bugs still arrive from time to time.
The best solution is always going to be the real system. That's not to say that emulators aren't a great alternative, but the best solution is always the original.
If you were trying composite cables, it isn't the TVs fault. Composite damages video internally by the console. BEFORE it reaches the TV. And composite is 480i, PS3 doesn't get to use its HD upscaler with that cable. Only adding to the problem.
HDTVs also are much more sensitive to the quality of the original signal they receive. Sending a bad image to an HDTV, will get bad results. A lot of the flack HDTVs get from retro console users has roots in ignorant setups like using composite where avoidable. It's actually not near as common as believed for an HDTV model's screen panel itself to be so poor to where it would detriment gaming. Not that it doesn't happen.
Using HDMI/component/etc helps by providing clearer source images. External scalers may offer even more. It'd night and day the kind of improvements higher end devices can make to certain consoles when configured correct.
From the way he was describing things, it sounds like he is most likely hooked up through HDMI or Component, because he described switching to composite (presumably the only input he has on his SDTV)
while composite video does severely degrade the signal, I can assure you that's not the worst problem going on here. I work with a lot of systems with rgb, vga, and component, which are great source signals.
Even they look fairly poor when plugged directly into an HDTV. The reason for this is that HDTVs have cheap upscalers built into them. You have to upscale a standard definition signal to a high definition one for it to appear fullscreen on an HDTV.
there are often a lot of rounding errors, and pixel artifacts because of that, completely independent of composite video artifacts.