QUOTE(DarthMingus @ Nov 19 2009, 10:12 PM)

Since when is the Xbox output blurry? I have an HDTV and its nice and crisp as long as you turn the filtering off in the emulators.
Xbox MAME output via SDTV is extremely blurry due to a combination of bilinear filtering and flicker filter. Turn off flicker filter and the screen flickers, while turning off bilinear filtering causes geometry deformities. The reason I mention SDTV first is because most actual MAME cabs I'm familiar with tend to run SDTV or an arcade monitor.
HDTVs are more forgiving with flicker filter, so it can be turned off. Turning bilinear filtering off, however, removes blur at the expense of geometry deformities due to the game resolution not being in alignment with the emulated video output. Bilinear filtering helps mask this, but at the expense of texture shimmer and blur. Texture shimmer occurs when bilinear filtering attempts to recreate the missing geometry on the areas of the screen where the geometry is missing. For example, if 1 row of pixels are missing, bilinear filtering may attempt redraw it with 3 blended pixels. Whenever certain textures scroll past that area, the screen shimmers. Static screens like Ms. Pac-Man or Donkey Kong aren't as noticeable since they don't scroll.
So yeah, you *can* have a sharp picture if you run HDTV and don't mind deformed graphics or you can add some blur & shimmer with bilinear filtering. Running a software filter like Simple2x helps alleviate some of the blur, but it doesn't solve the geometry issues that exist in the Xbox ports of MAME.