Composite Video Output Comparison, Original Hardware, Analogue and MiSTer
10FPGA solutions to simulate classic consoles have a singular advantage over computer emulation, their ability to output analog 240p/480i audio. The two most popular FPGA solutions today is MiSTer and the Analogue consoles. However, even these impressive devices can be put to a significant test of their abilities by trying to produce the lowest quality video signal a console can produce before it gets to an RF modulator, and that is composite video.
Two console lines stand out for having rather different ways of generating composite video, the NES and SNES on the one hand and the SMS and Genesis on the other. The NES and SNES composite video is often considered a bit sharp and ugly, but the SMS and Genesis composite can be soft and prone to rainbow artifacts.
The Analogue FPGA consoles, the Nt Mini, Super Nt, Mega Sg and Nt Mini Noir support analog output, with the Super Nt and Mega Sg requiring a separate purchase, the Analogue DAC. The Analogue consoles and DAC support RGB, Component, S-Video and Composite video. You must buy separate cables depending video output option you want. There is an inexpensive adapter which provides S-Video and Composite Video output. These cables contain no circuitry in them.
MiSTer supports analog output through an Analog I/O or Digital I/O board. The RGB and Component cables are the same ones as used with the Analogue consoles. For the Digital I/O board you will need an HDMI to VGA converter. For either I/O board S-Video and Composite Video require a separate y/c adapter, and it comes in passive and active varieties.
I have taken a short capture of Mega Man for the NES and Sonic the Hedgehog for Genesis to show the differences between the two FPGA sources and original hardware. For Mega Man I am using an AV Famicom, Nt Mini Noir and the NES MiSter Core. For Sonic I am using a High-Definition Graphics Sega Genesis Model 1, Nt Mini Noir and Genesis MiSTer Core. The video output is essentially equivalent between the Nt Mini Noir running Genesis via jailbreak firmware and the Mega Sg with DAC. My MiSTer is using an Analog I/O board an an Active Y/C Encoder Board.
Audio is recorded in mono (yes, I know Genesis is a stereo console) and normalized. The original consoles sound significantly louder than the FPGA consoles with the same output settings.
Here are the timestamps:
00:00 - Mega Man AV Famicom
01:10 - Mega Man NTM
02:07 - Mega Man MiSTer
03:14 - Sonic 1 Genesis HDG Model 1
05:17 - Sonic 1 NTM
08:05 - Sonic 1 MiSTer