Pro Sound
Pro Sound mods for the DMG are as routine and varied as they come, with most usual output sockets covered. There are a few ways to do this. Some like to tear out the speaker. Some like to have it so the speaker turns off when plugged in. Some prefer 1/8 inch jack inputs on the bottom right, or RCA phono on the top. There’s a few standard ways to do this and a few leftfield styles. All are legit though, avoiding the perceived sibilant noise associated with the headphone output. Some mods make this louder. Some mods make this cleaner. We’ll attempt to cover a complete list of these methods.
History
The Pro Sound first use or the origin of its name is attributed to trash80 [1][2][3], by reverse engineering the Gameboy Color, paving the way for bypassing headphone sockets on almost all the Nintendo handheld Gameboys. There are a few subjective opinions behind prosounding. Here’s a decent sound comparison article.
Variations
There are different ways to pro-sound and there’s no real ‘right’ or ‘wrong’ way as people have different opinions of what the mod means. Some prefer to remain un-modded, preferring the noisier, louder sound of the headphone jack. There also occurs a whine in certain mods that can be EQ’d out for crystal clear recording. We simply want to document the methods and not be drawn into preferred methods here.
Mini-jack
The most common Mini-jack (1/4-inch jack) mod is mounted in the bottom-left hand corner. Most commonly threaded screw mini-jack ports are implemented and tightened on the outside. Some are glued in place (I advise a small amount of hot-glue so that the wires inside are not twisted when screwing in place)
Hand-Held Legend Tutorial on Instructables:
RCA Female Phono Plugs
Commonly mounted on the top. These are the left and right phono outputs commonly found on line-out / line-in mixers.
Hand-Held Legend Tutorial on Instructables
Hybrid
Both versions of the Mini-jack and RCA mod in one. An example of this is by irq7 at Noizebox.
References