http://chipmusic.org/forums/topic/14184 … oto-guide/

Bass Mod > Prosound Mod

I don't want to start soldering and desoldering things before I know if its worth it.

The best way to tell whether it's worth it for you is to try it out.  It's really not a lot of soldering compared to other mods, and you can test it before drilling anything in your case (if you're careful to not short anything, of course).

It does indeed reduce the dissonant hiss that can come through a lot of games on the stock output.

Just be sure that you buy some new adhesive for your screen cover; Chris (who operates 8ba) told me that the problem I had with mine not being well attached is very common, as the heat of shipping seems to make the adhesive he puts on peter out.  I personally think he should wait for his sealer to dry a bit more, as your package will arrive smelling like it. : p  But it's an extremely cheap fix and he, in general, does good work.  Very easy to contact him for customer support all through the process as well, as he's quick to respond via e-mail.

Good guy to work with.

You can use both outputs with an internal prosound mod too. The thing with the mod is that is simply bypasses the amp. The amp is there for a reason, to increase the volume. This means that without it, the volume will be very low and is therefore less suitable for headphone usage.

I understood that the point of an internal prosound was that it replaced the stock output.

The prosound does sound quieter through headphones than the stock output, but is still plenty loud enough, and I regularly use headphones with my prosound output quite happily.  Comparing stock and prosound side-by-side now and listening to Kirby's Dream Land, the main difference is substantially less hiss from the prosound output.  This is probably the biggest benefit you will get for listening to games.  My prosound is RCA post-pot.  You will certainly want post-pot for use with headphones, by the way.

You can use both outputs with an internal prosound mod too. The thing with the mod is that is simply bypasses the amp. The amp is there for a reason, to increase the volume. This means that without it, the volume will be very low and is therefore less suitable for headphone usage.

That would only apply to adding a secondary output right? If it replaces the original one it still uses the amp from what I understand, is that correct?

For a good comparison of prosound and original outputs, see Herbet Weixelbaum's page.