Well, two trains of thought are starting to come out
1. Getting good accordion sound
2. Effects that modify the sound beyond what it spunds like in pure acoustic mode
Part 1. Capturing good acoustic accordion sound starts out with the microphones. Basically your budget decides the kind of system you choose and it can start at $1 and easily go way above $10,000.00. Thankfully there is a kind of point where adding big money gives small gains, I found that to be around the $2000US mark. I am not saying that a $250 mike cannot sound good, but I am saying that your ears need to be pretty sharp to hear the differences between a $2000 setup and the $10,000.00 setup.
This is a huge section open to a LOT of info, lots of opinions and LOTS of people with different needs. Each will result in a very different setup.
Part 2. This section can also be split in to two areas:
A. Effects that can be added in the chaiin for live gigging
B. Effects that can be added to a track already recorded.
A. Live effects are mostly going to depend on the sound you want to generate, but more importantly, the location you are playing. A huge church, vs an open football park vs a (small, medium and/or large) club environment vs your bedrroom or livingroom are all going to demand VASTLY different effects and settings to get you the aound that you want.
For me, I will say that the environments outsiide the recording studio depend on the location, but for the most part equalization and minor amounts of reverb are what I like. Inside the recording studio, I have come to use 5 main sound modifiers to get the sound that I want:
- reverb (not echo!)
- a parametric 16 or more band equalizer
- a compressor
- a limiter
- and only when needed, a noise remover.
The brand/kinds are not all that relevant, they often all do exactly the same.
I discuss the basics of how to get your accordion recorded as well as you can using various techniques in a video I made a little while ago. Check out my blog site if you are interested.