Correction....I've been playin On a "D" accordion and "C" accordion.....you know, the two basic key accordions most people should start with.

I love the sound of a B-flat, but I once had the opportunity
to play on an accordion(Acadian) in the key low G and that was amazing.
I don't know if that's what you want.
Good luck with searching

Thank you melo! That's the kind of information I'm looking for. I've only come across the knowledge of these low key accordions as of late. So far including what you just said, there is a low d, a low f, and a low G accordion. I am looking for power and resonance and responsiveness. I spent some time playing a low F at Martin accordions. It was a very interesting key accordion to play on. But it is sort of out of my singing range. I am going to look into that low G. For anyone else reading this, don't give up on me. I'll take any input I can get.

As for the B flat., that is the one other key that I am familiar with. I had one that did not agree with me, and then I have played on one and I thought it was the best accordion in the world! And I know b flat can be used to play zydeco are Creole music. I'm keeping that one on my list too.

Aw come on guys and girls. You mean to tell me that nobody visits this site anymore? I know that some of you are holding out information on me. Can nobody talk about the effect of shaved reeds on the sound and feel of an accordion? Can nobody speak of how it is that I've been playing for 35 years and never heard of an accordion made in the key of low d, low f, or low g? And why is it Bb flat instead of just B? What happens if you make an accordion and tune it to B# sharp? Can you take a C accordion and retune it's reads to be a Bb flat? I'm not asking for my own good, I'm asking for the good of everyone for some got dam answers!!

Hey Greezy, I just got some information from Vincent Accordions! I figured that you might be interested in knowing that he said that the Cajun diatonic accordion can be built in 12 different keys!!

G,G#,A,Bb,B,C,C#,D,Eb,E,F,F#

And that's not even mentioning
low D, low f, and low G! And there may be other low keys that I don't know about yet. Good luck in finding your most resonant preferred key. I too am on the same search. And from the looks of things, we have 12 different keys to have to choose from plus the low-key genre! Holy mack!

Thanks Jude! WTF??!! That is very surprising information! I wonder why it is not more known or talked about? Sounds like some information hoarding has been going on to me. So let me get this straight:
ALL POSSIBLE ACCORDION KEYS

G, G#, A, Bb, B, C, C#, D, Eb, E, F, F#

LOW D, LOW F, LOW G... so far....