Hi there. I'm an accordion player from Melbourne, Australia, About as far as you could get from either Quebec or Louisiana for that matter. In 1992 I had the great fortune to travel to both places. In Louisiana I picked up a C Acadian that I had ordered from the Great Marc Savoy. Left handed too!
In Quebec I went to the Montmaginy festival. Marc happened to be attending that year as well. I attended workshops by Dennis Peppin, a great Quebec player who was playing a D Acadian as many of the Quebec style players were at that time.
Given the similarity to Irish Music, I don't find it too suprising that the qualities being built into the Quebecios Accordions these days are just about the same as what you would expect in a good Irish Accordion. Lightning fast action. Low button height. Light weight. Great Reeds (often supplied by FRM Enterprizes.) Good for the speed and high ornamentation that is built into these celtic musics.
The technique involved in modern Cajun Accordion playing seems to require a different weight balance in the Accordion. It is a different music after all, and believe me, you need a whole lot of different skills to play it than for any other style of Accordion music. Maybe the weight factor is one aspect of Accordion design that is needed to achieve the unique style that is todays Cajun Music.

I've live in Quebec for 30 years and yet play cajun music (for 15 years). I know quite a few single row players here that play quebecois trad music. The boxes look similar because they were both based on designs adapted fron the european single row, 4 stop models available before the war. They call them melodians over there. Here, Messervier and Melodie are supposed to be the best. Most player here use key of D boxes. The quebec boxes are faster, more responsive than the louisiana equivalents. the quality of woodworking is beautiful, but I like the esthetics of good Louisiana boxes just as much. The best Quebec boxes have bellows made by the makers.This doesn't mean that Luoisiana accordions are lacking, the good ones are great for the style. I think a Messervier box tuned cajun would be awesome and a dangereous instrument in the hands of a Ray Abshire!
There is a site for the SPDTQ that holds dances, puts on the trad festival (La Grande Rencontre) in Montreal and has the music/dance school L'École des Arts de la Veillée where you can study with master players here.

here is the website for these activities:
http://www.spdtq.qc.ca/

Harlan: Are you aware of any learning video for Quebec style (like equivalent of Dirk Powell's for Cajun style)?

Salut Maz-
Je te suggère de contacter le SPDTQ avec cette question par le lien que je ai donné dans mon dernier message.

For those who have not actually had one in hand. Firstly, they are very well made and depending on the builder, they are somewhat smaller than La built accordions. The treble keyboard is more like a modified Hohner keyboard in being that it is a shell with the wooden part of the valve arms hidden below the face of the keyboard. For the most part the bass box is the same as a La. box. The large majority don't install registers at all. The treble face plate is usually solid wood 3/16" thick. Air holes in the face plate on most are 7/16" in size on 3/4" centers. They usually have the standing reed blocks removable and sometimes with some builders all the reed blocks are standing and removable. Many make their own bellows. Treble valves are most always varnished natural wood and some use wooden buttons. Ebony etc. Finish on their accordions is very good. Ouilette ( Melodie) accordions and his brotherinlaw also make furniture so have a complete woodworking shop and spray booth for use in making accordions. Tuning is completely different than La boxes. The accordions are loud but harsh sounding. Not suitable for cajun music if you want to sound traditional. Even with retuning, IMHO, they would not sound very cajun, for lack of a better term. With no registers and being smaller they are lighter. Treble keyboards are fast and could easilly be used on La. made accordions but would those playing cajun music accept them.????? Many Quebec builders don't use metal corners and some don't use bellows straps but use an inside hooking system found on some piano accordion.

These observations were made while exhibiting my accordions in Quebec and repairing Quebec accordions. Unfortunatlly I no longer have the specs. but these are well made boxes. The style could be adapted for La. made accordions but would they sell. It's seems that those interested in cajun music want traditional looking accordions.