Just joining this older discussion re basses. Speaking as an accordion teacher for decades, (even had mine own school years ago) - I agree with Davidplaysaccordion that practising the major scale is a great way to learn the position of the buttons - but both up and down of course.. and that may be a challenge for some.. in terms of patience? The following comments the experienced player will already know...
In reading over the threads, I didn't see any reference to that wonderfully creative original system of the bass keyboard with reference to the musical Circle of Fifths.... As we know, key of C major has no sharps or flats, one sharp - G major, 2 sharps - D major, 3 sharps - A major etc And going down below C, 1 flat - F major, 2 flats - B flat major, 3 flats - E flat major. etc. Further, the counter bass in each key is always the third in the scale, and the bass above the sixth etc. SideBar -- (Reminds me of the pioneer accordionist Pietro Frosini whose first Excelsiors were made with the bass section having individual notes - before the Stradella system was implemented widely-- and he played his chords using all three fingers!! )
And a further previous comment was that once the pattern was learned, it held in all major keys. Of course. For advanced players, learning the minor and chromatic scales both alone and together really makes one appreciate how more easily all compositions can be performed.
Also from what I've seen and heard over the years, the novice accordionist often wants to play songs almost from the first picking up of the instrument. I did too, but my second teacher - Al Viola - insisted on learning right and left hand scales first as "warm-ups". Still do that today in the rare times I pick it up.. And especially in the keys of the piece being learned.. Like athletes before a game.... fingers, hands, arms etc are muscles too!
Maybe unfair comment, but I often felt that the accordion is the easiest instrument to play poorly and the most difficult to play really well.
It may be of the only one which has a different keyboard for each hand, and it's virtually impossible to see one of them .. except with a mirror of course, but that also reverses the image... e.g., try using scissors in your left hand and cut a simple strip of paper using a mirror!!
I give a lot of credit to those who persevere. It's worth it!!
My accordion "Bible" in the early years was Deiro's Road to Velocity, then later Charlie Nunzio's Hanon Studies and Frank Gaviani's Modern Technique. Those 2 likely have almost every conceivable exercise for each and both hands. The last 2 I still have and use - not everything of course - but certain parts to warm up. Another excellent manual was Mastery of the Basses for the more advanced players..
I must add that most of my playing career was preparing for competitions or concerts. Competitions demanded you play exactly as written no matter how almost impossible, or accept the "wrath" of the adjudicators!! Very few of those, but they were there ---- I know!!
Incidentally, found a comment hidden in some music written by Charles Magnante when adjudicating at a Kiwanis Festival in Hamilton years ago. Typical Magnante - gracious and helpful in his commentary to encourage the performers!!
And I can't help but make a comment regarding another thread re the sequence of bass reeds. I may err but I believe that at least one set of bass reeds is in a different order in order that, when playing left hand scales in the different keys, one can hear the scale as 'normal' from top to bottom.
Otherwise if all reeds were in identical order in the blocks, there would be a 'jump' from a middle note back down to the lower one... to simplify the concept.. This may generate some reaction, but that's what forums are all about, as I've been informed.
Hope above is of some interest, if not I'll back off on this topic for now....
