why more cassottos with L reeds rather than M reeds?

[Ganza]

By definition, are L reeds not mellower than M reeds, as they are lower in the pitch, and the least mellow are H reeds.
Why then do most accordions with 1 cassotto put the L reeds in there? Doesnt a M reed need to be mellowed more?

 

[JIM D.]

You must understand that the accordion as we know it, that contains for instance 3 sets of reeds, have all the reeds of same quality and construction. The (L) set will play in a low octave, the (M) set plays 1 octave higher a the (H) set will play 2 octaves higher.
The mellow sounds they all produce are for the capability of an accordion to produce the octaves that can be almost obtained from a 88 key piano. The sounds these metallic free reeds produce will vary on the area they are placed inside the instrument and the the construction and quality of the accordion.

 

[donn]

No, it makes sense that it's the Low that needs to have its high end muffled - so that its timbre comes out mostly below the sound of Mids and doesn't drown them out. Of course there are pros and cons, some prefer the plain open L sound, and I guess there are a few higher end boxes that put an M in cassotto also.

 

[debra]

I have never seen an accordion with only one reed in cassotto where that reed was not the low (16') reed. The reason is simple: the 16' reeds in cassotto produce a more mellow tone but the effect of cassotto diminishes as the notes go higher. So by the time you reach the highest notes there is not much of a difference between the notes on 16' in cassotto and the same notes on the 8' register (played one octave higher so they sound just as high) and not in cassotto.
Today most accordions with cassotto have 2 reeds in cassotto. 16' and 8' in cassotto is most common but there are also accordions with 16' and 4' in cassotto so that when you play 16-4 or 16-8-4 sounds less sharp.