Crunching the Numbers on CBA

[Ffingers]

Here's a concept from Soviet past. ~3 octaves in the left, ~3 octaves free bass in the right. I believe it had a catchy name of "Semi-Bayan".
If this was a high quality box with good reeds (2 voices in unison) and 5-row keyboards, I think it would be a winner. Perhaps, only 1 voice in the left hand side, but stick it in cassotto. Perhaps, Moschino in the left hand side (I'm still working towards this one).
I agree on the big boxes - they are way too bulky & heavy, and I don't have any bats in my family, so really don't need the ultrasound octaves. The lowest free bass octave sounds OK, but I can't see it being used very often, so that can be left out too. I think the accordion reed performs well in the middle. If you have C2-C5 in the LHS and C3-C6 in the RHS, that gives you a huge range - way more than most other musical instruments.

...Yep, I've started drafting a design of my dream acoustic accordion...
...I even tried making some reeds by hand with reasonable success (at this point, purely for educational purposes)...
But the build won't be happening any time soon, if ever.

I recently bought something similar from a secondhand dealer in the Ukraine.

It was packaged remarkably well and arrived in good condition and well tuned.

I now have to prise it back out of my music teacher's hands!!

https://www.etsy.com/au/shop/MarketFleaShop if anyone is interested.

 

[debra]

Returning to the original question... the 87 button keyboard, which consists of 17 + 18 + 17 + 18 + 17 buttons... it can accommodate 17 + 18 + 17 = 52 notes at the most. This then requires 26 notes on a reed block in order to fit everything on 4 reed blocks for a 4-voice accordion.
If you want such an accordion with 52 notes, Victoria makes one that comes close: the "Solista" model, with 53 notes and considering its dimensions (48 x 20) it cannot accommodate more than 4 reed blocks (2 in cassotto, 2 outside).
52 notes is more common in "French" models, but they are less tall (in the playing orientation) and use 3+3 reed blocks, making them deeper (wider).

 

[tcabot]

Tula still makes these. They advertise them as "baby button accordions for young students". Both a 3-row model (BN-56) with 30 notes in each hand, and a 5-row model (BN-46) with 46 notes in the right and 37 in the left.

Good find. They also have BN-55 with a converter.
Unfortunately, from what I've heard from a couple chaps who buy these for schools, the student models build quality is rather poor, QC is poor and the tone varies from "acceptable" to "completely dead". The conclusion was that they'd much rather buy one or two good used instruments for the same budget, but the school policy did not allow it.
The 3-row left keyboard is not any better than the free bass I can get on MIII either.
If I was to start accordion from zero, this would be a good starter instrument I guess.

It seems that nobody is making the same type of an instrument but with pro-level reeds & mechanics.

 

[Walker]

Returning to the original question... the 87 button keyboard, which consists of 17 + 18 + 17 + 18 + 17 buttons... it can accommodate 17 + 18 + 17 = 52 notes at the most. This then requires 26 notes on a reed block in order to fit everything on 4 reed blocks for a 4-voice accordion.
If you want such an accordion with 52 notes, Victoria makes one that comes close: the "Solista" model, with 53 notes and considering its dimensions (48 x 20) it cannot accommodate more than 4 reed blocks (2 in cassotto, 2 outside).
52 notes is more common in "French" models, but they are less tall (in the playing orientation) and use 3+3 reed blocks, making them deeper (wider).

Very interesting Paul. So it seems that Victoria tend to make their 4 voice (87 button instruments) slightly shallower (20cm, with cassotto) than the other makers such as Bugari, Pigini or Scandalli who are 21cm deep for a non cassotto 3 voice instrument with 52 notes (or 4 voice with 46 notes). I also notice that both Victoria's 3 voice (converter and standard bass) accordions have the depth of 20cm, regardless of whether they have cassotto or not, though their Signature model made for Galliano (cassotto) with 3 voices is 19.5cm depth...

From what I have read here, it seems accordion makers have the option of designing 87 button instruments with 2 reed-block-sides per voice or 3 reed-block-sides per voice. It would appear Victoria tend to use 2 reed-block-sides where possible on their instruments with even 53 notes (88 buttons). The other makers seem to prefer to increase the depth of the instrument (3 reed-block-sides per voice) where there is more than 46 notes...

I am beginning to understand what losthobos is saying...

Whoever opened up the accordion would have found it easier to open a can of worms...

 

[Walker]

...actually, now I think about it, having 3 reed-block-sides per voice makes sense on a button accordion because you have 3 rows of buttons as the foundation of the instrument. Maybe it's one reed-block-side per row...

 

[tcabot]

Yep. That's the standard non-cassotto arrangement.
With cassotto, the most solution is to use a cassotto PA with 2 rows, so the rest of the box does not need to be re-designed. Apart from bayans, where you see 3-rows even in cassotto.

 

[debra]

...actually, now I think about it, having 3 reed-block-sides per voice makes sense on a button accordion because you have 3 rows of buttons as the foundation of the instrument. Maybe it's one reed-block-side per row...

You guessed it: each row of buttons corresponds to a reed-block side (times the number of voices). And it becomes a small problem with cassotto accordions because with three blocks in cassotto there is a clear difference in sound between row one and row three of the buttons (with row 2 sounding close to what row 1 sounds like).

 

[Walker]

So does anyone have a preference on 87 button instruments; whether you prefer to have your 'notes' (per voice) spread over 2 reed-block-sides or 3 reed-block-sides?

Your thoughts on either non-cassotto & cassotto instruments within the 46-52 note range & with either 3 or 4 voices would be appreciated!

 

[debra]

So does anyone have a preference on 87 button instruments; whether you prefer to have your 'notes' (per voice) spread over 2 reed-block-sides or 3 reed-block-sides?

Your thoughts on either non-cassotto & cassotto instruments within the 46-52 note range & with either 3 or 4 voices would be appreciated!

My experience has been that on cassotto instruments with 3 reed blocks in cassotto the (unwanted) difference in sound between the first and third block in cassotto is larger than with instruments with 2 blocks in cassotto. This sound difference (or absence thereof) is what I look for in particular when trying out a new accordion. So far the accordion that pleasantly surprised me the most was the Beltuna Prestige Paris 4 (with 58 treble notes). It had the most "equal" sound I found so far. On button accordions in general avoiding a sound difference is more important than on piano accordions, because on a PA the sound difference is just between white and black keys (with a few exceptions on accordions that put some white key notes on the black key reed block), but on a CBA it's spread over both white and black.

A similar difference in sound also exists in non-cassotto instruments: to fit more reed blocks some blocks are in a position where their sound is influenced by keyboard and register mechanism (and grille) whereas the other blocks can radiate their sound more directly. In the old days manufacturers made use of this influence to put all the L reeds on blocks with the "impeded" sound (acting as a bit of a resonance chamber) and implementing a "declassement" but this was later abandoned because too complicated.

For an accordion with 46 (or a bit more) notes spread over 2 block sides manufacturers typically also use larger buttons in order to look nicer on a taller instrument, whereas with 52 (or more) notes spread over 3 block sides manufacturers typically use smaller buttons. The difference in button size may be important for people with different size hands/fingers. I find the larger buttons more comfortable to play than the smaller buttons. (And as I have accordions with not just 2 but 3 different sizes of buttons, it makes switching between instruments a bit harder too.)
If you pay attention you will for instance notice that Richard Galliano's favorite Victoria accordion has larger buttons than the bayans you see played by many bayan players.

 

[Walker]

Thank you Paul, excellent detail.

May I ask, what are the two typical button diameter sizes for instruments with 46+ notes compared to 52+ notes?

Thanks again.

 

[tcabot]

On a sample of only 2 accordions, my accordiola has 46 notes, 5 voices with double cassotto in the right and 5 voices in the left. The accordion feels manageable and well-balanced - in fact, with one voice removed from RHS, I'd say it feels only slightly heavier than a 3-voice non-cassotto box with 56 notes.

A 56 note excelsior with 5 voices & double cassotto in the right, chin switches and double-octave two-voice MIII in the left feels like I'm trying to hold a grand piano on my knee .

Since both boxes need work that I'm slowly chipping away at, I spend most of the time playing a Roland, which is way too light for my liking - I think an accordion needs some weight to it. But I'm quite a big guy.

Good point re buttons. Traditionally they are about 15mm and well-domed, but the excelsior has got 16mm flat-tops and I find them way more comfortable. It also has got what must be the smoothest rhs keyboard mechanism in the world, so that might play a big part in the feel & comfort.

Note: in my case, it's the 46 that's got traditional smaller buttons and 56 that's got larger flat-tops. The traditional ones are mother of pearl though while excelsior is just good quality plastic

Another thought: I haven't measured the buttons spacing, but I think it's the same on all 3, which is about 18.5-19mm(?) between centers. Some accordions (Hohner?) have got larger spacing - 20mm perhaps?

 

[Siegmund]

My sample size is only one: my (old) Weltmeister is 16mm diameter and 19.5mm spacing.

When I test-drove a Pigini and a brand new Weltmeister last month, I had the impression the buttons were closer than I was used to and I was having to make little adjustments all the time to hit the right buttons. Perhaps 18.5mm has emerged as a modern standard.

Edited to add: it's clearly the reeds, not the buttons, that is the limiting factor here: 61 buttons at 19.5" spacing would require 406mm/16" and my instrument (like many others) already stands 450mm tall.

 

[debra]

There is indeed the issue of button size *and* spacing...
The standard "large" buttons are 16mm and small buttons are 14mm. But buttons come in all sizes from smaller to even larger, and all in 0.5mm increments. Spacing varies as well: in the same space my bayan fits 5 buttons my bass accordion only fits 4...
Manufacturers essentially choose a size and spacing for buttons such that 1) there is enough room on the keyboard to fit all the buttons and 2) the buttons are large enough so that the keyboard looks reasonably "full". The latter is the main reason why standard 46 note keyboards have large buttons plus extra dummy buttons. It looks good and the keyboard would look too small if it only had the functional buttons.

 

[debra]

...

Edited to add: it's clearly the reeds, not the buttons, that is the limiting factor here: 61 buttons at 19.5" spacing would require 406mm/16" and my instrument (like many others) already stands 450mm tall.

Yes: the added width of the reed plates that need to be fitted on a reed block side (for the L reeds which tend to be the largest) is the limiting factor. Which is why the accordions with 28 notes on a reed block side need to use extra narrow reed plates and a near zero gap between them.
On Russian bayans the problem is not the number of reeds but the width of the reed tongues. Real bayan reeds are wider than Italian accordion reeds, and as a result these bayans come with reed blocks where the walls between notes are at most 1mm thick. You cannot fit Italian accordions on these reed blocks because the walls are too thin to still support the individual-note reed plates.

 

[tcabot]

Remember to get the correct system this time(B ).

 

[tcabot]

Are you actually looking to order a custom button box and switch from PA?

FWIW, I'd go with 46 note treble in any case - drop the ultrasound and the lowest notes (you'll have better, bigger reeds for the same notes in the LHS anyway, so you're not forgoing any range).

I think I am still on track to try the Moschino layout by the end of the year (and yes, it will have MoP buttons ) - if you happen to travel to Central Belt, you'd be welcome to give it a bash. I've fannied about a little bit with Bayan & Quint on the Roland and MIII on acoustic, and I am still not convinced by any of them - at least on paper the moschino looks like "the one". If not, then a 5- or 6-row free bass would be much better than 4 on a converter.
I don't know about the C/C system combo, but any other set-up requires learning a new system for the LHS pretty much from scratch. E.g. B/Bayan is no easier than B/MIII or B/C as RHS fingerings are completely different anyway. If anything, quint seems to be the most natural at first for a stradella player.
I am just drawing the parallel between playing a 3-row RHS and a 5-row RHS and just how much easier and better it is when you have doubled rows.

In any case a purely free-bass box is likely to work better, weight less, cost less, be easier to play and be less likely to break...

 

[Walker]

Hi tcabot,

I wouldn't want to move away from the PA but I will happily add CBA. I guess I am not really an 'either-or' kind of person... I like to acquire new skills but not at the expense of loosing others...

Believe it or not there are some lovely virtues to the piano accordion that are not met by the button accordion. Likewise, there are many fine things about the CBA that the PA cannot match. However, as a second instrument, I feel that the CBA C system (with mirrored C system bass) is an engaging and elegant instrument with which to interpret music. However, I do recognise that PA with Quint converter is an instrument of significant contrast to CBA C system converter. I feel that such markedly different treble & bass keyboards makes for a vast learning experience - and that appeals to me.

Regarding instruments. I don't plan on buying any special custom built accordions. If I could find a nice second hand instrument that would be fine. Failing that, when the time is right, I would look for something new like the Bugari 380/SP/C that has a similar specification to the instrument I outlined above.

It would be cool to meet you some time and try out the Moschino too.

Thanks again,

W.

 

[saundersbp]

Failing that, when the time is right, I would look for something new like the Bugari 380/SP/C that has a similar specification to the instrument I outlined above.

Excellent choice!

 

[tcabot]

I wouldn't want to move away from the PA but I will happily add CBA

Well, you got me thinking about Kravtsov's keyboard, which sits somewhere between the PA and the CBA, but was developed to allow PA players make an easy shift to it (in only about 2 weeks according to Kravtsov, as all PA fingerings can be played on the Kravtsov out of the box). The LHS free bass converter is a mirror of the RHS.

Unfortunately, won't be easily available to purchase at the moment, given the war.






Fingerings notes (use google translate):

Аккордеон Кравцова Возможности клавиатуры

Возможности клавиатуры Кравцова Свойства

www.accordionkravtsov.ru

 

[losthobos]

@Walker
How come you've not considered the French 3x3 system....get a map and check out....best of both worlds...3rows of freebase and 3 rows chords...
And you'll get the pimpest of mother of pearl deco ...