Well I have a theory...
It seems to me, back in the 1950s and 1960s some accordion manufactures had reached a high level of finesse in accordion design and build quality. But nothing ever really exists in a vacuum - it is human nature to build on what went before. Take the famous M & N series Super VI, they were a development on the design of the L series Super VI, and it has been said the L series Super VI (2S & 4S) was developed from an early Bell 4516 model.
Indeed Scandalli's Super VI M series went into production at around the time Giovanni Gola began to settle on the design of the Gola. Gola and his former Dallape colleagues built on the design of 1950s Dallape Supermaestro and Andy Arcari's Excelsior to create the Gola 414. Six voice bass mechanism and mute behind the grill, very much features of Excelsior. It's wonderful to think that people inspire one another to greatness.
What the Gola 414 and Super VI had in common was a compact design, (so were the early Dallape and Excelsiors) so they handled well, they were not bulky or heavy and they lay into the performer and sat comfortably. Both had aged mahogany ply casings. The design of the reed blocks were marvellous, especially on the Super VI that I believe was made of maple, and the reed blocks were fixed into place with extraordinarily strong steel springs. In fact removing reed blocks from an M or N series can be a dangerous task. It would be very easy to get injured.
Take the Gola 414, the reed blocks were topped with walnut over spruce and as highly varnished as a piece of quality reproduction furniture. Also the reeds were both waxed and nailed to the reed blocks. Naturally Giovanni Gola and Farfisa selected the best reeds at a time when the artisans really made the most wonderful reeds.
So to cut a long story short the Gola and Super VI had great design, material quality and this led to wonderful sounding instruments. Albeit they are tonally different. However, in these few short sentences about the Gola and Super VI, I have mentioned Bell, Dallape and Excelsior too. Like I say, people influence and inspire one another. This is why it is slightly sad to only mention Hohner Gola and Scandalli Super VI as great accordions. Also, in terms of actual performance, many of what I would consider top class modern instruments will have equally good handling characteristics – think Beltuna Spirit, Bugari G1, Pigini Caruso, modern Scandalli Super VI, Victoria Poeta, Petosa AM1100, Brandoni Infinity - even if the tone is quite different to the vintage instruments.
But, you know, perhaps not all decisions made by Gola and Farfisa were superlative. Scandalli Super VI and Settimio Soprani Artist VI are mainly stradella bass accordions. And as good a bass switch mechanism as they had, with 11 bass switches and bass separator, the point remains that in the development of the accordion as the complete instrument, stradella bass alone is a limiting factor. Sure, many octaves can be selected separately with the switches, but there is only one octave available at a time. Indeed, we have Anthony Galla-Rini to thank for his early work in the categorisation and arrangement of bass voices and removing the 5th from the 7th chord etc. Echoes of his work are seen in some great brands, but I digress.
Take also the Gola, there were various free bass systems made over the years but the version that became standard was the MIII system, which I think is probably the most complete of all bass systems. However, over time the most important manufactures stopped building MIII and bassetti systems (like Giulietti's). In time, if accordion manufacturers do not reconsider the decision the MIII and bassetti system like on the Gola 459 will become historic artefacts of a bygone era. I don't know why this happened but maybe manufacturers followed Ellegaard's desire to move away from MIII towards the converter system in collaboration with Pigini, who subsequently became a prime innovator of classical accordion, and the Sirius model to many the new benchmark for the classical accordion.
However, really, when we talk about innovators in converter piano accordions – in my opinion it is Victoria that came up trumps. Richard Galliano does not play a Victoria AC420V for no reason. He could get a Gola any time he wanted. He also has both a button and piano Super VI, but he still always goes for the vintage Victoria (equivalent of Titano's Royal converter). They were accordions of great quality and innovators in the converter accordion before Pigini. The astute operators like Titano made the converter accordion work for them too. Take, Scotland where I live, the converter accordion is relatively unknown and has little place in Scottish music outside of academia. Yet, take America, there will be thousands of converter instruments! Why, because Palmer & Hughes collaboration with Titano was so extraordinary they took the accordion and incorporated it into all sorts of music, including classical music, and had a methodical approach with the famous books etc. But why did quint converter catch on so well in America. Well in a country where piano accordion with stradella bass is dominant, it made for simple logic to embrace a bass system that does not diverge from stradella system. If you were good enough at stradella bass, then quint converter (with 120 bass and three octaves) would be simple to learn. If you were a wizard at 120/36 quint converter and wanted to play serious classical music, well you could always develop to 160/48 bass quint converter. In fact Dr. Palmer had a custom built 160 bass instrument decades before most of us knew there was such a thing. It would certainly be less of a struggle for the piano accordionist than learning a third system with chromatic layout. Wouldn't it? Well the likes of Steven Dominko with his wonderful Giulietti with bassetti system made a strong counter argument as did the many MIII players. Also the extended bass range of the chromatic converter is regarded by some (and disregarded by others) as one advantage over the quint system. The jury is still out. Hopefully they can co-exist.
So yes, the Gola and Super VI were great, but the bass system of the Scandalli Super VI is a limiting factor and the way the cards have fallen for the MIII - caused by too many people listening to what their accordion teacher tells them to play (converter), and manufacturers unwillingness to build MIII means if you wanted a classic accordion with converter bass the Super VI and Gola were not really the answer.
Simple, just buy a new Gola? This is not a sensible option for most people because Hohner have a strategy of having prices that are not based in the realms of reality. Simply not producing an accordion unless the buyer is willing to pay 300% of the instruments actual value is a remarkable strategy that makes demand outstrip supply and artificially pushes up the value of old Gola's. As good as they are, no 60 year old accordion is worth £12,000! And, well if you keep telling people they really are worth over £30,000 new, some poor (or rich) unfortunates will eventually believe it to be true.
I moved away from classic accordions like Gola and Super VI because I have for a long time been dissatisfied with the stradella only bass system. I wanted to explore a free bass converter accordion, and neither the Gola or the Super VI were appropriate for this. That's not to say I wouldn't consider another Scandalli model with free bass, that is a possibility. The Scandalli BJP442 would hit the mark, but in the realms of quint converter the names of Victoria, Titano (and now Pigini who are associated with Titano), Zero Sette and their American partners Petosa – these are surely heavyweights too. Essentially, I have come to realise that even a middle ranking converter accordion makes for a greatly more satisfying playing experience than any other stradella only accordion I have played - including most of the well known classics.