Converter (Bass) - Needed ? Must ? Better ?

[debra]

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So what`s better/different in Russian or mirror, does it offer any playing advantages ?

Some people find one system more logical than the other. (That goes both ways!)
A lot of Russian music and arrangements are written with the Russian system in mind.
Whatever you can find should be equally usable for everyone except maybe the greatest virtuosi.

I mentioned the note amount of the bass side, though it also means there are more notes on the right side too.

58 is standard on larger CBA instruments. The 580 has 55 on the lefthand side. The 540 has 49. It does not matter too much as you are not likely to play very high notes on the lefthand side and there is an L and M so on M you can go pretty high. A Russian Bayan is always LL so with 58 notes it goes even less high than the 540 does on the M register.

I found a 580 for about 5,000 euros in Poland, which is the cheapest relatively new Artist I found, but considering the extra 3.5 cm height and extra 1.3 kg compared to the 540, I`m thinking it won`t be the best option for me spending so much.
My first Accordion budget was 250 euros and I thought it wont exceed a 1,000 in the next 5 years, but after hearing the difference and feeling controllability (it was in PA)...

When comparing the 540 to the 580 yes the 580 is larger and heavier but for someone who is 1m75 the 580 may actually be a better fit. The 540 is only 41cm and that makes it nicely compact but harder to use the chin switches.
Dont just assume that smaller is better.

I also found another one for 4,500 euros, he doesn`t know the model but it has 11 regs, 21.5 cm thick and weights 12 kg (so he claims). As long as I know, Bugari cassotto models usually don`t come in 11 regs, but with 13, 14, 15 (13 or 15 in Conservatory CBA).
The label states Conservatory, the owner claims it has a Cassotto but he is an amateur himself and I don`t trust what he says anyway. I suspect it`s a Cassotto-less 504, he said he`ll send me pics of the inside in the next days, I`ll post here.

Very strange that someone does not know the model of their accordion. Conservatory only means that it is a convertor instrument (in Bugari terminology). All convertor instruments have that label and have no label that indicates the model. The original invoice should mention the model number though.
11 registers suggests no cassotto, and 21.5cm thickness rules out a 504. It is more likely a 360 seniorfisa and in that case the price of 4,500 is very likely too high.

 

[Auser]

The 540 is only 41cm and that makes it nicely compact but harder to use the chin switches.
Dont just assume that smaller is better.
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Very strange that someone does not know the model of their accordion. Conservatory only means that it is a convertor instrument (in Bugari terminology). All convertor instruments have that label and have no label that indicates the model. The original invoice should mention the model number though.
11 registers suggests no cassotto, and 21.5cm thickness rules out a 504. It is more likely a 360 seniorfisa and in that case the price of 4,500 is very likely too high.

I think I care less about the chin registers (do I ?), than the size & weight, and being 1.75 is quite average.

That unknown model seller, instead of sending me the photos, suddenly said it was sold. I had a strange feeling about it since the beginning, and I think I was right. He first sent pictures of his registers and acc apart, then on the video I saw those are different registers.
So I`ll keep looking.
Are there any types of Artists/ Champion Cassotto models that have 11 regs ? Usually I immediately discard those posts as I think they have no Cassotto.

 

[debra]

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I think I care less about the chin registers (do I ?), than the size & weight, and being 1.75 is quite average.
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Some people (like my wife) dont like chin switches and would even rather use them with their hand than with their chin. But for the most part, once you get a bit used to them they become a invaluable tool. You can change registers without taking your hand off the keyboard and without any interruption. A lot of arrangements and compositions for accordion do not consider that you may need time to change a register. You need chin switches to be able to play these pieces well.

You really really need to handle, try and listen to an instrument before buying. You can get away with doing this with a different copy than the one you are getting, but an accordion is so personal there is really no advice we can give you other than this to help you select an instrument without the try before you buy option.