Sample pack for NI Kontakt is designed specifically for NI Kontakt with the appropriate interface and capabilities and may be used only in NI Kontakt 5.02 or higher version while free Kontakt Player is not supported.
SF2 sample is a version of the classic sample properties which can be converted into almost any sample format, but, compared to the NI Kontakt version, has limited possibilities. For detailed information please read User Manual for our sf2 products.

All of the accordion models have been made in the same way and only difference is in sound. Tastes and needs differ, and we will provide some basic differences:
Guerrini Professional has some metallic but soft sound.
Guerrini Superior 2 has more "wooden" and wide sound.
Guerrini Champion has more hard and "strident" sound.
All those three accordions are 4-voices with 2 cabin (soft) and 2 out of cabin (sharp) voices, in right hand.
In Guerrini buttoned accordions there are Basson (low-soft), Sopran (mid-soft) in cabin and Clarinette (mid-sharp) and Piccolo (hi-sharp) as out of cabin voices.
In Guerrini piano accordions there are Basson (low-soft), Clarinette (mid-soft) in cabin and Sopran (mid-sharp) and Piccolo (hi-sharp) as out of cabin voices.
Register (sound) that you described looks like all voices are active, so it means "Master" register.
I hope it is more clear now.
For detailed information please read User manuals that you can download at each product page.
Make sure that we talk about version for NI Kontakt and not classic sf2.

Selling of our products is done only via the Internet. After filling in all the required fields and purchase, in the next 24 hours (usually much less), you will get a link with instructions for download the purchased product on the email address you entered when purchasing. If you have any problem during purchase or downloading of the purchased product(s), please be free to contact us to info@virtual-acoustic.com (contact form at our website), or to email that you got download link from. We will do all to help you get it.

 Unfortunately no because we do not have show room and selling is only via the Internet.

The prices of our products are as they are and we know the best how much time, effort, knowledge and financial resources we invested in this project. If you believe that prices are too high for you, then simply find at other manufacturers what more suited to your needs and abilities. Thank you for your understanding.

Yes. We currently have a bundle of our three first Guerrini accordion models. By purchasing this bundle you get three great accordion at a very reasonable price.

NI Kontakt samples can only be used in NI Kontakt version 5.02 or higher, where the free Kontakt Player is not supported. Except NI Kontakt full version software, it is desirable to have an sound card with low latency to get you greater fidelity and low latency. SF2 samples, which are fully convertible, you can use in your favorite sampler.
For more information, please read the user manual of each product.

Our products are not a library but the classic samples for NI Kontakt. Kontakt libraries are licensed by Native Instruments and can not be legally made without collaboration with Native Instruments. For more information, read the owner's manual for the product that you are interested for.

This question refers to sf2 sample format and exclusively depends on the device you have. If you have a device that accepts samples, then you will probably be able to use our products, but, at first, it is certainly necessary to read the specifications of your device as well as of our product you want to use.

You can practically use any eletronic instrument (keyboard, virtual accordion, guitar etc.) that has MIDI OUT.
Note that Roland virtual accordions have a different mapping system in the left hand (bass keys) so controll of bass will not work as it shold. Right hand (treble tones) will work normal.

Unfortunately it is not possible that there are demo versions of our products because they are samples and not the software. Before you decide to buy, you have the option to read the description on the product page, read user manual and to listen and look at the audio/video demo.