Yes the SF2 files are the original ones !
64Mb of samples in this virtuoso box

You can see some of the secrets the bigs are using, like using sample rate between 24000 and 37000 Hz

The problem with the conversion to Yamahan is that when a sample is using by many sound presets, they are duplicated in the Yamaha. I don't know if many motif sounds can share the same audio sample

But that's not the reason here. You are referring to duplicate waveforms in the flash board (which are avoidable, the Motif/MoXF can use the same waveform for multiple voices, you just have to take care yourself that you don't copy duplicates onto the flash if you load several voices one by one). But here the E-MU package already has hundreds of MB when opening it in .x3v-format in the Melas waveform editor on PC. The waveform editor doesn't duplicate any samples, obviously it is the .x3 format itself which inflates the data size.

Yes this is the reason ;à

If you sort the wav samples by size, you will see that the same sample is duplicated many times for each instrument it is used inside.

Maybe the x3 format does not allow to use the same sample inside many different instruments, so they simply duplicate them

Sorry, then I understood you wrongly. I thought you were talking about duplicated waveforms, but you are referring to duplicated individual samples as components of a waveform. So that's the explanation then, thanks. Maybe this occurs with other libraries too, that's why they are so "large"...

Something is still wrong, the voices are not correctly connected to waveforms, they are mute and refer to Yamaha factory waveforms now, but I can install the EMU waveforms on the flash, which is the most important, so I can form voices by selecting the new waveforms manually.

Besides the marcato strings, I now have gorgeous small strings and symphonic big strings - better ones than Garritan!! I also have the best French Horns now. It's so remarkable that I have to repeat it: 15-year-old EMU samples have significantly, almost dramatically upgraded the orchestral voices of my MoXF.

Demo of three strings voices and French Horns, exclusively using E-MU Virtuoso samples!
https://soundcloud.com/rorosetree/e-mu-virtuoso-strings-fyamaha-motifmoxf

So, how do YOU rate them compared to the Garritan, DSF Strings, SRX-04/06 and SuperNatural?

I rate them to be on the same high level as the other ones mentioned! DSF strings have longer samples and still a higher quality for the 5-piece sections, but they neither include a really big section nor a real marcato version. So the E-MU strings indeed contribute high-quality variations I haven't had in the MoXF so far. The Garritan big strings have some features I don't always like: they sound odd in the low keys and have quite a strong vibrato in the upper keys. Maybe SRX-04 and supernatural strings combined do a similar job, but it's always good to have various different high-quality strings to combine them!

Thanks for your review! When it comes to Strings, the more the merrier!

To complete the picture about the E-MU Virtuoso: as good as the orchestral strings are, especially for their age, as bad are the brass sounds. This is really its weakness except French Horn. Trumpets, trombones and brass sections as a whole are far below the standard of the old Roland Orchestral boards and SRX 06.
Woodwinds are quite good except flutes, where I miss sampled vibrato. Solo strings are quite good.

Thanks for the details.