They are each unique in some ways and the same in many ways.

I believe (although some beg to differ) the processing is nearly the same betweem 568.2mm (especially with beta 2.5), G68 and 861v4 (right down to the flaws).

861v4 allows customization and Meridian's best DACs. G68 and 568 do not.

For DSP Speakers I find no difference but others do (perhaps with younger, better trained ears do).

The biggested difference in 568.2mm is not enough MIPS to run MRC. But otherwise very similar.

- Fiddler (IMHO)

If you think listening to music is fun, try learning an instrument.
HT: G61RSL, 4x5K, 5.5KHC, 2xSC6000, Transporter, HD621, Philips BDP7501 4K, Tivo, 65" LG OLED 4K C6
Computer: Foobar2000, 5K, Mojo, HiFiMan HE1000 V2