Hydra 6 vs Hydra 8?

If I only need 6 outlets is the Hydra 6 as good as the Hydra 8? Whats the sonic difference?
If I remember correctly there is a review on www.stereotimes.com about the hydras. I think ( not positive ) it was mentioned that the makup of the 8 Hydra is a bit different then the others ,sound and internal make up. From what i can remember the 8 was the best ,as far as bass weight and authority....due to the beefier power supply. Not sure if that helps at all,,,,
Beefier power supply? I thought Hydra's were passive devices and dont use power supplies? Of course I could be wrong. I believe the 8 has the Fesi-1000 compound in it and the 6 doesnt. I have seen in reviews that the sound is a bit different between the two; the 6 sounding more crisp and digital and the 8 sounding a bit more ananlog. Again I could be wrong. Either way I feel you cant go wrong.
That's a good question considering the Hydra 8 retails for $1995.00 and the Hydra 6 at $995.00. You can buy two Hydra 6's for the price of one Hydra 8. I also would like to know what the sonic differences are between the two.