The Reference Series units in this video offer balanced power. Note the difference in the size of the transformer as compared to the Elite series units, that's due to balanced power. The P-2400 weighs 90lbs. The consumer level IT Reference 20i offers balanced power and is twice the price of the P-2400-IT which is studio grade. I can't answer why but it seems to me that makes the P-2400 a great buy.
https://www.youtube.com/watch?v=zONGh3UMhXs
and here is more information from Garth Powell from Furman....
https://www.youtube.com/watch?v=SAAEhtAUT34
https://www.youtube.com/watch?v=zONGh3UMhXs
and here is more information from Garth Powell from Furman....
https://www.youtube.com/watch?v=SAAEhtAUT34