Larry explained that when you buy a select you buy into a ten year renewal program where for the first year all upgrades and improvements are free of charge and then for the subsequent 9 years are sold at trade price. For next year there will be a still more costly two box select DAC and current purchasers may trade in for it at no charge.
The current select could be regarded as a fully loaded MSB Diamond DAC plus one major and undisclosed improvement. Larry related that years of development had gone into two aspects or design vectors as he termed them, namely processor accuracy, and jitter. However recent work on their master prototype, dubbed Edison, revealed that there was a third vector, up till now not properly explored, and that when developed and applied to the Diamond DAC IV resulted in such a performance leap that it resulted in the select.
(http://www.msbtech.com/products/dac4select.php?Page=../index)
Martin Colloms