Some additional info regarding the new updated C1/D1 HD boards and HD link from CH.
“The upgrade is simple to perform. The HD boards replace the current ones. The HD boards fit inside the unit in the slot previously used by the current boards. A firmware update has to be performed to enable the HD boards (firmware on our website). The old boards can be discarded and you don't need to send them back. The old boards don't work with the new piece of firmware and therefore they won't appear in the menus. In other words, you cannot have both the HD and the old board in the same unit. Please note that if both units are inadvertently fitted together in a unit, nothing bad will happen, no board nor the unit will suffer any hardware damage.
The ordering process goes through your dealer, but you can then opt for the dealer to install the board or you can install it yourself. To be on the safe side, I however always recommend you to ask an authorized dealer to perform the update.
The HD boards provide more processing power and is to be seen as a platform for enabling new features. The CH Link HD is the new CH Link between D1 and C1. The transmission mechanism is further improved. Besides, The C1 HD board (DIG_IN_HD) allows a new filter to be implemented, filter that replaces all the previous filters for PCM and DSD (linear phase, minimal phase, etc). This filter is much more complex and resource hungry than the ones it replaces. it is a filter post up-sampler allowing the audio data to be better presented to the converter chips, improving the conversion process.
Thanks to the HD boards and its processing power, future software features can be added simply by software updates.
Please note that no new development will be made to the current C1 DIG In and D1 Dig Out boards.
The cost for the C1 DIG_IN_HD board is $2'500. The cost for the D1 DIG_OUT_HD board is also $2'500. A 1-meter CH Link HD cable costs $2’000.
A product update policy is in place for C1 and D1 units purchased in 2017 and after:
C1: 50% off MSRP (DIG_IN HD)
D1: update free of charge (DIG_OUT_HD)
C1 Mono: all the C1 Mono units ever produced receive the HD upgrade free of charge (DIG_IN_HD). Besides, ordering the C1 to C1 Mono upgrade automatically includes the upgrade to HD board(s) at no cost.
Please note that all the I1 integrated amplifiers will be fitted with the DIG_IN_HD board.”
Hope this helps.
Chris