To help answer all the questions we’re getting regarding the next free software update and the Altitude +4 channel upgrade, here is the latest information.
As you know, the plan for the Altitude16 was to use the Toslink output to feed 4 channels at up to 96K to an external ADAT format D/A converter.
However, as our R&D team was in the process of evaluating available ADAT converters, they came up with an alternate approach that we believe will be a better solution for everyone. Instead of sending the four additional channels in the ADAT format, the AL16 will feed four channels in two conventional S/PDIF stereo pairs of PCM. Two channels will be on the coaxial digital output and two channels will be on the Toslink output. This will enable the user to use any external DAC with 96KHz capability.
In part, this change was the result of our qualifying various ADAT converters and discovering that most of them do not handle sample rate changes as one would have imagined. Some of them required the user to manually change the sample rate, while others could sometimes generate a burst of full-scale digital noise during the “automatic” change. Neither was acceptable from a user perspective.
By comparison, using the two S/PDIF outputs (both optical and coaxial electrical) opens a wide world of stereo DACs in a price range that will suit pretty much any budget.
We apologize for the delay, but we feel that this decision is in everyone’s best interest. It will make adding some extra channels to your Altitude16 much easier, and it is also more consistent with the same software update for the Altitude32 (which uses four of the available multichannel AES/EBU channels on the DB25 connector).