Slowly but surely, I think that I am converging toward a design that I really, really like. Clearly, stepping out of Eurorack’s constraints has been quite liberating. Today, I really wish that I could have an ISHIZENO i8 to play with. Here are the changes that we made to it, form top to bottom:
First, on the advice of our mentor, we’ve added one LED per CV port, green for inputs and red for outputs. I’m not exactly sure what piece of silicon will drive these, but we have several good options.
Second, we’ve moved our two XLR outputs between the two pairs of DB25 connectors. This will make it easier to develop two separate printed circuit boards for our audio interface, one for ADC and one for DAC. This is due to the fact that our ADC board will need to host 8 ES9102 converters with buffers, while the DAC board will just need 2 ES9018 chips. As a result, the ADC board will be much larger than the DAC board, which requires careful planning.
Third, I’ve added one blue LED per channel in order to indicate that a channel’s Parallella board is working properly. Internally, I’m also working on a new routing scheme for our audio and CV signals that will distribute load across all 8 Parallella boards. More details on this over the week-end.
Fourth, as expected, I’ve added two new buttons per channel, one for selection (Sel), and one for recording (Rec). These buttons are LED illuminated and have been put around the Mute button, using three different colors (Green, Yellow, Red).
Fifth, the five dynamically-assigned buttons (A, B, C, D, E) are black instead of white in order to better separate the upper part of the faceplate from its lower part. This is mostly for cosmetic reasons, but it might have an impact on the touch-and-feel of the interface, since black buttons will be hard, while white ones will be soft.
Sixth, I have removed one SD Card slot from the frontplate, leaving just one. Putting two was overkill in the first place, and would have added a lot of complexity that we clearly do not need.
I am now working on a revised block diagram, with a clear outline of all the printed circuit boards that we will need to develop. At last count, we have 7 of them, which is a bit scary. By the same token, it will make the system quite modular.
Did I say I really, really want one?