Firmware has always had a small but fundamental impact on musicality. It was evident already with CD players. Remember the Unidisk firmware upgrades that were done by inserting a disc? Each and every one of those firmwares sounded a little different, even though some of the changes had nothing to do with the musical signal.
Much later I ran into it with Kikkin and Sagatun. There was a memory function planned for Sagatun, so that if you switched it off, it would return to the same volume and input upon startup. I also wanted to add a volume offset, so that for instance volume would always increase 8 steps when choosing input 2 and then drop 8 steps when leaving input 2. But it turned out that the memory in Sagatun needed to be empty. Inserting just a few numbers into the otherwise blank memory caused a very slight but annoying sense of detachment in the music. Electronically I could not understand it at all. But it was so easily reproduced and heard that the only possible decision was to scrap all ideas related to memory. It had to remain blank.
That the firmware in a digital music streamer affects its sound quality is probably easier to accept than the Sagatun example. After all, the streamer is assembling bits and converting them to music, so unlike the analogue preamp, it's digital in its very essence.
In practice, however, there are some effects of firmware that are quite mysterious. Every manufacturer of high quality streamers know this, but they don't want to talk about it. The common policy is to deny it, completely and always. This is understandable, because if you admit that your firmware update - one that contains only some insignificant bug fixes - actually makes your streamer sound a little different, you will have trouble on your hands. Because then you will have to start listening to every change you make. And you will need to decide whether the musical effect was for the better or for the worse. And if worse, by how much? Is the bug fix really worth that degradation of musicality? Maybe you can fix the bug in a different way and leave the music unaffected? In short: Working with firmware will be much, much harder. You will never know in advance how much effort any task is going to require.
Having followed the 'which streamer firmware is the best?' discussions on various forums, we decided right from the start that we'd do it differently with Källa. We chose the hard way, because it's more honest, more rewarding, better for owners and frankly, we felt that in order to make the very best digital music streamer, we have to keep everything optimized. There wasn't really any choice.
