iFi Releases Firmware 5.30C for XMOS-based Products

Back in March iFi released a firmware update for it’s XMOS-based devices which enabled MQA support along with various code optimisations. Now, it seems, iFi had still been hard at work since then and have released firmware version 5.30C which goes to further improve their products.

What’s Firmware 5.30C All About?

It retains the MQA support introduced with firmware 5.30, but the most important addition (or rather change) with the firmware is that we’re now getting the Gibbs Transient Optimised Digital (GTO) Filter which was first seen on iFi’s Pro iDSD. As the actual filter selection on iFi’s devices is done with physical switches, in order to implement this new filter it means that another filter had to bite the dust. As a result, the GTO filter introduced with firmware 5.30C replaces the Minimum Phase filter.
So, what’s all this fuss about filters? Well, these digital filters influence (among other things) the transient response of impulses. When the DAC device has to deal with an impulse (all music is just a long series of rapid impulses) there is an inevitable pre- and post-ringing that takes place. Basically it’s a bunch of duplicates of the original impulse that occur before and after the original impulse, but they are usually much smaller (lower volume) than the original impulse signal. So, what does this matter to you? Well, those pre- and post-rings can be thought of as adding reverb (or echo) to the music. To some extent a certain amount of reverb can be desirable as it tends to give you the illusion of a bigger “stage”. In the same way that, if you clap your hands in a small empty room versus clapping your hands in a large concert hall, the resulting echos you hear is the information that your brain uses to decode the size of the room (other than you actually seeing it, of course). But in the case of listening to music, you have no visual cues to determine the size of the performance setting, and so your brain will use audio cues (in this case the “echos” produced by the pre- and post-ringing) to figure out what’s going on.
What this means is that, if there’s too much pre- and post-ringing, then not only is your brain lead to believe that the “stage” might be bigger than what it actually is, but more important is the fact that the resultant pre- and post-ringing of one impulse will interfere with both adjacent impulses as well as their resultant ringing.
Thus, by reducing pre- and post-ringing artefacts, the original impulse is kept in tact. In the real world, this translates to better instrument separation.

OK, that explanation took a bit longer than I had intended, but if you’d like to get more in-depth info then head over to this document written by iFi.

 

Get The Update

You can obtain the relevant firmware 5.30C file from this page on iFi’s site

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