As this video begins to unpack, combining the functionality of five big IC into one has Serce benefit manufacturing ease and shorter signal paths without redundant signal routing/reflections from chip to chip. DSP no longer interferes, even its power consumption reduced whilst allowing Ferrum to implement digital filters beyond the stock ESS options for superior stopband attenuation, upsampling algorithms, interpolation and I/V conversion. Ferrum are particularly proud of their current-to-voltage converter. It undermines myopia that converter silicon cements sonics; or that only the analog output stage and power supply matter. As Ferrum explain, how one pre-conditions digital signal before it hits a converter chip is very important. Think proprietary DSP including custom filters and upsamplers superior to what D/A chip makers embed. It's how Ferrum claim that their Sabre implementation sounds very different from all others known so far.
What Ferrum's YT channel also shows is how young many members of its engineering team are. This isn't the old guard but young turks who look at things in new ways. When I asked their boss more details, he was on his return flight from the Guangzhou show and would soon take off for Axpona. There's more to audio engineering than audio engineering. Proselytising at international trade shows is an important yet time-consuming part of considerable expense. Back on Wandla, the display can auto-adjust its brightness to surrounding conditions with a selectable ambient light sensor. There's settable display-off timing. Info shows the installed software version where ongoing updates are expected to bolt on new features. During levels changes the numerical volume values increase size to be easier read from the seat. The display also shows current sample rate, bit depth and file format as well as MQA unfold status via colored LED.
The analog volume is a Muses PGA with digitally triggered analog resistor ladders in dual mono buffered by "opamps whose careful selection proved crucial for best sonics." Initial I²S configuration is in PS Audio mode. "As demands arise, we'll add more configs in a manner similar to Hypsos." About output stage bias, "that's a bit complicated. Theoretically it's A/B. But when the load is modest, in most cases it won't leave class A. And we did experiment with forcing Wandla's output stage deeper into A class bias but sonics disappointed. In the end I'd like to draw attention to the ESS chip's output, namely our current-to-voltage circuit. It's a proprietary development: composite, ultra fast, of ultra-low distortion and most vitally, it sounds as good as it measures."
As to MQA, by April 2023 they had declared insolvency whilst streaming service Tidal announced that they'd be shortly offering standard .flac files sans MQA in their hi-rez tier with no intention to acquire MQA's assets. Wandla won't care because MQA is aboard yet their lossy algorithm fully bypassed for all non-MQA materials. So Wandla remains codec agnostic. If you own a large MQA library, that won't suddenly evaporate should MQA the company fold. Wandla can play such files as that codec intended. If you don't own a single MQA file, it's no issue either. With PCM support up to 32/768 and DSD up to 256, no native file is left behind. Being able to choose between digital/analog volume or none is one more expression of letting the client decide. Likewise for Ferrum's DDF aka dynamic digital filtering library which will still grow; and promise to add I²S pin configs as owners of transports incompatible with the initial PS Audio mode report in.
By May 30th so past the Munich show, my Wandla/Hypsos loaners were air-bound. Ferrum were clearly keen that I judge their latest with upgraded power supply. From prior Hypsos meets I knew how to exploit its 'sweet spot' tuning. Within a component's safe parameters one either increases voltage for lower wattage (the sound gets darker, heavier and softer) or does the inverse (the sound gets quicker, leaner and more articulate). It's not a one-value-fits-all deal. Wandla's acceptable power voltages span from 22-30V. That invites personal trials to mean trusting our ears. It's weirdly where many draw the line afraid that their hearing will cheat them. Of the truth? Perception is truth when our nervous system plays inevitable filter. Do we take a breathalyzer test to measure how deeply in love we've fallen lest our imagination trick us? Do we keep swallowing food that's too salty because its cook insists that it's not? Audio is no different. Our perception rules. All the rest is window dressing, small print or sheer noise.
Amidst the incessant noise of the MOC's ground floor, ferrum exhibited with Meze planarmagnetic and Raal-Requisite true ribbon headfi in their open booth with multiple stacks of Wandla, Oor & Hypsos. Two weeks later Wandla had its first award from Poland's HighFidelty.pl. A week later I could make up my own mind. First testbed was my revised office desktop. There a Singxer SU-6 USB bridge intercedes between Win 10/64 work station with Audirvana Studio/Qobuz Sublime and DAC. The latter feeds an Enleum AMP-23 amp into EnigmAcoustics M1 monitor; or HifiMan Susvara headphones. Being nearfield or top-shelf headfi, it's high res either way so perfect to chase the sonic crumbs of digital filters¹.
¹ Of ESS's seven stock filters embedded on their chip, Wandla makes accessible three. Those are linear phase fast roll-off; minimum phase fast roll-off for no pre-ringing; and apodizing for lower pre/post ringing with less extreme aliasing rejection. The first two HQ filters from Signalyst's Jussi Laako are more apodizers called Gauss and Apodizing. Gauss focuses on "optimal time/frequency response", the other on "recordings made in real acoustics or which otherwise have notable spatial information". By subscribing to Wandla's online survey, users can vote on their least/most favorite filters and propose others not currently loaded. Over time Ferrum hope to have loaded the most popular/effective options through this new form of intellectual crowd sourcing. Subscribers will be contacted with new firmware patches whenever the filter library changes. This type interaction is also common with crowdfunded micro brands in the watch industry. Sundry 3D renders of different cases, color ways, hands and straps are put up for vote before the most popular ones go into production.