Step 4. To circle the wagon, I heard the Source II on the Move/Groove stack…

… then my domestic 2.1 set. With the menu unavailable without Internet and app, by default the Source II resamples all PCM to DSD 256. My iFi Audio iDSD Pro Signature can resample to 1'024 but I prefer its upsampled PCM mode. My Cen.Grand DSDAC 1.0 Deluxe resamples all to DSD 256, 512 or 1'024. Its implementation only competes with PCM resolution and treble clarity at 512 or better. Hence my default is 1'024. Lindemann's music:book implementation championed DSD's softer more billowy textures with less separation and articulation in the depth domain, a slightly polite treble and reverb-enhanced spatiality.

From my kit and no Groove to Norbert's class D power then DSD became a multi-stage progression into a mellower weightier warmer milieu. To make Move most similar to my domestic system required my own kit. The full-bore Lindemann set shifted emphasis from forward-leaning transients into more relaxed bloom. A resolution/energy-first tuning added body and tone. Against the theme of old dog new tricks I had the expected preference. Moving this show downstairs into the main 6x8m room ran my usual €2'700 Laiv Audio Harmony coupled to a Lifesaver Audio icOn 4 autoformer passive to add precision analog volume control. To eliminate sub 160Hz room interference, I turned on my new set of PSI Audio AVAA 214C active bass traps.

Step 4½. Here my familiar sonic profile includes hybrid mains from Qualio Audio whose Satori papyrus 6" widebander and Mundorf AMT operate dipole. At 100Hz/4th-order I actively cross them to a dual 15" 'super-dipole' so cardioid sub from sound|kaos. Across its 2½-octave bandwidth, that eliminates side-wall reflections and attenuates front-wall reflections. Its burly Audio Technology cellulose woofers face each other across a narrow slot in extreme proximity. Their rear waves encounter immediate curved walls before exiting counter phase with the front slot for strategic radiation shaping. This 25Hz bass is exceptionally well damped. Functionally it doesn't work as a common pressure generator but rare velocity converter. It's a virtually impossible act for conventional box bass to follow which won't express the same speed and control nor definition of pitch or texture. It'll exhibit inferior stoppage. At €8'700 in a stacked Ply folded open baffle sans electronics or filter, adding those elements externally prices my solution wildly beyond the Groove. Just so, whilst I still had that bass reference in my inner ear, inevitable critique was predestined.

I obviously can't break down Groove's compound effect. Contributors certainly included sidewall reflections which our Ripole sub cancels so effectively. They likely included some box talk of internal reflections leaking through the woofer diaphragm; possibly passive radiator lag; and generally lower driver damping. Whilst the Groove's amplitude integrated ideally with the Move and extension lacked for little, the in-room time domain across its bandwidth was sloppier. Thinking readers appreciate that I just described Box Bass 101. It's what happens whenever wave lengths longer than enclosure dimensions wrap around a box to propagate in omni fashion. That energy plays acoustic snookers with our hard room boundaries before it hits our ears lagging behind the direct sound. Most listeners are inured to this effect because it's so common. It's headfi fans who recognize the difference and already identified Move's headfi-reminiscent immediacy. That's because open-backed headphones don't see a room. Their bandwidth doesn't suffer a belt line above which sounds decay as recorded whilst below it they decay as a room dictates. Their bandwidth is texturally rather more continuous. Precisely because of the Alpair 5's point-source reflexes and purity, Groove's unavoidable intrusion across the room's resonant sub 150Hz zone exerted greater contrast. Move being rather better above the belt line caused stronger textural discontinuity against Groove below behaving perfectly conventional so coloured by the room. Though my active bass traps subtracted the front wall and its corners from the equation—without them my 35/70Hz room modes boomed—the other boundaries remained in play and with them, the smaller lateral room mode. My ear/brain had to reset to this behaviour before I could stop getting hung up by it. Don't read this as anything other than more Captain Obvious. It's not particular to this Lindemann stack. It's common to all box bass without a true infinite baffle.