When too little is too small

Reviewer: Srajan Ebaen
Financial interests: click here
Main system: Sources: Retina 5K 27" iMac (i5, 256GB SSD, 40GB RAM, Sonoma 14), 4TB external SSD with Thunderbolt 3, Audirvana Studio, Qobuz Sublime, Singxer SU-6 USB bridge, LHY Audio SW-8 & SW-6 switch, Sonnet Pasithea, LAiV Audio Harmony; Active filter: spl Audio Crossover MkII; Power amplifiers: Vinshine/Kinki Dazzle & mono Ncore 500 Nord Acoustic amps on subwoofer; Headamp: Enleum AMP-23R; Phones: Raal 1995 Immanis; Loudspeakers: Qualio IQ [on loan] Cables: Exact Express Flame, Furutech; Power delivery: 2 x Kinki/Vinshine Tai Hang on amps and source stack, Furutech DPS-4.1 between wall and conditioners; Equipment rack: Artesanía Audio Exoteryc double-wide 3-tier with optional glass shelves, Exoteryc amp stands; Sundry accessories: Acoustic System resonators, AudioQuest FogLifters; Room: 6 x 8m with open door behind listening seat; Room treatment: 2 x PSI Audio AVAA C214 active bass traps
2nd system: Source: FiiO R7 into Soundaware D300Ref SD transport to Cen.Grand DSDAC 1.0 Deluxe with POW; Preamp/filter: Lifesaver Audio Gradient Box 2; Amplifier: Kinki Studio EX-B7 monos; Loudspeakers: ModalAkustik MusikBoxx; Subwoofer: Zu Method; Cable loom: Exact Express Earth; Power delivery: Vibex Granada/Alhambra, Akiko Audio Corelli Corundum & Castello Solo; Equipment rack: Hifistay Mythology Transform X-Frame [on extended loan]; Sundry accessories: Furutech cable lifts, Furutech NFC Clear Lines; Room: ~3.5 x 8m
2nd headfi system: DAC: Cen.Grand DSDAC 1.0 Deluxe with POW; Headamp: Cen.Grand Silver Fox; Headphones: Raal 1995 Magna, HifiMan Susvara
Desktop system: Source: HP Z2 workstation Win11/64; USB bridge: LHY UIP; Ethernet bridge: LHY EFI; Ethernet reclocker: Stack SmoothLAN; DACs: Audalytic DR701 & Gustard R26II; Headphone/preamp: FangSound Dionysus; Speaker amps: Topping B200 monos; Loudspeakers: Virtual Hifi Viper; Headphones: Final D-8000, aune SR7000, FiiO FT7
Upstairs headfi system: FiiO R7; Headphones: Meze 109 Pro, Fiio FT3
2nd upstairs speaker system: Source: FiiO R7; DAC/pre: COS D1; Amplifier: Kinki EX-M7; Loudspeakers: sound|kaos Vox3 with Dynaudio S18 subwoofer
2-channel video system: Source: Oppo BDP-105; All-in-One: Gold Note IS-1000 Deluxe; Loudspeakers: Zu Mission; Subwoofer: Zu Mission; Power delivery: Furutech eTP-8, Room: ~6x4m

Today follows up an earlier question; about when too small is too little. As suggested in the prior editorial, a 5¼" 2-way strikes me as the ideal monitor choice in a stereo 2.1/2.2 context though on occasion, a 4" version can do the job. What that piece didn't get into was the where of the job. In my above nearfield bonsai system, the speakers are MonAcoustic minis. Their isobaric pairs of 4-inch MarkAudio Alpair spiderless widebanders hand off at 15kHz to a micro AMT very similar to Norbert Lindemann's Move/Move Mini. The ported alignment in an aluminium cab makes these good for ~65Hz bass extension. If we use our sub in basic augmentation mode and want a linear progression, we're forced to mirror-image the speaker's F3 with the sub's symmetrical entry. Anything lower and we cause a hole. Anything higher and we create a paunch from undue overlap. Today's question is simply this. Is asking a 4-inch light cone playing well into the mid treble to also reach into the mid bass ideal? If we already have a heavier high-stroke 9½" active woofer at our disposal like this system has doubled up in its Dynaudio 18S, what about bringing it in at ~100Hz for example? Wouldn't that critical area benefit from more cone surface and displacement?

Shanling EM7 SD card server/DAC ⇒ Lifesaver Audio Gradient Box active crossover with remote volume spl ⇒ LAiV Audio Crescendo Chorus monos

The only way we can properly experiment with alternate handover frequencies is to also high-pass our mains. With a 120Hz/4th-order entry for our sub, we can't run these minis wide open down to 65Hz -3dB and not cause a bulge from undue overlap. Meanwhile an analog active crossover here represented by Lifesaver Audio's Gradient Box can maintain symmetrical handovers at all frequencies above the monitors' limit to guarantee a linear response with the correct sub attenuator setting. This goes beyond the well-known advantages of removing LF from the monitor voice coils which reduces their stroke requirements and concomitant distortion potential. Now we get to explore the precise point where too small does become too little. Our ears can tell us whether our de facto 9.5" 2½-way speakers best cross at 65Hz, 120Hz or anywhere between for best in-room blend and dynamic contrast. It's this option which often fails consideration when deciding between augmentation and filter mode during any subwoofer addition. Augmentation mode is inherently limited to tacking on the sub where the mains fade. Hi/lo-pass filter mode expands our dovetailing options. If we use two subs to avoid mono limitations above 100Hz, these dovetailing options can cover many additional higher frequencies well past 160Hz. Either way, having more choices to trim our sonics to a particular application is always more advantageous than fewer options. In this instance the missing link is an active analog crossover, an admitted rarity in our sector. I run units from Lifesaver Audio and spl and in my hifi closet still have a Sublime Acoustics box. The digital domain opens more options and can potentially reduce the box count. Either way, the point is added flexibility about where to set our sub/sat system's lower crossover point. In my sample system, the best performance comes from a 120Hz transition as the highest this crossover provides. Destressed from LF they couldn't handle, the overachieving lilac munchkins play more open and expressive. Exploiting the sub's greater artillery higher up gives the system more punch and gravitas. The takeaway? 4 inches for 65Hz is too small. Shifting that up by an octave is a win/win. What's more, should room or speakers change, the same flexibility will adapt perfectly; again. That's enough self gratification for one day…