Equality revisited. I now ran double power over the Job 225. Likely far more meaningful, I had far beefier true dual-mono power supplies so one mains toroid per 15" woofer. That must have been cause for my célébre because like a retuned drum skin that had lost tension or a softly sprung trampoline we retighten, my low end had new pep in its step. More tautness and bounce. That impacted musical momentum and alacrity. My engine room of rhythmic bass makers ran in lower gear so at higher RPM. Our perception of musical vitality links directly to upper bass pertness and kick. The more punctual it cracks and tickles, the more awake and astute our system's pace, rhythm and timing respond. My apparent enabler was heightened driver control; and greater headroom for momentary voltage swings. Presumed room-talk remnants had cancelled. This paralleled how when mechanical isolators cut structural gain, certain apparent room-acoustic issues turn out to have been caused elsewhere. After all, my room hadn't changed nor had anything other than the bass amp. Yet minor spots of looseness had firmed up further to strip more resonant fat.

To be sure, this had absolutely nothing to do with bass getting louder or mightier¹. This was all about greater intelligibility from superior punctuality or diction. It made for a closer approximation of equality between upper and lower bands. As my mental judge traverses the audible bandwidth, he hopes to spot no textural difference, just one seamless continuity regardless of pitch or loudness. That's been my ongoing pursuit ever since I set out on active bass via a stereo 2.1 work-load split. What kicked that off was hearing the phenomenal speed and absence of energy storage of Raal-Requisite's SR1a true-ribbon earspeakers. That's what I wanted my speaker system to do as well. It's been quite the journey. Qualio's hybrid open-baffle IQ speakers were one key discovery. Martin Gateley's cardioid sound|kaos sub was another. Tying the lot together required a flexible active analogue precision crossover. Lifesaver Audio in the UK's Manchester built one with some wish-list input from yours truly called the Gradient Box. Next I had to research actually effective decouplers to prevent vibrational transfer between big sub and floor. From Boenicke to sound|kaos and Wellfloat, the best isolators for that gig all ran wire suspension. Now I must thank one lateral Exicon Mosfet in our yeoman Job 225 amp for dying to overload its remainders with thermal runaway. Without it I'd not have investigated a new bass amp. During the weeks of the Job being down to run our main speakers unfiltered, I really couldn't wait to return to high-passed 2.1 mode. This wasn't about restoring raw bass reach but treble and midrange clarity shining all the way down into the low registers. Once you've heard Ripol bass, anything less becomes obvious patchwork like ponderous murk below, lightning-y lucidity above. I want equal-opportunity lucidity; or as close as my fiscal limits and renter's restrictions can get. On that score, Kinki Studio's direct-coupled class A/B EX-M7 makes for a fabulous sub amplifier. With identical gain/sensitivity specs as the speaker amps, the only compensation necessary is whatever sensitivity offset might exist between speakers and sub. That, setting the filter hinge and controlling the master volume is what Pál's active crossover with remote control is for.
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¹ The worst example of misconceived bass power is the concept of 'room lock' which turns our listening space into an overloaded pressure chamber. That's the very last thing you should want. Just listen to a top pair of headphones which drops that entire erroneous idea to demonstrate what recorded bass without room interference actually sounds like on proper amplitude and correct texture. Better yet, take the Raal ribbons for a test drive across your gnarliest bass terrain. That'll be a real wakeup call!

What about class D's 1-2 punch of iron-fisted mega power? Again, my 4th-order Linkwitz-Riley filter sits at a high 100Hz. That's to extend the sub's directional reflection-cancelling benefits across a good two octaves when its slopes define by their 6dB point at the filter frequency. Set to 40Hz, perhaps class D might work. But I don't fancy it for reaching well into the upper bass. It gets too dry, wiry and lacks elasticity and harmonic development. True, our upstairs Dynaudio S18 sub is class D. There it's not problematic because the filter sits at 60Hz; and a dual-woofer sealed alignment makes for a classic omni radiator. It reflects off all the walls, ceiling and floor. Introducing crispy dryness into said reverberance is ideal and welcome. With more than half the downstairs room's LF resonance cut with a folded open baffle's anti-phase cancellation; and given a Ripol's velocity conversion not pressure-generating MO; class D's excess bass damping becomes unnatural. I much prefer Kinki's class AB implementation. It's juicy and snappy at the same time.

Today then papery promises and ear pleasures converged on a bull's eye. How I read that is as the dragstrip's 'no replacement for displacement' mantra. It holds that momentary current demands from spiky bass transients pull far more power than the mid and high registers ever draw. Doubling my sub power and its power supply paid heed with admittedly unexpected results. No matter how trite, some things are simply true. At the SPL I listen to, would still more power like Cen.Grand's colossal 900-watt monos go further? I'm not about to find out. I'm far too happy with things as they are. Did swapping the monos to bass duty and the stereo amp to speaker drive register? I slightly preferred my original setup —and this could seem contrary logic—particularly at low SPL because recorded ambiance felt still more crystallized. That's not about primary images of instruments and singers. It's about the planktonic aspects of venue space or a strategic mix's artifice in which the images arise; the in-between and around 'n' behind-them stuff. So our monos will stay on the speakers, the stereo amp on the sub. Their employment contracts are signed. Now get ye to work, band of happy Kinkis.