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Because the IPA-140's circuitry isn't balanced, Enrico strongly recommends against using his convenience XLR which insert a summing INA134 op-amp. With inputs 2 and 3 convertible—one as output, one as main-in to bypass the preamp section—the most direct jumper-free input is 4. I duly configured input 3 to 'direct' to add my Nagra Jazz preamp; and input 2 as output to feed my Zu Submission subwoofer. In integrated mode I naturally used input 4. Which finally segues into sonics. I used the IPA-140 with three different speakers, the German Physiks HRS-120 sealed two-way omni with 240Hz-23kHz bending-wave widebander augmented by a 10" downfiring woofer; the big AudioSolutions Rhapsody 200 twin-ported 5-driver 3-way tower; and Sven Boenicke's sealed opposed-sidefiring 10-inch B10 2-way with paralleled mid/tweeters.

Comparator amps included Resolution Audio's C50, Goldmund's Job 225, Roksan's Oxygene integrated and Bakoon's AMP-11R. Alternate sources were Resolution Audio's Cantata and Metrum's Hex. If this number of ancillaries suggests unusual incertitude or a quite comprehensive chase for most suitable partner, you'd be correct. That's because the IPA-140 didn't sound like I expected from its 2MHz brief vis-à-vis the Job and Bakoon. Those are quick, incisive and lit up across their entire bandwidth. They're not drill sergeants but do drill down into the molecules for what I call lucid or crystalline mode without getting crisp or static. Here the Norma played it less lucid. It wasn't as teased out and on insight—being able to penetrate the musical weave and sort out interlocking overlaying patterns—less astute. It was a more amplified wall-of-sound presentation, not a lean 'n' mean unplugged acoustic affair. It begged for a suitably compensatory speaker.

In rather short order this eliminated my Lithuanian towers and my compact German hexagonalists. Why? They both turned too indistinct. Swimmy. The former was due to its underdamped bassiness which needs ultimate control to fall in line. Here the DC-coupled $1.495 Job 225 clearly bested the Norma. The latter was due to starting out less distinct by being full-range omnis. Such dispersion deliberately activates a room's ambient field to create a dominance of reflections over direct sound. It's a quite magical recipe for superior tone and utter soundstage freedom. It's not conducive to overly dense thick amps however. Whilst the ceramic/metal-driver'd Albedo Audio two-way Aptica due for review likely would have been quite ideal, it hadn't arrived yet. What to do? Go upstairs.


This led to my Swiss slivers from Boenicke Audio. They mimic the Germans in their mostly 4pi dispersion but diverge rather critically by mounting their paralleled flat Tangband tweeters on ultra-narrow fronts for conventionally directional treble. Lither, more illuminated and aerated than the others, these all-wood 'boxes' on their wire-suspended floating footers best accommodated the IPA-140's voicing. Having played the digital source field on hand already, I knew that this dominant quality hinged on the amp, not the matching CDP as DAC. I could replace the latter with the Cantata or Hex and barely affect it though on balance the Dutch champion of timing matched best to feature the most.

Whilst this presentation still veered a bit deeper into wall-of-sound mode than I fancy, it got me closest to the more selective sound from what I had on hand.

Armed with Norma's plastic wand with its very practical two-stage volume control (big buttons for fast motion, small buttons for slow fine-tuning in baby steps), I settled down to take the pulse. As I'd taken note of earlier when the Rhapsody 200 had still been augmented by the ENIGMAcoustics electrostatic super tweeters, the only area where ultra bandwidth expectations correlated with actual delivery was in the treble. It had that 'not there' quality of the Raal ribbon I'm so familiar with from the soundkaos Wave 40 and Aries Cerat Gladius speakers.


'Not there' doesn't signify absence per se. It's being MIA on artifice, limitations, grain or coarseness. It's very much like comparing a traditional silk-dome tweeter with a properly integrated ribbon from Aleksandar Radisavljevic. Only in such a juxtaposition might the fabric dome betray its relative B grade. If from 2MHz bandwidth we expected absentee treble phase shift for purer upper harmonics, I'd sign on the dotted line. If we expected blistering transients, a heightened degree of separation, incisiveness and greased reflexes, I wouldn't by any stretch. Here the Bakoon followed by the Job 225 were the more agile trimmer slimmer fighters in the welterweight division which moved like butterfly and stung like bee. The Norma approached a heavyweight.

Polish contributor Wojciech Pacuła likes to classify sound by resolution and selectivity. I consider the two interrelated. I couldn't conceive of high resolution with low selectivity whilst still referring to resolution as high. He does so routinely and vice versa. In either case selectivity is a good term to address where I found the IPA-140 weaker. It refers to separation as the ability to keep simultaneous elements distinctive; to clearly delineate individual layers; and with our focus of attention allow us to quite literally select and leech onto the smallest most subdued line/voice to follow it clearly like an intriguing but whispered conversation two tables over in a crowded restaurant.


Implicitly selectivity is about selection too. You must have something to be selective about. If your local grocer only offers one brand of yogurt across four flavors, even his brightest lights reduce your selectivity compared to the cooperative with ten brands of yogurts across 20+ flavors. That's how selectivity and resolution are always two sides of a coin. With the Norma in the loop I plainly had fewer things to be selective about. This was a more homogeneous of-a-piece read with lowered specificity, less sculpted relief and less delineated layering.

Simultaneously the level of zip, energy and impulsiveness stepped down. This particularly affected intelligibility at lower levels. The powerful and beefy Norma wanted to be played louder before the curtains parted. Perhaps the smaller IPA-70 would have suited me better? After I'd determined that driving the IPA-140 direct from my Nagra Jazz did invigorate and accelerate the presentation, I looked for alternatives. A €12.100 preamp was clearly overkill in this context. As luck would have it, Audio Music's £4.250 valve pre with transformer volume controls was on hand. Though it still begged the question why buy an integrated when you want to use a separate preamp, it did reiterate that for an obvious price Norma's output stage was capable of more subjective speed and separation than its own linestage wrought from it.

Time to interview the Revo DS-1.