Amplifier standards buzzing around the $2k price point are neatly base-lined (for this reviewer) by the REDGUM RGi60 – a hitherto personal favourite with both Magnepan’s MMG and KEF’s LS50. It’s an integrated that’s scopious, refined, smooth and urbane whilst retaining an ability to deliver on time and under budget when it comes to dynamics (both micro and macro) and tonal colour. There’s a nice balance between connective flesh and structural bone.
The RGi60 is a real all-rounder but driving the entry level Magnepans it runs close to its upper-current-delivery limit; the thermal protection circuit is a must. You certainly wouldn’t want to challenge this REDGUM with any of the badder Maggies, for which you’ll need more than even its larger-than-life 60wpc can deliver. And that delivery’s gonna cost ya…
…or is it. Money = power and power = money. Class D is the pragmatist’s choice when maximizing the power-dollar quotient.
No pre-judice. Anyone who still thinks of Class D as needles and pins or flat and lifeless needs to take a long look at themselves. Such thinking is as dated and cringe worthy as the casual racism that permeated British sitcoms of the 70s. (“Mind Your Language” anyone?).
With Miss Conceptions banished to another era, it’s time for a longer listen to the Wyred4Sound mAmps, mono blocks for the budget-focussed (and green-conscious) audiophile: 255wpc into 8 ohms, 430 wpc into ohms, balanced and single ended inputs, US$1800 /pr.
Each mAMP is built into the same shoebox-type casework as the previously reviewed mINT-egrated but “packs in a 125ASX2 module in BTL configuration rather than the 50ASX2 permanent BTL module in the mINT”, says designer EJ Sarmento.
Just as DACs are not solely defined by their chip choices, so it is with switching amplifiers. The end result can’t be solely attributed to the ICEPower module pulled from the shelf – its the implementation that counts. The magic in Wyred4Sound’s mAMP is a new quad FET input buffer.
In surrendering the all-in-one niceties of the integrated (pre, DAC, headphone stage) for the two-box solution you get a oodles of power. With that comes a MUCH larger soundstage, better separation and a lot more detail. Feed ‘em right and a pair of mAMPs will be a considerable step-up from the mINT.
Bowel feeding. A good number of modern DACs pack in-built volume attenuation allowing the user to (theoretically) skip out on a separate pre-amplification stage. I ran a handful of these DACs direct into Wyred4Sound’s mAMPs. The wildly varying results that follow underscore how revealing these mini monos can be.
I started by establishing a baseline data point – reaaal basic. First DAC unto the breach was the Resonessence Labs Concero HP (CA$850, review here), an all-ine-one DAC/headphone amplifier that utilises the ES9018-2M’s on chip digital volume control. It’s not really intended to be used as a digital pre-amplifier but curiosity got the better of me. CEntrance’s Reserve Series took the 1/4″ output to twin RCA inputs on the mAMPs and the play button went down on Bob Dylan’s “Days Of ’49”, which spilled light-n-bright. However, the harmonica that opened “Early Mornin’ Rain” screeeeeeeeeeeched its way out of the KEF LS50. Nope – no free pre-lunch here.
NOTE! Don’t go thinking this is how the Concero HP plays when driving headphones. Headphones are what it was designed for and so headphones are its forte. See my Concero HP coverage here and here.
The AURALiC Vega (US$3499, review here, here and here) playing source-direct via its digital attenuation circuit is another chapter devoid of a happy ending. (The extra-ordinary) 4v on the Vega’s output(s) and the mAmps’ 1.43v input sensitivity aren’t specs that meet agreeably. The Vega squeezes each mAMP’s hand too firmly; reasonable home-listening SPLs got going early on in the 20-40 zone. The least significant bit throwaway of such heavy downward attenuation resulted in a shrunken soundstage, treble grain and tack-flat dynamics. Pixelation too. Oh no. Stop.
The AURALiC unit needs to be partnered with a more insensitive power box for it to operate in the top third of its volume range i.e. one with a larger input sensitivity value.
AURALiC’s co-founder Xuanqian Wang had this to say: “The volume setting of VEGA is from 0 to 100 with 0.5dB each step. Based on my personal experience, if you are working with volume above 60, it is almost as perfect as 100. Settings between 40 and 60 are also OK without significant effect on sound quality. However if you are running mostly below 30 for serious listening, I would recommend a high quality pre-amplifier.”
“Based on my personal experience”. Remember that phrase – we’ll be coming back to it.
With two false starts under my belt I’d begun to worry that Class D bigotry might have basis in truth. The Mytek Stereo192-DSD (US$1595, review here) soon extinguished those fears.
Mytek’s entry-level consumer DAC is ultra-flexible. The output level can be adjusted by ‘trim’ menu settings and/or ‘Gain Pad’ internal jumpers. An analogue volume circuit and analogue input allows the Mytek to keep one foot in more traditional pre-amplifier waters. Concerns about bit-destruction don’t get a look in.
Balanced-connected, Sarmento’s monos allowed me to mine deep, deep, DEEPER the Mytek’s core character: smooth, refined, sumptuous…but perhaps a little reticent. The Mytek is even better over FireWire than USB – super-easy going for all-dayers and all-nighters. A DAC that’s real long-game player and possibly one of the most complete packages for less than $2k right now, hence its DAR-KO award. And if you’re wondering why I’m talking so much about the DAC here, it’s because of the mAMPs’ far-out reveal.
Satisfying some personal curiosity, the Mytek DAC + REDGUM RGi60 (AU$1800+, covered here and here) doubles up on those aforementioned attributes: super refined, super smooth, super-urbane. It’s a duo for those who like to party large but retain civility. No spilt drinks, no making out on the stairs, no 3am Police visit. What struck me here is how close the twin Wyred4Sound-ers get to the REDGUM’s (similarly dual-mono) E X P A N S I V E N E S S. Super-power not only brings control and tires that grip in the wet but spaciousness.
W4S mono-d transients cut cleanly but with more urgency than the REDGUM RGi60. As well working from a lower centre of gravity, the Australian integrated lands a more definite path through the music; the Americans are more fleet of foot, more diaphonous. The two are pretty evenly matched when it comes to bad-ass bass propulsion.
The big takeaway here is Wyred4Sound’s Class D mono blocks more than match the liquidity and tonal colour of the dual-mono, Class A/B design from REDGUM.
Bone or flesh? You need BOTH. You need structural-skeletal communication without having to cut away connective tissue. If an increase in megapixels brings with it thin and wiry acoustic mass you probably won’t get no satisfaction. Maximising resolution at the expense of meatiness and body isn’t a path to long-term nourishment. One must strike the right balance. The Wyred4Sound mAMPs keep both ends of that see-saw off the ground.
The REDGUM shows hints of being fattened up for the Christmas plate – connective tissue is more obvious. However, don’t think the mAMPs are boney or skeletal – they aren’t – separation here is in a class above the Aussie integrated, perhaps more the equal of their RGi120. Bone AND flesh get S P A C E D O U T.
Then came the ultimate DAC-a-dance partner: Resonessence Labs’ INVICTA Mirus (CA$5000), a Canadian-built DAC specifically designed for this kind of direct-connect playtime. Despite a 4.6v balance output level, I had the Mirus operating between -30db and -20db for comfortable-to-loud listening levels. The spec-sheet speculation pointed in one direction – a mismatch – but based on my personal experience, listening sessions went the other – major gratification.
With exemplary bass tautness drama and scale get writ large; macro-dynamics – check. Sit for a couple of minutes in front of the electronic assault of The Flashbulb’s Hardscrabble and you’ll quickly learn that the Mirus + mAMP impact isn’t reserved for the lower frequencies. It’s not forward or aggressive, it’s just very present. VERY. Cairbou’s “Swim” is more immediate/arresting/palpable, clarity and micro-dynamics rendered with balletic grace and poise.
Did I mention that the mAMPs are deep-space silent? Put your ear to the speaker and you’ll hear nothing, zilch, nada. Building on a background as black as that, it’s little wonder that the swing-and-swagger of the Mirus is lively with a capital L.
The INVICTA Mirus contrasts the Mytek as smoother and introverted by being 1) less opaque and 2) MUCH bigger on micro-dynamic jump factor. The Mirus paints with deeper colour saturation and really delivers on spaciousness and ambient air. The chimes that puncture the surface of James Holden’s remix of Caribou’s “Bowls” ring with an arresting startle, the decay of which lingers for longer than listening via the Mytek. Everything with the Resonessence Labs DAC is bigger, bolder, and more bountiful. It’s a caffeinator, a lapel-grabber.
I don’t say this to kick the Mytek. Far from it. The Mirus is simply in a different class. It occupies a different price class too. Let us not forget that the Mytek stands apart from the competition with analogue input and a choice of analogue or digital volume attenuation. For these reasons alone the best return on your dollar sits with the New Yorker. The INVICTA Mirus is more idealism than pragmatism.
Seduction and intimacy are enjoyable traits. I know that from time spent with Earle Weston’s Topaz integrated. There’s none of that pleasurable euphonic personality with the mAmps. What you get is transparency poured into a voluminous three-dimensional soundstage. The mini monos’ polished window vibe allows truth, lucidity, and fluidity to flow freely…assuming your digital pre-amp is up to the task. If it isn’t, you’ll soon know. Think of Wyred4Sound’s mAMPs as the aural equivalent of an Apple Retina display; they’re a reviewer’s delight for picking differences between sources. I doubt you’d get closer to the music – or your DAC-pre – for less than $2k. Fans of electronic fare should run to these.
Part 2 of this review (with the matching mPRE pre-amplifier) can be found here.
Associated Equipment
- Resonessence Labs Concero HP
- AURALiC Vega
- Mytek Stereo192-DSD
- Resonessence Labs INVICTA Mirus
- Light Harmonic LightSpeed USB Cable
- REDGUM RGi60
- KEF LS50
Audition Music
- Caribou – Swim (2010)
- Caribou – Swim Remixes (2010)
- The Flashbulb – Hardscrabble (2013)
- Bob Dylan – Another Self Portrait (2013)
- The Blow Monkeys – Limping For A Generation (2012 remaster)
Further Information