Ayre Acoustics EX-8 2.0 Integrated Hub D/A integrated amplifier

In New York City, everything comes at a premium: Housing, groceries, transportation, walking space, living space, sanity space—consider our cubbyhole apartments and tenement buildings. Even "air rights" are for sale in NYC, including rights to the air over my beloved Katz's Delicatessen in the Lower East Side (footnote 1). The square footage of my downtown apartment is less than a quarter of the space of my North Carolina home. (Brownstones? Only above 72nd Street, footnote 2.) But, as the song says, "If you can make it here, you can make it anywhere." What did Frank Sinatra know, anyway? He was from Hoboken!

In places like this—indeed anywhere there's a reason to keep things compact—there's an argument to be made for an all-in-one music source. Today's integrateds often include independent preamp and power amp sections, a phono stage, a D/A converter, streaming capability, a headphone output, and apparently the ability to simultaneously fry an egg and book a flight to High End Munich 2021, if only it weren't cancelled.

I'm lucky to have three integrated amplifiers in-house: the Heed Audio Elixir, the Parasound Hint 6 Halo, the Schiit Audio Ragnarok 2, and the component under review, the Ayre Acoustics EX-8 2.0 Integrated Hub ($8350).

In his January 2019 review of the original Ayre EX-8, Stereophile Technical Editor John Atkinson wrote, "I used Ayre's EX-8 for almost all my serious listening from the summer through the early winter of 2018, and in all that time I only rarely felt I was missing something sound-quality-wise. ... The EX-8 Integrated Hub is a high-end contender at a competitive price." With its substantially updated design, the EX-8 2.0 should be even better. So, is it?

Design
Since JA1's review, Ayre Acoustics' Ariel Brown, who succeeded company founder Charles Hansen as chief technology officer when Hansen passed in 2017), oversaw a series of changes to the class-AB EX-8. Brent Hefley, Ayre's director of sales and marketing, outlined the changes in a series of emails.

"Customers wanted a bit more power. So, we've doubled output devices to four per phase, eight per channel. This will allow the EX-8 2.0 to drive more difficult loads and increase its power output into 2 and 4 ohm loads," Brown explained. "The board in the EX-8 was designed as kind of a universal platform for several possible products, including the upcoming VX-8 stereo amplifier. It already had allowances for the extra output devices and bulk capacitors. Beyond that, the changes are primarily to resistor values."

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"Capacitance: We've doubled this as well," Hefley continued. "The increased output capacitance helps deliver more power to difficult loads as well as improve the bass response and dynamics." Brown also optimized the bias and output impedance of the amp's "double diamond" output stages, "creating better detail, musicality, and spaciousness," Hefley told me.

I won't pretend to be equipped to explain the diamond circuit, so let me quote Art Dudley, who could expound on technical matters in readable fashion better than anyone.

"That all-but-forgotten" diamond circuit, Art wrote in his August 2013 review of Ayre's AX-5 integrated, consists of a "gateable bridge network of four bipolar transistors first described in 1964. Imagine, on the left-hand side—the signal-input side—a PNP transistor, and, below it, an NPN transistor, tied together at their bases; and, on the righthand or signal-output side, an NPN transistor and, below that, a PNP transistor, this pair having their emitters tied together. The emitters of the left-hand transistors are tied to the bases of the adjacent right-hand transistors, and the collectors are biased all around: negatively in the case of the PNPs, positively for the NPNs. When drawn in the manner I described, with connecting nodes at north, south, east, and west, the schematic assumes a diamond shape, hence the name."

Channeling MIT's Richard Baker, who was awarded the patent for the diamond circuit in 1967, Art continued: "It can operate effectively in a floating or above-ground condition; it can produce considerable power gain; it's reliable; it's fast; and, perhaps best of all, the diamond circuit is simple."

Here's Charley Hansen's take, as expressed, once again, by Art: "The diamond circuit, used as an output section, simply sounds better. ... Hansen suggests that when compared with other solid-state push-pull topologies—in which two phases of a signal are recombined to form a full wave—the diamond is the only one in which the two half-signals are joined at a single point in the circuit, with no intervening circuitry. Thus, the diamond circuit creates an output that's more faithful to the shape of the input." (footnote 3)

The EX-8 2.0 was introduced in March 2021 at $8350 for the fully loaded version, which is the version I have in for review. "With the Ethernet module installed," Ayre's website states, the EX-8 2.0 is "Roon-ready and pre-configured to stream Spotify, Qobuz, and Tidal."

The amp includes three analog inputs (two RCA, one XLR) and a "Digital Base" of six inputs including S/PDIF, AES3, USB, and Ethernet. There's also a sub/preamp out (RCA and XLR), which I've used for previous reviews. There is no phono stage. The EX-8 2.0, like the previous EX-8—and like all Ayre amps I'm aware of—uses fully balanced, zero-feedback circuitry. The EX-8 is specified to output 100Wpc into 8 ohms and 170Wpc into 4 ohms; the latter is about 45 watts higher than the original. It runs slightly hot to the touch when making music, slightly warm in standby mode. Because of its modular design, the EX-8 2.0 can be updated as your mood and wallet allow. Existing EX-8s can be upgraded to fully loaded 2.0 status for $750.

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Standing 17.25" wide, 4.5" high, and 13" deep, and weighing 24lb, the Ayre EX-8 2.0 is handsome, even svelte. Soothing the eye with its gently rounded corners and brushed silver or black aluminum casework, the EX-8 2.0's recessed, split-level front panel offers two fingertip-sized buttons enabling choice of inputs (B1, S1, S2, USB, Optical 1, Optical 2, S/PDIF, AES3, Network, "Ayre-link"), followed by a digital readout screen and then a large volume knob. Two 3.5mm jacks for balanced headphones and one single-ended 6.3mm headphone jack cover most standard headphone configurations.

The amp's large, diagonally placed Cardas binding posts work best with spades. The banana plugs of my speaker cables did the job, but I had to push them in hard to make them fit securely. Ayre Acoustics CEO Ryan Berry sent a pair of adapters that worked perfectly and didn't stress my cables' banana plugs.

The EX-8 2.0's design is straightforward, right down to its utilitarian plastic remote, which handles input and volume. For an extra $100, Ayre will supply a dedicated, slim'n'silky metal remote that better complements the EX-8 2.0's design.


Footnote 1: For those unfamiliar with the concept: Buildings below the maximum height allowed by neighborhood zoning restrictions can sell the rights to their unused vertical space for use in a neighboring building. Several years ago, Katz's Deli made a deal to sell the five stories of air rights it owned and some neighboring real estate to a developer, allowing the construction of a tall building next door. Reportedly, the deal ensured the long-term survival of that iconic New York City restaurant.

Footnote 2: Wherever you find them in Manhattan, brownstones are beyond the means of the vast majority of New Yorkers.—Jim Austin

Footnote 3: Here, Art added a footnote: "This, if you don't mind my saying, teeters on the verge of saying that the diamond output is closer than other push-pull circuits to the single-ended ideal. You are free to imagine a smiley emoticon at the end of that sentence."

COMPANY INFO
Ayre Acoustics
268 Monarch Park Pl. Suite B
Niwot, CO 80503
(303) 442-7300
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COMMENTS
Allen Fant's picture

An excellent review. If this model is half as good as the AX-5 Integrated, it is a keeper.

CG's picture

I guess this proves, once again, that all manufacturers send special high performance non-standard products to reviewers for review in front of the world.

(Insert rolling eyes emoji here.)

michelesurdi's picture

what this proves,once more,is that inadequate packing equates to manufacturer profit and customer loss.

CG's picture

Umm...

"It appeared that the review sample had suffered some kind of shock in transit from Ken Micallef's place to mine—the top panel was dented—"

That's on the manufacturer? They didn't do the packaging for that part of the journey. You still could be right, but...

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