Mytek HiFi Brooklyn AMP+ power amplifier

Big changes are afoot at Mytek. First up: The Mytek Brooklyn AMP+, the newest version of the compact, class-D Brooklyn AMP. The AMP+ is already in production.

In my 2018 review of the original Brooklyn AMP, I wrote that the class-D amplifier exuded "a consistent sense of truthfulness, striking resolution that was never analytical, spacious soundstages, superb dynamics, and some of the 'blackest' backgrounds I've ever heard...with the right recordings." I continued, "The AMP let me revel in its reproduction of the low end, with zero overhang or bloat, and profoundly impressive retrieval of micro- and macrodetail—but in doing all this, its touch was always light and never surgical."

Since then, Mytek president, founder, and chief designer Michal Jurewicz has been busy. Late last year, the company split from its longtime collaborator HEM, which operates the factory in Poland that has been making most Mytek products on contract for years. Because of the split, every Mytek product was discontinued. With the start of the pandemic, Jurewicz temporarily vacated the company's Greenpoint, Brooklyn, headquarters for sparsely populated upstate New York where, freed from everyday busy-ness, he designed new products and planned out the company's rerouted future. Plans were made to introduce whole new product lines and to update the company's existing products. First up, the Brooklyn AMP+ ($2495).

Why class-D?
I asked Jurewicz. "Class-D amplifier topology is based on one very sound principle," he responded via email. "If class-D topology is realized perfectly, the amplifier transfer function would be a straight line, meaning the amplifier will be perfectly linear with zero distortion. The challenge is to get the output squarewave as close to an ideal square as possible. When this is accomplished, the unit not only sounds better; it is also more efficient." Add to that efficiency light weight, far less heat dissipation, and plenty of power in a compact space, and it's easy to see why many audio manufacturers have entered the class-D amplifier market.

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My first Stereophile review, in 2016, was of the Spec RPA-W7EX Real-Sound power amplifier, a class-D amp that measured badly but impressed Art Dudley and me. "This modest-looking amplifier was positively surgical in its retrieval of low-level information," I wrote, "yet it achieved the not-so-easy feat of doing so without sounding sterile or clinical."

In the five years since, many class-D amplifiers have been released, evidence that class-D sound has found favor as an alternative to heavy, conventional solid-state amps and often hot-running tube amps. The quality of class-D amplifiers has improved and grown more consistent.

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On its exterior, Mytek's AMP+ looks no different from its predecessor, except for the plus sign in the logo. Its dimensions are the same—a "half-rack"–sized 8.5" wide × 1.74" high × 9.5" deep—as is the machine's faáade, its textured finish resembling polished alligator skin, in black or silver. Pushing a small, front-mounted button powers the amplifier; the "M" logo, backlit in your choice of colors, fades when it's powered down. Back-panel inputs and outputs are unchanged: one pair of balanced (XLR) and one pair of unbalanced (RCA) inputs, an IEC AC jack, and two pairs of binding posts for speaker cables. Nine tiny DIP switches enable conversion of the AMP+ from stereo to bridged mono; you can accomplish the same thing by downloading and installing Mytek's Control Panel app (which also lets you set the color of the front-panel backlight).

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The AMP+ employs class-D modules from Danish firm Pascal A/S, modified by Mytek. The power specifications are impressive, especially considering the small package size: 250Wpc into 8 ohms, 300Wpc into 4 ohms, 400Wpc into 2 ohms. It's bridgeable to produce a mono amp that can put out 500W into 8 ohms and 600W into 4 ohms.

The original AMP included stick-on nubs for feet. The AMP+ has proper screw-on rubber feet.

Inside is where the main changes are. "We changed the MOSFET transistors of the AMP to be at least five times faster," Jurewicz told me. "The AMP+ has more detail, which results in a larger, deeper, more 3D soundstage. There's a faster clock, from 450kHz to now 653kHz. This allows us to move the output filter [higher], which translates as more air, a lighter top end. It's less analytical and makes the sound finer with a wider array of speakers. Class-D amplifiers will typically always have this filter, which is essentially a coil and a capacitor, on the output; that's supposed to turn the squarewave into regular sound, typically around 30kHz. When you move the filter up, it improves the sound because it affects the audio less." The output filter frequency in the AMP+ has been increased to close to 50kHz.

"Sometimes, when people listen to the AMP+ version," Jurewicz continued, "they say that the older Brooklyn AMP had this nice midrange, which is essentially a grunge produced by distortions, but it seems to be acceptable in the older model. The new model is cleaner, with a bigger soundstage and more detail. The AMP+ is more precise. I would look to achieve that midrange sweetness of the earlier AMP through other means, using other components that are in that direction. "The price of the Brooklyn AMP+ is the same as the original: $2495. Your Brooklyn AMP can be upgraded to AMP+ status for $500 at the company's Brooklyn headquarters. An upgraded AMP and a newly manufactured AMP+ are electronically and functionally identical, Jurewicz says (footnote 1).

Listening
I assessed the AMP+ against the AMP using Schiit Sol and Kuzma Stabi R turntables (the latter with the Kuzma 4Point arm and Koetsu Rosewood cartridge). I also used a Mytek Brooklyn DAC+/preamp, and Klipsch Forte III and RP-600M loudspeakers. A 6' pair of Shindo XLR-to-RCA interconnects connected the DAC/preamp (used as a phono preamp and for volume control) to the Mytek amps. Auditorium 23 speaker cables connected the AMP+ to either the Klipsch RP-600Ms or the Fortes.


Footnote 1: Indeed, the sample under review is a former Brooklyn AMP, upgraded in Brooklyn to AMP+ status.
COMPANY INFO
Mytek Audio
148 India Street, 1st floor
Brooklyn, NY 11222
(347) 384-2687
ARTICLE CONTENTS

COMMENTS
tonykaz's picture

"best sounding" in the next few years ?

Thats a Strong extrapolation but coming from you I'd tend to embrace it. ( probably because I want it to be true )

I'm anxious to see the Class D Schiit and/or the Audio Research offerings.

Fingers crossed,

Tony in Venice Florida

ps. that lit front panel might be enough to push this device into a Buy-it-Now! event ( along with: Made in Poland, of course )

georgehifi's picture

"best sounding in the next few years ?"
"Thats a Strong extrapolation but coming from you I'd tend to embrace it. ( probably because I want it to be true )"

Follow what amps are using the new GaN fet as outputs, and it's believable.

Cheers George

a.wayne's picture

Class D amplifiers can’t pass Squarewaves so how do they have a perfect TF ..?

Regards

That Other Guy's picture

a bit edgy.

JRT's picture

All audio amplifiers are bandwidth limited devices. The woofers and tweeters that they power are bandpass devices, and likewise the microphones. The better question to answer is how much bandwidth is needed to be fully sufficient for the recorded audio signal.

a.wayne's picture

https://www.stereophile.com/images/421Mytekfig02.jpg

Like its predecessor, Mytek's Brooklyn AMP+ is indeed a tiny powerhouse. It matched the measured performance of the original Brooklyn AMP in most ways but with a wider small-signal bandwidth and a lower level of ultrasonic noise. Even with its hair-trigger protection circuit, it will offer sufficient power into low-impedance loudspeakers with music signals.—John Atkinson

Ohhh please John , its an 8ohm amplifier and barely will sink sufficient current to deal with 4 ohm loads forget 2 .

Regards

Ortofan's picture

... the $2K NAD C 298 class D power amp, which uses the Purifi amp modules?
Tests have shown that it is capable of a continuous output of 260W @ 8Ω and 516W @ 4Ω.
https://nad.de/wp-content/uploads/2020/11/NAD_C298_Test_Stereo.pdf

John Atkinson's picture
Ortofan wrote:
Will there soon be forthcoming a review of the $2K NAD C 298 class D power amp, which uses the Purifi amp modules?

Kal Rubinson reviews the C298 in the June issue.

John Atkinson
Technical Editor, Stereophile

JRT's picture

I am looking forward to reading Kal's review, and your measurements and associated comments.

JRT's picture

From the NAD press release at the link below, "The Eigentakt modules are manufactured by NAD under license from Purifi, allowing NAD to optimise these specifically in combination with the custom designed power supply and input stages of the C 298."

https://nadelectronics.com/nad-intros-c-298-power-amplifier-with-purifi-eigentakt-amplification/

So there are no Purifi Eigentakt amplifier modules utilized within the NAD C 298, rather are modified designs manufactured under a technology license. It will be interesting to see if the design modifications and optimizations were more toward improving cost or performance, or perhaps both.

If somebody does not need to bridge the modules, they might do well to consider the Audiophonics LPA-S400ET which uses two off the shelf Purifi Eigentakt 1ET400A amplifier modules, one Hypex switch mode power supply module SMPS1200A400, and Audiophonic's in-house design interface board. Price is €1,124.17 plus S/H (taxes/duties?) from France. I have no affiliation. There are similar competing products from others, but Audiophonic's looks to be nicely assembled and includes cooling slots that some others seem to not include. The interface board includes balanced differential input and single ended input, includes a couple of choices in gain, and includes facility to bypass the input stage to drive the modules directly with outboard gear (if that upstream device can swing 10_Vrms differential output across a 2_kOhm load).

tonykaz's picture

Today Mr.Stoddard said: looks like the Sol will not continue in production.

I'm not giving a accurate quote here, just paraphrasing .

Schiit are doing a broadcast from the Texas Location, a tour of the Building with workers working and a rather long Q&A for Jason from the Audience.

Seems like the Sol is too much of a commitment ( my summary ).

I agree, my Retail outlet, Esoteric Audio, was a Turntable, Arm & MC Cartridge Specialist . It was great fun that involved Tons of critically technical workings accompanied by ample room for disruptions in quality. We maintained a complete diagnostic service.

1985 CDs killing vinyl was an emotional relief. ( for my family )

Today, I feel for the Vinyl people as Chad's beautiful and pricy offerings require all the best & priciest vinyl paraphernalia and a significant monthly purchase budget.

Tony in Venice Florida

Jim Austin's picture

First, it's not certain yet, although it's very likely that the Sol will be discontinued.

Pure speculation here, on my part, but I suspect we'll see it again, or a version of it, once supply chains stabilize and they've had a bit more time to refine the design--not so much from a functional standpoint but from a sustainability standpoint: They need a 'table they can consistently and successfully build. Profitably, too.

Jim Austin, Editor
Stereophile

ken mac's picture

I'm really sorry and puzzled to hear that news. I thought the Sol was unbeatable for the $$$$. I really enjoyed my time with it.

Michael Fremer's picture

If they really are discontinuing the SOL they should license or give it away to someone else to manufacture. When correctly set up it sounded great for so little money. Yes it was “fiddly” but so was Heifetz!

tonykaz's picture

Thank you for writing back.

Mr.Stoddard explains that they are now selling 10X more than they forecasted and are experiencing acute Supply issues in every area.

They are also doubling in Factory Size with the two locations being 1,000 miles apart. ( I would NEVAH sign-off on an arrangement like that, these guys are designers not manufactureres )

I also suspect that these guys aren't Transducer specialists either. This player should've Sale-priced at $2,500 ( in my estimation ).

Overall, Schiit is HigherEnd Audio's Tesla type Company except they are growing much faster than their supply chain ( which seems one to two years behind )

For all us Schiit owners, Schiit gear sells for 80% of New Prices on eBay, residual values are outstanding.

Schiit is a Smash Success.

I was surprised that Stereophile reviewed the Sol but not surprised that Schiit can't quite make the darn things.

I wonder what a Cost Analysis would reveal.

Tony in Venice Florida

ps. Mr. Stoddard appears to have resigned himself to managing a Run-a-way demand situation accompanied with a backordering dilemma .

ken mac's picture

Well stated!

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