The Tact Audio 2150 Amplifier

Of all the audiophile components available today, I’ve never seen a product that’s so loathed and beloved as Tact Audio’s digital products. Digital was supposed to be the perfect sound when it was introduced a couple of decades ago. With all the advancements duly noted, audiophiles contend that vinyl still rules. They argue that vinyl is analogue, and that digital is a facsimile thereof. Digital today, thanks in part to yesterday’s pioneers like Forsell, Wadia, Accuphase, and Theta, helped dispel problems associated with early digital sound: hard, antiseptic, cold, and uninviting. Today’s new digital mavens, such as Ed Meitner of Meitner Labs, Zanden Audio’s Mr. Yamada, Electrocompaniet’s Per Abraham, and Radimir Bozovich of Tact Audio, the subject of this review, have elevated digital technologies still further. 

My first and quite vivid memory of Tact Audio began when they debuted the Tact Millennium, the world’s first digital amplifier, at the ’97 Stereophile Show. Shortly thereafter, Tact introduced the world’s first room-correction preamplifier with the Tact Model 2.2 (which I subsequently purchased). The Tact 2.2 served as my longstanding reference (if you’ve ever heard what this gizmo has done in my room, you’d know why). Until, that is, the long-awaited Tact 2.2X, a much more sophisticated version replete with digital ins and outs, replaced the original. 

Also new is their complete reworking of the Millennium amplifier in the less expensive Tact M2150. Costing $4,900 (less than half the price of the Millennium), the 2150 is also the first “true” digital-audio amplifier, since other digital or Class D and Class T amplifiers use analog inputs before converting them to a digital waveform, then back to analogue. The Tact 2150 employs pure digital Pulse Wave Modulation (PWM) amplification. PWM amplifies a digital signal and directly drives the loudspeaker upon conversion to analog. 

“Essentially,” says Tact, the hundreds of active and passive components usually required for amplification are simply not here.” This means, by conventional methods, the 2150 is not an amplifier at all. It is a D to A converter with enough power (current and voltage) to drive speakers directly. Unlike the many dozens of parts in conventional amplifiers, there is only a single coil and capacitor performing a 60 kHz, second-order low-pass filter after the D-to-A conversion in the Tact 2150, using Tact’s exclusive, proprietary PCM-to-PWM “EQUIBIT” technology. EQUIBIT, developed by Toccata Technology of Denmark, reduces the digital signal lengthwise to the speakers.

The Tact 2150 is as feature-laden as a Swiss Army knife. Multiple inputs (five digital and three analogue) qualify this digital dynamo as an integrated design in the most unconventional way. Built under the same roof as the still highly lauded but discontinued Tact Millennium, the Tact 2150 is a highly evolved version based on the same principles, 25 lbs lighter and $5k cheaper, while boasting greater resolution capabilities with the help of sophisticated 24-bit/192kHz digital-to-analogue converters. For more technical information, please visit Tact’s website at www.Tactaudio.com.

Turn Me On

One of the many superior benefits of the Tact M2150 digital amplifier over analogue ones is that it operates at close to 95% efficiency and thus does not run hot. The 2150’s lack of heat sinks helps keep this amplifier light and its appearance lithe. Don’t be fooled by the ripples along its sides; they were designed more for aesthetic appeal than for heat dissipation. The 2150 features a zero-feedback design and, at full volume (voltage), the power supply delivers a full 58 volts, equal to 150 Watts into 8 Ohms. To reduce the volume, the power supply’s output voltage is also reduced. This means the volume control has no active circuitry, which, by the way, has been proven to be an ideal method for excellent volume control, as Ed Meitner used it in his fabulous BiD years ago. Additionally, because the 2150 uses voltage modulation to control volume, it is purported to be impervious to clipping.

Physically, the 2150 looks like any Tact product, with its large, omnipotent master wheel that serves as both its volume control and the company’s greatest spokesman. The “M” in M2150 stands for Master version because it employs a separate volume control, while the $500 less expensive “S” or Slave version, designed to go in tandem with Tact’s preamps, does not. Mine arrived with the finely brushed black aluminum fascia (silver is optional). In terms of physical layout, the Tact 2150 looks pretty clean and simple, given its capabilities. Below the Tact Audio insignia, in the upper left corner, is the power button. Its Digital and Analogue selection toggle buttons are located on the left flank, while the master volume and mute buttons are on the right. A mere five buttons hide the Tact’s labyrinth of sub-menus located via its remote control.

Depressing the Tact 2150 power switch illuminates its front panel display that reads “Loading System…5…4…3…” counting backwards to zero before its main status screen appears. It is here, on the main screen, that you can begin to understand how sophisticated and unconventionally designed this amplifier actually is. Input selection (1 through 8) is also visible via the front panel. The selected input will be displayed on a corresponding status screen that indicates: input selection, Master level (in decibels), Input sampling frequency, and Master Level Volume, all in large, bold LCD numerals that are easily visible from my listening seat, 10 feet away. Sub-menu features such as Balance, In-Out, Polarity, Delay, Crossover, ADC (optional analogue-to-digital converter), Display, REM (remote), COMM (communication), and ADDR (address) are all accessible via the remote control’s toggle. When necessary, each of these sub-menus allows for even greater flexibility and control. For example, when I opted for a second 2150 to vertically bi-amp my Ascendo System M loudspeakers, all I had to do was grab the remote control, find the sub-menu’s COMM (communication) control, and program each 2150 to output left and right channels separately. This program, from the 2150s, performs like monoblocks with 300 watts per side. 

The Tact 2150’s rear-panel connector resembles a digital-to-analogue converter, but with speaker terminals. Three analogue inputs (two single-ended, one balanced) are sequentially allocated on its upper left, while five digital (three RCA S/PDIF’s, one AES/EBU, and one Toslink S/PDIF) are located beneath. All digital inputs support PCM audio data with sampling rates from 32kHz to 96kHz/16 to 24 bits. AES/EBU and RCA/coaxial inputs support a 192kHz sampling rate. One digital output serving as a pass-through comes as standard when using more than a single Tact 2150, as it becomes imperative. When analogue usage is selected, digital pass-through is disabled.

Intimidating? Yes. Hard to use? No!

Setup consisted of sitting each 2150 atop Kevin Tellecamp’s Silent Running Audio component racks, while all AC contaminants were being fed through Shunyata Research’s HYDRA AC distribution center via all their accompanying Anaconda AC cords. All cabling for this was done using the fabulous, expensive Analysis Plus Gold cables, strapped to the new and even more exciting Ascendo System M loudspeakers. AP’s gold is just that, and I admit I was more shocked by its performance than by its price. And at $5k per six-foot run, or $2k per meter, they’re neither cheap nor affordable. 

I must state for the record that the Bel Canto-designed Tripath Technology taught me, contributor Stu McCreary, and Dan “The Man” Dzuban a lot about what to expect from digital amplification. This amplifier still stands as a reference by which all others should be judged. It proudly stood as a reference point for me for more than two years, with many, much more expensive amplifiers finding their way back to their place of origin with a “sorry, I’ll pass” sticker attached instead of “how much.”

Tact-ical Assault on the Senses

What I heard during a full run of Analysis Plus via the digital link directly feeding the TACT 2150 was nevertheless staggering to my ears. This level of resolution was a bit unexpected. There exists a quality that is as immediate as it is astounding in the areas of silence, transparency, and naturalness. Never, in my experience, has my system sounded this quiet. I’m talking dead quiet with your ears on the tweeters. No hissing at all! More unnerving, however, was what became available via the TACT 2150’s digital signal from my couch ten feet away. Digital, I thought, wasn’t supposed to sound this natural and, well, analogue-like. Those were the exact words I murmured to myself the very moment I put on Dizzy Gillespie’s“Gillespiana CD” [Verve314519809-2]. I’m not certain if you’re familiar with Manteca but I’ve got to admit, I wasn’t as familiar as I thought after hearing through the TACT 2150. 

First, there is the unmistakable freedom from artifice. A peculiar clarity overtook the music, unlike anything I’ve encountered, digital or analogue, beforehand. Dizzy Gillespie’s Gillespiana is a 22-piece big band directed by Argentine Lalo Schifrin, which features jazz legends such as Clark Terry and Ray Barretto. Recorded in 1960, when panning too many instruments into one channel was probably considered an art form, needless to say, there is a lot to hear on this CD, literally. What I heard literally caught me off guard. Secondly, when you have dozens of instruments blaring the same chord and melody simultaneously, it’s very difficult, if not downright impossible, to differentiate between the French horn, tuba, saxophone, trumpet, and trombone. Yet, amazingly, somehow, the TACT 2150 recreated this brass section as individual instruments. More than ever before, I could make out each instrument at the very same time out of the corner of the soundstage.

Armed with greater validation than previously available, thanks in part to products like the Ascendo loudspeaker and Zanden, I just couldn’t believe how good the Tact 2150 actually performed. This digital dynamo revealed more nuances, hinted at more gradations, captured more of the music’s ebb and flow, and boasted more micro- and macro-dynamics while intimating more of what was on this CD than I would EVER have thought possible. Especially from a digital product! 

From the very top of the frequency extreme, say 17 kHz (measured), down to about 40 Hz, there exists a cohesiveness and synergy that allows me to hear the delicacy of a softly plucked harp and the thunderous effect of a mallet striking a tympanum simultaneously. On Reference Recording’s “Requiem” [RR-57] CD, track seven, entitled “Pie Jesu,” featuring the soprano Nancy Keith (a long-time favorite of mine), revealed underlying bass notes from the very powerful Lay Family Concert Organ, and this beautiful soprano in a delicate balance that never before sounded more authentic. Ditto bassist Charlie Hayden and guitarist Pat Metheny’s performance on ” The Moon is a Harsh Mistress from their Grammy-winning Beyond the Missouri Sky CD. I would also feel derelict in my duties if I didn’t include Muddy Waters’ classic CD, Folk Singer. This blues standard never sounded so good. Jacintha’s Here’s to Ben, proved to me why everyone should own this soulful CD. Lastly, one of my favorite releases is from the Chesky brothers, aptly entitled Entre Amigos. The wonderfully rich, tropical sound of Brazilian music is a happy addition to my much-needed Antonio Carlos Jobim collection, especially after my return from that enchanted country only a few days earlier. This latest release features songstress-guitarist Rosa Passos and legendary jazz bassist Ron Carter performing in a collaborative effort that is as tight and rhythmic as it is refreshing and soulful. CD after CD, genre after genre, whether Classical, Big Band, Jazz, R&B, or New Age, through the Tact 2150, it simply didn’t matter. The music that comes through via a digital coax cable is, literally, what is on the disc in all its glory-or in many cases, all of its warts.

You Want the Truth? You Can’t Handle the Truth!

As delightful as the Tact 2150 sounds, it doesn’t come without its quibbles. However minor they appear, they are valid points discovered only after many months of intense listening sessions. The first of my quibbles: because there’s so little filtering between the signal path and the loudspeaker, there’s little chance that bad or half-decent recordings will sound good. As a result, many CDs didn’t sound as good as I originally thought through the Bel Canto eVo2. On the contrary, I discovered that the eVo2 didn’t bring to the surface all the warts on each of my CDs, which was a good thing if you like your recordings to sound good. Worse, what do you do after you discover classical recordings don’t possess that warm, fuzzy feeling analogue amps provide, while jazz recordings sound better than ever? Talk about being in a catch-22. I’ve always wanted the truth and have felt intuitively that the 2150’s pros far outweigh its cons. Moreover, from a synergy perspective, attempting to frame the situation as a software issue rather than a hardware one wasn’t easy either. What’s a law-abiding audiophile to do?

Flip the Script… Add tubes!

It’s pretty much the gospel truth that tubes are superior in the areas of bloom, three-dimensionality, soundstage, and palpability. Feats that, however euphonically conferred, or even-order distorted, produce the most convincingly lifelike playback this reviewer’s ever heard. Just imagine the virtues of adding to those wonderful traits, the amazing transparency, relaxed presentation, tonal perspicacity, and the super-low noise floor that seems to be the very embodiment of the 2150. As you are very well aware, this hobby is built around synergistic combinations. Enter the Zanden Model 5000 digital-to-analog converter (review forthcoming). Here is a standard Red Book (16/44) DAC that offers no upsampling and lists for an astounding $10K. Yet this standard DAC’s ability to naturally render the music’s crux is better than anything I’ve heard thus far from an external processor, yes, reducing my mighty Electrocompaniet CD player to transport duties (and it is a damn good one at that). As good as the Tact 2150’s digital circuits are via the 2.2X preamp, or straight from the Electrocompaniet’s digital output, ultimately matching it with the Zanden, for this audiophile, proved to be a synergistic match that just couldn’t be denied. 

For the first time, the possibilities of what is best about tubes and digital became evident. No more slushy-sounding bass thanks to the Tact 2150’s speed and great damping abilities. No more hints of stridency in the high frequencies, thanks again to the legendary traits tubes are known to bring to string tone. I could go on and on, but I think YouTube lovers know what I’m saying. I am certainly a believer and am now using the Tact 2150 with the Zanden Model 5000 Mk III. Am I compromising the best digital has to offer by adding analogue back into the chain? I honestly don’t think so. But the most important question I believe should be asked is: Am I finally able to achieve the ultimate musicality I hoped for when I started this hobby? I would have to answer: Absolutely! 

The Tact 2150 proved to me what is possible in digital amplification today. Its transparency and natural sound surpassed any amplifier I’ve reviewed to date, besting the incredible Bel Canto eVo2, my former reference. For me, this marks an alternate route to audio nirvana. Any amplifier for less than $5k is a bargain these days. To have an amplifier that conjures up fond memories of what I’ve always loved and loathed about single-ended designs and solid-state devices, discarding all that’s bad while keeping the good under a single chassis, is not only a feat but, at this asking price, a downright steal. 

It would be, pardon the pun, tactless if I didn’t add three audiophile friends who, after hearing the Tact 2150 in my system, placed their amplifiers up for sale on AudioGon or eBay, and purchased Tact amplifiers.

clement perry

Specifications                                   

Power: (RMS) 2 x 150W / 8 ohm, 2 x 300W / 4 ohm
Output current: (peak, per channel) >50 A
Signal-to-noise ratio: ( A-weighted ) >110dB
Dynamic range: (20 Hz – 20 kHz) >130dB
THD+N: (all power levels 20Hz-20kHz) Digital resolution: 16-24 bit Linearity (-120dB) +- 0,2dB
Dimensions: (WxHxD) 450x98x420 mm
Weight: 18 kg / 37 lbs.
Price: M2150 $4,900.00; S2150 $4,400

Address: 
201 Gates Road, Unit G
Little Ferry, New Jersey 07643
Phone: 201/440-9300                                             
Website: www.tactaudio.com