August 2014

Synthesis Art In Music A50T Integrated Tube Amplifier With DAC
A wonderful ability to recreate a realistic stereo stage.
Review By Ron Nagle

  In the land of pasta and pizza you can find the Synthesis Art In Music that manufactures the Action A50T. This tube powered Integrated Amplifier embodies some old and new component technology flavored with a pinch of Italian industrial design. It is not just an integration of a preamplifier and power amplifier with the usual analog line level inputs. But additionally it contains a high quality digital capability via a 24-bit/192 KHz upsampling Wolfson DAC. Let me state that this is by far the most substantial $5295 'built like a tank' 50 Watt integrated amplifier that I have ever had the pleasure to audition.

Details
Nuts and bolts basics: First off there are two things I really like to see. The A50T is an ultra linear push-pull stereo amplifier. (This circuit was developed by Alan Blumlein and patented in 1937) My sample is equipped with four J/J KT88 power tubes made in the Slovak Republic. For one channel, the driver stage uses one 12BH7 tube while the input section employs a single 12AX7 dual triode. With the exception of the KT88 power tubes the tube filaments are quietly DC powered.

Specifically this amplifier is rated at 50 Watts per side into 6 Ohms using two KT88 tubes per channel. My preference in this Ultra-Linear amplifier design is the use of KT88 output tubes. There is a camp that loves the warm sound of classic EL34 tubes. And there is another following preferring 6550 Pentodes serving up a faster more detailed sound.  But to my mind the KT88 sound falls just in the middle of these tubes and it incorporates the best characteristics of each design. The KT88 tube provides a detailed sound but still retains some sense of real life with natural sounding warmth. Not incidentally the A50T has an auto bias circuit that allows you to substitute different types of output tubes such as the KT77 and 6550 Pentodes. The oversized custom made power and output transformers accounts for most of this amplifier's 77 pounds. As you would expect the amplifier is rectangular and measures 19" Deep with a 16" wide front panel and it is 9.25" inches high. The A50T is encased in a cold rolled steel chassis and tube cage; both are covered with a sand textured black paint.

On the 5/8inch thick black anodized aluminum center panel there is a very distinctive really large black volume control knob. Why so large? I don't have a clue, possibly a hint of Italian architecture? Moving right along, the oversized black knob and the power and source selection buttons are all mounted on a brush finished aluminum front panel (accent) strip. The left side of this panel has a round lighted power/stand by button. However the main power switch is actually on the rear chassis just below the power cord IEC socket. So a cautionary warning, AC power is always present internally. When activated the front panel power switch starts a diagnostic turn on sequence. Over at the right side of the amplifiers face there are six source select push buttons and above each button is a red LED. The power on sequence will begin to scan all six inputs.

When the tubes reach operating temperature, the scan completes and the last input that was in use is selected. At this time we see something that is contrary to most amplifiers, the illuminated power on button turns off. Two of these input select buttons are labeled with a unconventional designation. Arranged from left to right the inputs are: CDP, DVD, Radio, SAT, then the two Digital inputs are, USB and S/PDIF. No matter how the four analog inputs are labeled they will all accept conventional line input sources. The USB connection allows you to use the amplifier as a computer sound card that will support audio data up to 16-bit/48kHz stereo. The other digital input is the S/PDIF Digital audio input and below that is a fiber optic digital TosLink connection. Both will support PCM 32 to 192 kHz and 16 to 24 bit stereo. At the rear of the amplifier all of the input jacks are unbalanced RCA type connections with the exception of the one TosLink fiber optic connection; this is labeled as a USB input. At the rear of the amplifier there is an additional set of RCA jacks labeled, Preamp Out. This can be used for the addition of another power amplifier or subwoofer controlled by the main volume/gain control of the A50T. Also on opposite sides of the rear chassis are pairs of WBT left channel and right channel speaker cable binding posts. Most of the amplifier functions are mirrored by the milled aluminum hand held remote control. There are six buttons corresponding to the six source push buttons on the front of the amplifier. In addition there are two buttons that will increase or decrease volume and two more labeled Standby and Mute.

What Does It Sound Like?
By me, first impressions are very important. You have to take into account the ability of the human brain to adapt to sound and block unpleasant noise. Do you remember the last time you flew on an airplane? After a time the drone of the plane's engines became a background noise and you could talk or even take a nap. Citing a note from the A50T owner's manual it tells us that it will take 30 minutes before the amplifier is optimized for listening. Having done that, I found a sweet spot with a very pleasant view. I usually just let my Sangean Digital tuner pipe FM music in to warm up my system. But this time around even this mundane source managed to turn my head.

Dimensionality
Even listening to FM radio and Pop Rock tunes the A50T could delineate layers of depth extending from the speaker face to the wall behind my system. It was not simply an expansion of space, rather it contained distinct layers. At times I heard four lateral cross sections, front, middle, rear, and with certain recordings a more distant echo. Listening too, a demo of Fanfare For The Common Man, Eiji Oue conducting the Minnesota Orchestra. The A50T has an envelope of sound that paints the Kettle Drum reverberation and the Trumpet echoes to tell you the dimensions of the concert hall. The ambiance imparts a 'you are there' sense of inhabiting the vast space of the concert hall.

Intonation
My yard stick is and always has been the sound of a human voice, this is what I know best. It is really all about intonation and phrasing this is the primary elements defining a vocalist's signature style. I went scrounging and arbitrarily grabbed one of my SACD disks. This turned out to be a multi-layer demo sampler from Groove Note [GRV1023]. Some of the artists on this disk are new to me. And as it turned out this disk proved to be a great vocal selection, the entire SACD is crisp clean and highly detailed. Imaging is rock solid and revealing of ever deepening layers of studio multi tracking. Listening to cut three Tania Maria sings the title track from her album, Come With me. The best thing about the track is this vocalist, not only can she sing but she can phrase Scat and do it in close harmony with an electronic keyboard. The keyboard and her voice on this track follow so very close so that it is difficult to separate the singer from the instrument. Her scat progression follows the keyboard note by note and her phrasing is pitch perfect.

Transient Response And Dynamics
Both qualities are present on a wonderful concert disc. This is a recording from Avatar Studios in New York City, of the Afro Latin Jazz Orchestra Live at Lincoln Center. This concert was recorded March 13, 2004. This wonderful plangent performance is interspersed with audience applause echoing from the open space of the concert hall. All of the cuts on this CD are comprised of dense instrumental band arrangements. Listening to track 9, a Bolero, Como Fue is a Cuban ballad. It opens with a melodic refrain from a clarinet blending and then trailing into an accompaniment with a trumpet and saxophone. The score is comprised of intertwining brass instruments with piano. All of these propelled by a driving tempo driven by Conga  drum along with a drum set, sound accented by cymbal splashes. The important thing to convey is not just the wonderful instrumental scoring of this concert. But the wide open ambient sound and the delineation of instrumental elements, each separate element flows together to draw you into the performance.

Empirical Observation
The A50T runs hot, so I kept a small fan pointed at it. Starting from room temperature the amplifier always sounds better after it's been on for about a half hour. Also, placing two VPI magic bricks on the rear transformer cover made a slight, yet noticeable improvement in imaging resolution. Three types of outputs are available simultaneously from my Marantz 8400 Universal CD, DVD, SACD, and DVD-A player. These are left/right unbalanced RCA analog and two digital sources S/PDIF and Fiber Optic TosLink. I decided to compare the Marantz analog and digital sources by switching between the S/PDIF and Coaxial outputs while playing a Red Book 16-bit/44.1kHz. CD. I found at this juncture there was no appreciable difference in the sound quality. However if playing a SACD disk the RCA coaxial input is active but the S/PDIF digital input is inactive. This is to be expected since the dual mono 24-bit/192kHz Wolfson DAC's will not process the 2.8224 MHz one bit sampling rate of the Sony SACD format.

Summary
Every stereo component has the potential to bring us something of value. The A50T brings everything that has kept tube amplifiers alive and well. It has an organic and human quality hard to define. When compared to other Hi-End amplifiers it will serve as an example of just how far tube design has evolved. All of the analog sources and digital sources benefit from the dimensionally layered sound of the A50T. The Synthesis A50T has a wonderful ability to recreate a realistic stereo stage. It creates a clear stereo dimensionality without exaggeration and is equal to anything I have had the pleasure to audition. All the while at the deep center the image is just as wide as the space between the stereo speakers. The bass has a tube like tonal structure with overtones that lets us resolve details of the physical structure (in this case) of the kettle drum or the wooden body of a Bass Fiddle. This makes it possible to infer the size shape and material from which these instruments are made. From the very first the Action A50T amplifier found a home in my home and I much preferred to just sit and listen. Anything that transports me out of my chair and moves me into a concert hall or even into a music mastering studio, that's what a music system is all about.

From me, Semper Hi-Fi and remember to enjoy the music!

Review System Components
Source Components: Sangean Digital tuner, Marantz 8400 Universal CD/SACD/DVD/DVDA player.

Amplification: Synthesis Action A50T Integrated Tube Amplifier, Sanders ESL power Amplifier.

Speakers: Aurum Cantus Leisure 2 SE two way monitors on 24-inch stands, Mark & Daniel Omni Harmonizers, Add on Tweeters.

Speaker Cables: Kimber Kable 12tc 8ft.

Interconnect Cables:

AC Power: Wire World 10 gauge IEC line cord, Kaplan Kable 1.5 Meter 3 pairs power cord, IEC Islatrol Industrial 20 Amp AC line conditioner, Richard Gray 20 amp Sub Station, Alpha Core Balanced Transformer Power Supply, Audio Power PE-1 power enhancer, Triad 2-Ampere isolation transformer (line filter for digital sources).

Specifications
Type: Vacuum tube integrated amplifier with DAC
Tube Compliment: Two KT88, 12BH7 and ECC83/12AX7
Frequency Response: 20 Hz to 20 kHz
Input Impedance: 50 kOhms
Output Impedance: 6 Ohm
SNR: >90dB, A weighted
DAC: 24-bit/192kHz Wolfson chip
Inputs: RCA gold plated connectors, USB and S/PDIF coax RCA 
Output: Preamplification output via RCA jacks plus gold-plated loudspeaker binding posts.
Dimensions: 19" x 16" x 9.25" (DxWxH)
Weight: 77 lbs.
Price: $5295

Company Information
Synthesis Art In Music
Via Vanvitelli, 14/A 
62010 Morrovalle (MC)
Italy

Voice: +39 0733 567474
Fax: +39 0733 567154
E-mail: info@synthesis.co.it 
Website: www.Synthesis.co.it

United State Distributor

Voice: (847) 400-7564
E-mail: info@metropolitanmusicdistribution.com
Website: www.MetropolitanMusicDistribution.com