Master Sound 845 mono amplifiers

Master Sound 845 mono amplifiers
Hidden Jewels


 March 2010



Over the years I have traveled to many high-end shows and listened to many systems and I’ve always had a soft spot for the sound of tubes. Call me a romanticist. There is something about tubes which is musically captivating and intoxicating – especially when listening to classical, un-amplified music. It’s ironic that, as much as I love the tubes, I use solid-state for my reference system. Karan Acoustics in fact, over tube as I wanted electronics which delivers more power (with less heat), dynamics and control, with a midrange magic that rivals vacuum tubes without the maintenance and headaches. Yes, Karan’s midrange is excellent as far as solid state goes. Very close to best of tubes, but still to my ears – as I’ve discovered in my quest – it’s not quite 100% “tube magic”. I wanted an amplifier that was trouble free and no-maintenance. This has kept me away from tube amps all these years.

My first experience with an all-tube system proved mind-bending. It was a system that featured the exotic looking Jadis series of electronics of France driving a huge pair of Eggleston Savoy loudspeakers. This was back in the hey-day of high-end audio (somewhere around 1989). Mr. Woo who lives in Korea, is a true audiophile in every sense of the word. AND, he just so happens to be my father-in-law. He owns an impressive vinyl collection of more than 3000 LPs (mostly classical). I will never forget the experience. This all-tube rig rendered classical music superbly and was breathtaking with vocals, chamber music or orchestral music. It was as if I were listening to a live ensemble in his room. I realized “tube magic” is real; not imagined. There’s was a thee-dimensional stage and most importantly, timbre and tonality accuracy that was remarkably natural. Fast forward to 2005: I had an opportunity to go back to Korea, visit my relatives and Mr. Woo once again. His system performed spectacularly as I remembered. It wasn’t like I was sitting on my hands either. I had amassed an impressive sounding system, albeit solid-state that I am very happy with. But surprisingly my reference system is not able to reproduce classical music in the way Mr. Woo’s system does. In one word it felt “alive”.

At CES 2009, I met designer of Master Sound electronics, Lorenzo Sanavi in the May Audio room (photo). I enjoyed listening and talking to the Sanavi immensely. His Master Sound Evolution 845 Integrated sounded wonderfully warm, natural and rendered classical music beautifully. I confess I have always had an itch to write a tube amplifier review. I got in touch with May Audio’s Nizar Akhrass and asked if I could write possibly on my experience with the Master Sound amplifier. He obliged to send me the Final 845 series mono amps. 

Master Sound of Vicenza, Italy, is famous for their in-house designed transformers. The company was founded by Lorenzo Sanavio’s father Cesare Sanavio, in 1994. Newer amps in current production were designed by Lorenzo’s brother Luciano Sanavio, an electrical engineer and a music lover. Thus, there are two distinct lines of Master Sound electronics: The original and the Luciano-designed series. Luciano Sanavio designed the Final 845 mono amps with a goal to arouse emotions and connect the listener with the composer and the performer in a natural life-like way. All Master Sound amplifiers are Zero Feedback, Class-A based designs. Each product is hand-built in stages and according to Master Sound, one amplifier can take up to a full week to manufacturer. Master Sound recommends a minimum of 200 hours burn-in to reach peak performance.

The arrival of the Final 845 mono amps arrived via UPS in two heavy corrugated boxes. Weight is about 75 lbs each but seem much heavier than that or I’m just getting older. Difficult to lift, they are tricky because they’re weight is mostly in the two huge transformers that make up most their heft Believe me, maneuvering these guys around wasn’t easy. It’s a job for two! The Final 845s are very visually stunning. They reminded of some kind of nuclear sub. Two 6SN7GTs input tubes and two 845 tubes housed in a tube-protected metal black cage compliment the top chassis (if you got kids and pets this is a good thing). Two very large transformers resembling nuclear reactors occupy rear real estate.

Oversized, hand-wound transformers are typical on SET amps, but Master Sound goes further; they are gigantic. Lorenzo Sanavio, in fact, is very proud of these transformers. He says they’re made of a special type of Lits wire, which means there is no soldering whatsoever. Sanavio also states “the number of windings per wire is a carefully guarded secret and there are numerous combinations of windings.” He also mentioned “Master Sound takes the building of their transformers very seriously indeed, so the windings are encased in a gravel and resin mix that makes it impossible for copycats to imitate. If anyone attempts to open or cut into a transformer to uncover its secrets, the gravel would destroy the transformer.”

The Final 845s operates in parallel, Single-Ended in Class A mode with Zero Negative Feedback. Two 845 tubes produce powerful, (for a SET amp) 50-watts per channel. The rear panel provides three heavy-duty binding posts, one neutral and one each for either a 8 or 4-Ohm tap (I preferred the 8-Ohm tap with my loudspeakers as it was slightly fuller and more natural). The Final 845’s bias is manual and was easily achieved using a multi-meter and small plastic screw driver. The Final 845 has but a single, unbalanced RCA input. Lastly, four built-in black anodized aluminum spikes were screwed on the each Final 845 to complete an otherwise easy assembly. After familiarizing myself to the sound of this amplifier, I replaced the spikes with Acoustic System International’s Top Line series of spikes/feet which, to my ears, improved the sound. All cabling was none other than the ASI Liveline series. 

Hidden Jewel!
My review pair was fully burned in as it has been on the reviewer circuit for many months. I was so excited. At last I finally had a tube amp in my system. When I first powered up the amplifiers, I was very pleased to notice that they were very quiet notwithstanding a very slight buzz heard when you place your ears at the speakers. I could detect no noise at my listening seat. A half-hour of warm up was the norm before serious listening sessions began.

Right from the git-go I was impressed. In fact, I found myself staying up well into the wee hours playing an awful lot of music. The Final 845 mono amps are quite musical and very different in their approach. For their modest 50-watt rated output, they delivered the music with weight and substance. Moreover, they are balanced and possess authority and scale. Surprised? Damn Skippy. The difference in their power is it has a “charm” to it. I’ve had powerful components before but none were both powerful and delicate. The Final 845s drove my Conspiracy loudspeakers with no problems. It’s all there: the gorgeous midrange that one expects (especially from an SET), very neutral, neither euphonic or syrupy. The Final 845s had extremely natural treble extension, very extended and sweet. They presented a beautiful soundstage, big, wide, deep, and very three dimensional. Damit, I can’t put my finger on it exactly – but the reproduction of music, especially un-amped classical music – simply sounds more natural.

I sat down for a long listening session late one evening, beginning with a taste of chamber music. It was one of my favorites, Haydn’s String Quartet in D, Op.64 N0.5 (“Lark”) performed by the Lindsay CD (DCA 1084), then Rossini’s Sonate a Quattro performed by Ensemble Explorations (HMC 901776), 
I’m reminded again of that remarkable naturalness. Each instrument displayed a richer, more fuller harmonic structure. There is a quality to the strings that is almost palpable. It’s like you can reach out and touch the vibrations with your fingertips. Transients have just the right combination of sharpness and air. String tones were organic and the various stringed instruments were differentiated by size and character not merely by the range of pitches they produced. The strings sounded with a beautiful lushness, and richness. Somehow they sounded more truthful. As great as my Karan amplifier is with strings, there’s no denying the tubes have a certain magic for me which is impossible to duplicate using anything else. So, in this regard, score one point to the Final 845s. 

The Final 845 amps were reminiscent of my experience in Mr. Woo’s space. Now that I have Final 845s in my system I can understand why people are easily seduced by the sound of Single-Ended-Triode amplifiers. When playing un-amplified classical music, they have the ability to connect this listener much closer to the event. The Final 845s lets you hear deep into the emotion of the music.

I got the impressions that the Final 845 amps were far more powerful than its specified 50-watts per side. They sounded big and impressive, but sweet and musically powerful. As far as power was concerned, I could freely push the big Final 845s as it plays much louder than I imagined. The bass is full and powerful even though it couldn’t match the thunderous bass and control of the Karan KSA 450. Comparatively, the Final 845s were a little soft around the edges. However, as good as the Karan KSA 450’s soundstage I did prefer the Final 845s ultimately. Of course, I‘m being critical. The soundstage was stunningly natural and so expansive that it at times it seemed to extend beyond the walls of my listening room in a more organic way than the KSA 450. Listening to the great Jaqueine du Pre XRCD of Elgar’s Cello concerto, or Sir John Barbirolli conduction the London Symphony Orchestra (EMI 7243 8 2677202 4) was moving and very emotional. Jaqueline’s performance was breathtaking and the Final 845s are easily able to scale the dramatic and powerful heights of the full orchestral crescendos. At the same time they preserved the playing of the soloist the sound is highly dramatic and powerful with sudden dynamic shifts that requires an amp with great authority. A lesser amplifier might sound strained and compressed, but it was no sweat for the Final 845s. 

The Master Sound Final 845s amps have opened my eyes and ears to the beauty of SETs. They have shown me what tube magic is when done correctly. I’ll be sad when trucker picks up the amps next week and I’ll be searching for more tubes amps to review in the future. Until then stay tuned! The Master Sound 845 mono amplifiers are my Stereo Times “Most Wanted Components” award winner. Highly recommended!!

Specifications: Mastersound – Final 845 Monoblock

Design: Parallel Single Ended in classe “A” 
Power: 2 X 50 Watts
Finals tubes: 2 X 845 
Drivers tubes: 6SN7 GT
Input: 1 X RCA
Input impedence: 100K Ohm
Output Transformer: MASTERSOUND
Load impedence: 4 – 8 Ohms
Negative feedback: 0 dB
Bandwidth: 8 Hz / 30 kHz – 0 dB
Dimensions: 63 X 27 X 30 cm. 
Weight: 34 Kg/75 lbs. Per unit

Price: $14,995.00 US dollars

Importer:  May Audio Marketing, Inc.

2150 Liberty Drive, Unit 7,
14304-4517, USA
Phone: (800)554-4517 / (716)283-4434
Fax: (716)283-6264
Sales Inquiries: 


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