Master Sound 845 Mono Amplifiers

There is a singular quality to the sound of a single-ended triode (SET) amplification device. It is most evident in music featuring vocals and acoustic wind instruments: things that live in the mid-range. Actually, all amplification devices have a signature sound, whether you're talking about transistors, mosfets or any other gain device. And even within the SET tube category there are characteristic traits that distinguish the 300B from the 845 tube, for example.

Remember Vaic Audio, the tube amp manufacturer famous for their beautiful, lush sound? Vaic has been reincarnated and is now part of Ayon Audio. Living Sound GmbH is the worldwide distributor for Ayon Audio. Master Sound SAS is an independent manufacturer and distributor of high-end audio products and licensed manufacturer of Ayon amplifiers, which has more than twelve years of expertise in high-end audio design and marketing. Acoustic Dreams LLC is the exclusive North and South American importer and distributor of the combined products of these companies. The current amplifier lineup starts with Master Sound and escalates to the premium Ayon line. The speaker lineup begins with the Ayon and moves up to Lumenwhite.

Previous encounters with SET tube amps left an impression of remarkable presence and intimacy coupled with some severe performance limitations at the frequency extremes and in macro dynamics. The Master Sound 845 SET mono blocks arrived together with the Ayon Signature speakers. The pairs are designed to complement each other. Does the Master Sound 845 / Ayon Signature combo evince the characteristic glories and pitfalls of SET based systems? The answer is a definitive yes…and no! Read on.

Ayon Signature Speakers

The Ayon line of speakers are made in Austria and represent the more affordable efforts of Stefan Fekete, who is also the principle designer of the Lumenwhite speaker line. The Ayon Signatures are visually unobtrusive, standing less than four feet high and only ten inches wide. The speaker's body is a black, anodized aluminum that wraps over the front, across the top, and down the back. Furniture quality natural maple wood side panels make for a sleek look from the listener's perspective. Build quality is OK, but not as good as some others at this price point. The driver complement consists of a seven inch Accuton ceramic mid-range set at eye level, a one inch Accuton ceramic tweeter above it and a seven-inch nomex kevlar Eton woofer below. The woofer is just below the mid-range driver and relatively high up from the ground. No grill is provided, so the drivers are exposed. The bass and midrange units are ported.

Two pairs of gold-plated copper binding posts are provided for bi-wiring, along with gold-plated copper jumpers, if you decide not to bi-wire. The binding posts accept spades or bananas and have oversized, knurled tightening knobs that were easy to use without the need for a tightening tool. The supplied spikes are standard issue and would be the first thing I would upgrade.

I spent many evenings over a couple of weeks voicing the speakers. The final placement was the front 16" and the rear 11" from the sidewalls, and one third of the way into the room. Toe-in was such that a slight view of the inside of the speaker was visible. This is pretty close to the usual position for my reference EgglestonWorks Rosas and that fact should not be surprising: they are both three-way, ported, floor standing designs. The sound was further tailored by adjusting the height of the spikes. Lowering the front spikes made the sound less airy and decreased treble energy, while bringing out the midrange. Bruce Fetherling, the importer of the Ayon line, mentioned this increased the sound pressure directly hitting the listener. I liked it this way: it seemed more direct, saturated and colorful. With the spikes in the reverse position -- front raised, rear lowered -- the sound became more airy and hard to localize, and also seemed kind of grey. My Argent Room Lens were placed quite close to the outside front.

Master Sound 845 Mono Amps

The Master Sound 845 Mono Amplifiers look like sporty, contemporary Italian objects d'art, which they are. The deep red, polished Cherry wood plinth is long and narrow. In the front are two small and two large mirror finished aluminum tube cages, or Tube Protectors, comprised of metal rings stacked to the height of the tubes. They remind me of a halogen lamp I once owned. Nice touches of décor that serve as heat sinks, the cages also offer protection for both tubes and humans.

If you have a frontal view when you throw the switch, the Christmas tree effect is something to behold. The big 845 tubes in their reflective cages are bright enough to read by, and then their image is reflected in a polished aluminum divider that separates the tube area of the plinth from the transformer area. Two very large black metal transformer cans occupy all the real estate on the other side of the divider. Oversize, hand wound transformers are typical on SET amps, but in this case they are REALLY big. The amp uses two 845 tubes in parallel to produce a hefty, for a SET amp, 40 watt output per channel. The output 845 tubes quickly reach 200 degrees, so give the amp 6" clearance on all sides and top. Biasing for the 845 tubes is done manually with an included meter and potentiometer screw. Two small 6SN7 tubes complete the view.

The rear panel provides three oversized, heavy-duty, screw-down binding posts: one neutral and one each for 8 or 4 ohms. I stayed with the 8-ohm taps since they sounded a bit more full than the 4 ohm, even though the Ayon speaker is specified to be 4-ohm impedance. The amp has one single ended RCA input and sits on four built-in black anodized aluminum spikes.

During installation one of the 845 tubes started to act up. Sure enough, within the first week this amp started to make loud noises indicative of a bad case of indigestion or a filament problem. I powered down and left the amps idle until the tubes could be checked and/or replaced. A couple of weeks later, Bruce came by with some replacements and since then it's been smooth sailing. These are some of the quietest amps I've come across. The transformers and tubes themselves are silent: there's none of the usual mechanical humming or buzzing. (Very little noise comes out of the speakers, either).

The 845 tubes are still being manufactured in the USA today. Apparently, they are fairly easy to make, because they retail at about $60 each, less than the cost of many common tubes, and way less than a 300B tube. I'm told they should get around 5000 hours of play. They are warranteed for 12 months or 2000 hours, whichever comes first.

Some music, please

Listening to Renee Fleming's impossibly beautiful voice on the Grammy winning CD Bel Canto [Decca 289 467 101-2] through the Master Sound 845/Ayon Signature combo, visitors were experiencing meltdown in their seats. I'm not kidding. No one could resist the allure, for something special was happening. A few people were even able to articulate the technical basis of the intimacy communicated. They claimed to be able to perceive the contribution of each part of her vocal apparatus -- chest, throat, mouth, tongue and, finally, lips -- and could visualize the mouth and lips moving to shape the sound. Now, there are plenty of amps and speakers out there that may have more detail and clarity but cannot communicate like this. There's an unmistakable quality beyond density of information that I've only heard with SET tube gear: you can hear it within five seconds. This was getting a little spooky. I sure cannot explain it.

The other unusual thing about Renee's voice is the enormous three-dimensional cushion of air surrounding her image. While good components are able to layer instruments deep into space and create a holographic soundstage, the 845/Ayon gives them individual depth as well. For example, the French horns have a discrete location defined by width and height, usually back behind the violins on the left side. Hearing the same soundstage through the 845/Ayon, the air is excited in the horizontal and vertical planes, but is also moving in the front-to-back, or depth, plane. It feels like warm air is moving all around the instruments, which is much more realistic. By comparison, the stage created by other gear seems flat, populated with two-dimensional cutouts of the instruments.

In addition to the superb reproduction of voice, the Master Sound 845/Ayon Signature combo will catch you off guard in its ability to passably do big dynamics. Track 10 of the same CD, Bellini's "Il pirata", is an excellent test of system dynamics. The French horns begin softly and, as orchestral sections make their entrance, the sound grows and grows, until you're about ready to reach for the volume control. Well, the sound grew, but I never needed to reach, as I would have with the YBA Passion 1000 mono blocks. Similarly, side one of the Classic 45 RPM re-issue of Saint-Saens Symphony #3 [LSC 2341], featuring Charles Munch and the Boston Symphony Orchestra, is a favorite for its great orchestration and dynamics. This was one of the first albums to actually claim to be "A Stereo Spectacular" on the cover. However, on peaks it overloads and doesn't swell like it does with the YBA. But let's put things in perspective: only the finest solid-state amps can handle these massive crescendos. For a SET tube amp at this price point to come reasonably close is uncommonly good behavior and I consider their performance in this area excellent.

My other surprise was the combo's seemingly unlimited treble extension and reasonable bass. You just don't expect this kind of performance from low powered SETs. So in answer to the second part of my introductory question, no, the combo does not evidence the characteristic pitfalls of the SET genre.

As for detail retrieval, some tube gear masks small events with a euphonic scrim. Although there certainly is some added euphony, the degree of smoothing going on here was minimal. While there may not be as much detail as with the YBA, micro dynamics have colors and shadings not present on the YBA. Inner voices simply bloom. Listen to Thurman Green's trombone on Dance of the Night Creatures [Mapleshade MS 06032]. At the beginning of track two, "Passion Flower", you hear him clearing his mouthpiece and moving towards center stage. After every phrase you can hear Thurman release the air pressure on the instrument's mouthpiece.

Ayon Signature Speakers

Two things are especially noteworthy about this speaker: first, the crossovers. It's obvious that intelligent choices were made regarding matching of drivers and crossover design. The drivers blend so seamlessly you can't tell which driver is active at any given time. The response curve is continuous, linear and has the same quality up and down the spectrum.

The second thing is the tweeter. Ceramic tweeters are new to me. This specimen exhibits no noticeable ceiling. It ascends to wherever the signal wants to go. Its quality is remarkable in the lack of signature, glare or hardness. Factor in its speed and a bit of sweetness. The tweeter steps aside and you kind of take its performance for granted. One thing to note: because it has no excess flesh, I could imagine it sounding a bit lean in some rigs.

The midrange driver is also ceramic and exhibits a lot of the same characteristics as the tweeter: no glare or hardness, sweet, fast, with a linear response curve and no extra flesh.

The low-end response is harder to gauge. I can't separate how much is due to the speakers versus the amps. The bottom is a little loose, warm and lightweight. The woofer put out less energy than the other drivers did. In my room, the frequency response was non-existent from about 45 Hz. The sub woofer was needed to fill in with the sub's cutoff frequency set in the area of 45 Hz, and it's volume set fairly high. I bet this was at least partly due to the Ayons not having a supporting rear wall behind them to reinforce the bass.

The Ayon Signature throws a huge sound stage with its location quite variable. Most often the stage projected from the speaker plane backwards. Sometimes it was forward sounding and became "in your face". These speakers have an airy quality. They disappeared with noticeably more sound outside and around them and less localization at the drivers. The sound floated detached from the speakers. Images were a bit larger than life size.

Sounds Like Ear Candy

The sound was warm, rich and creamy, but clear and open. Transients were a little soft, and dynamics a little polite. The response curve was linear in spite of the warmth. Smooth, very smooth, grainless to a degree well beyond any solid state amp. The telltale signs of the mechanical/electrical origins of the sound were reduced. It sounds like EAR CANDY. I found the 845/Ayon combo so inviting and enjoyable listening sessions were lasting far too long and wrecking havoc on my schedule.

Tweaks and Other Gear

I tried many products under the amp's spikes, including ART Q-Dampers and Golden Sound DH Squares. I wound up using either pennies or nothing at all. Just letting the points go into my wood floor was good too. For the Ayons spikes, try some Golden Sound DH Squares. These brought out the mid-range. Or try some copper pennies for a little more bass response.

Harmonic Tech Magic power cords sounded good, as did Golden Sound Black cords. I mostly used the HT Magic One interconnects. The Magic One controls the treble and keeps it from getting edgy, while providing plenty of low-end energy. Its mid-range is so natural it disappears. Swapping to other interconnects did not have as big an effect as I expected. Wires that I knew had colorations seemed to become more neutral. The amps seemed to fix the incoming signal.

Speaker wires had more of the expected results. The HT Magic Woofer speaker cable presented a big, wide sound stage with lots of heft and dynamics and bountiful low end. Shunyata Lyra and Kharma Grand Reference speaker cables also worked well.

Purity and accuracy were enhanced when the amps were connected to a Balanced Power Technology Model 3 power conditioner. The sound was quieter and cleaner, with more definition. The Von Gaylord Audio (formerly Legend Audio Design) Live Performance AC conditioner made the sound darker, fuller, and more mid-rangy. It was definitely more musical, with enhanced smoothness and suppleness, if a little less accurate.

Other amps I tried with the Ayon Signature speakers included the Zanden integrated tube amp and the YBA Passion 1000 solid-state mono-blocks. Neither was a good match; I suspect an impedance mismatch in both cases. The Ayon is specified at 4 ohms, while both of these amps like to see 8-ohm loads. The new darTZeel NHB-108 model one solid-state amp worked very well with the Ayon Signature. The sound was full and dynamic, but it didn't have that SET magic. (Reviews of the YBA Passion 1000 and darTZeel amps coming soon.)

Towards the end of the audition, I substituted my EgglestonWorks Rosas for the Ayon Signature speakers. I was leery of trying this combo because the Rosas 87db efficiency rating and the Master Sound 845s 40 watts didn't look very synergistic. I shouldn't have procrastinated! The Rosas sounded dark, full, rich and sweet. The low end was actually over-powering until I ran the amps through the Balanced Power Technology Model 3. Surprisingly, dynamics were actually quite good. I guess this was because of the 845's very high current and high power headroom. But the stage wasn't as wide, and there was less air than with the Ayon. Imaging was vague and unfocused. The Rosas sounded great, but more like a reproduction. They could not bring out that special quality in Renee's voice. For vocal realism and palpability, the Ayon Signature/Master Sound 845s are unmatched.

Acoustic Dreams makes their own line of fine component racks and amplifier stands. Also near the end of the audition, they sent over a pair of stands for the 845s made from hardwood maple over a 1/8" aluminum plate frame, with some dampening material, and adjustable stainless steel spikes. Build quality is excellent. When I put the stands in, the darkness and loose low end of the Rosas/Master Sound 845s disappeared. You won't believe it, and none of my visitors did, but the quality of the bass coming out of the Rosas/Master Sound 845s was now rivaling that of very good solid state. The hazy soundstage clarified and images became stable. The sound was very smooth. Artifacts that I didn't even know were present were removed. The stands are a mandatory accessory. MSRP is $720 a pair.

Conclusion

No doubt you've noticed throughout this review that I'm comparing the Master Sound 845 amps to the YBA Passion 1000s. This is because comparison to other tube amps I'm acquainted with would be futile. The Master Sound 845s are the finest tube amps I've encountered. Putting them up against the YBA 1000s, which is the finest solid-state amp I know of, is paying them the highest compliment.

The combo of Ayon Signature speakers and Master Sound 845 amps clicked in a big way in my 12' by 31' by 8' ceiling room. The sound was beautiful. That well-known SET ability to communicate emotion was present in spades. Regardless of whether there were system issues present, listeners felt touched by the musical message. Classical music and especially opera aficionados will find magic in this combo. Just marry the light bass to a powered sub to get some good slam and weight in the lower regions.

While not inexpensive, the Master Sound 845 amps and Ayon Signature speakers together reproduce music so compellingly that you might find yourself agreeing with Clement Perry: "The game is over, pal. That's my sound."