AricAudio Super 300B SET Amplifier by Terry London

A Combo of Sonic Delights

In 2017, I wrote an article entitled, “What’s So Irresistible About a SET (single ended triode) Amplifier?” that explained the allure of the 300B flea watt approach to amplification. A 300B tube SET amplifier can only deliver around 8 to 10 watts per channel. However, the purity of tonality and color, an effortless liquidity/ease, an enchanting holographic dimensionality in the mid-band, and finally, a subjective experience that brings you closer to the emotion of the music is quite enchanting. This combination of sonic attributes creates for the listener a sonic bliss more often than other great tube or solid-state designs. There is a significant CAVEAT that goes along with getting a 300B SET amplifier to perform to this level. The speakers it is driving better be at least 90dB efficient and the nominal impedance around 6 ohms or higher. Luckily, for this review of the 300B based AricAudio Super 300B SET, I had the perfect “dance partner,” the Role Audio Starship S.E. loudspeaker. It was on the 2020 Stereo Times MOST WANTED COMPONENTS list and has a sensitivity of 93dB at 1/watt/m and a minimum impedance of 10 ohms. It turned out to be a beautiful match for the AricAudio Super 300B SET amplifier. 

As I have stated in my other reviews of AricAudio’s tube-based preamplifiers and power amplifiers from this small artisan company, owned by builder/designer Aric Kimball, which is located on the East Coast, offers high-level build quality, reference level performance, bar none, creative design topographies, and reasonably priced tube-based gear found on the market today. One of my greatest regrets as a music lover and reviewer is that I did not purchase Aric’s Super 211 SET amplifier after reviewing it for 6 Moons. It was one of the finest amplifiers I have ever had in my system. Well, don’t weep for me; as you will see later in the review, his new revised Super 300B SET amplifier, which retails for $5575, has, for my tastes, superseded the 211 tube-based amplifier, and this time it’s not leaving my home! 

About the same time that I arranged the review on this amplifier, I was also able to set up a review on the very highly regarded Western Electric 300B tube, which is currently manufactured in Rossville, Georgia that is the updated version of the legendary Western Electric 300B tube first created in 1938. Suppose you can still score a pair of NOS 1930’s/40’s Western Electric 300B tubes they sell for $8000 to $20,000 a pair, without any warranty, of course. The Western Electric company that manufactures the new stock WE 300B started in 1995, bought the rights to the brand name, is identical both in the glass enclosure/bulb and internally replicates the original circuit (it also has a special composite graphene structure that’s a trade secret and only used by Western Electric). The owners also bought some of the original machines used to produce the NOS WE 300B tubes way back in the day. A matched pair costs $1499. Even though the 300B is a very sturdy and long-lived tube, at least 15000 hours if driven correctly, the Western Electric 300B tube comes with a five-year warranty. For more information and history regarding the 300B tube and who started it, I suggest visiting their website. The wooden box and packaging, the data spec sheets, and how these magnificent-looking tubes were shipped were all first-rate and speak of the care that this company has for delivering and presenting their product.

The AricAudio Super 300B SET amplifier is a two-chassis design. My review sample was housed in a beautifully constructed three-color (wood inlay) chassis. The power supply weighs over thirty-five pounds. On the front of the chassis that houses the 300B tubes is a pair of blue light meters that show the biasing of the 300B tubes. Two very high-quality modified speaker connectors attach the power supply to the tube chassis. One of them, a 4-pin connector, delivers each 300B with its well-filtered filament voltage. Around the back of the 300B tube chassis are high-quality 4-Ohm/8-Ohm speaker wire connections. The inputs for the amplifier are located on the back of the top plate. The power supply uses dual 5U4 G.B. rectifiers and avoids the switching noise associated with solid-state rectifiers. Flanking the dual rectifiers is a pair of OA3 gas-charged regulators that regulate the B+ to the 6SN7 driver tubes. There are a total of six transformers used in this amplifier. The power ON/OFF switch is located on the top front of the power supply.

I have had, over the years, at least three reference level 300B SET amplifiers that gave me great pleasure listening to music in my different systems. However, regardless of which brand of 300B tube was used, they had the following minor shortcomings. First, they were slightly rolled off in the high-end frequencies and tended to have a touch of being muddy in the lower bass. The AricAudio Super 300B SET amplifier was linear top to bottom, with sparkly detailed highs and taught powerful bottom end. I asked Aric to share what he did in the Super 300B SET design to eliminate these shortcomings.

“Many audiophiles believe the 300B to have a wonderful midrange, but a rolled off high-end and a wooly bass- and there not wrong. The 300B is known for its excellent, robust midrange. However, the rolled-off highs and lackluster lows are due to the tubes driving the 300B. The 300B, like all other DHT’s (directly-headed triodes), draws grid current and has a fair amount of capacitance at its grid. So, what happens is the grid draws more current than the driver tube can deliver (especially in the case of capacitor-coupled drivers), and the sound ‘slews’ and suffers at the frequency extremes.

In the Super 300B SET, I only use 6SN7 tubes as the input amplifier where it remains very linear and simply provides the gain for the driver. The driver is a triode-strapped 6V6 pentode, which is extremely linear when run as a triode and has a nice low output impedance of around 1,500 ohms. It can easily drive an inter-stage transformer, which in turn drives the 300B’s with ease. With a stout driver capable of delivering around 20MA, there is no slewing, and the 300B’s miller capacitance does not make the driver suffer. The end result is an extended, accurate, and transparent top end and a deep, taut, and extended low end. Of course, the midrange richness is left untouched, so the net result is an amplifier with an accurate frequency response and plenty of dynamic power. This does not put any additional strain on the 300B, and it is able to provide 10 watts per channel.

The rest of the amplifier is over-built with multiple chokes and lifetime-rated film capacitors in the power supply. All filaments and heaters are run in D.C. with ultra-fast recovery diodes used throughout. I believe the sum of these parts creates an amplifier that excels in making the 300B tube shine the way it was intended back when it was the preferred “theater” amplifier tube.”

When I played the album, In & Out by my all-time favorite tenor saxophonist, Johnny Griffin, and French pianist Martial Solal (who is still active at 94), I was mesmerized by two aspects of the music through the AricAudio Super 300B SET amplifier. First, the crystalline purity of Griffin’s tenor saxophone timbres was so beautiful and natural sounding that it gave me the “chills” that I would experience when I heard in person. Secondly, the lower register of Solal’s piano bass pedal notes had a dynamic impact that I could feel viscerally, along with an outstanding articulation and clarity of these lower frequencies as they flowed effortlessly into my listening space.

The next album up was Golden Child, the very well recorded studio session by Jared Gold, one of the current generation’s most innovative Hammond B3 organ players. His trio has the great Ed Cherry on guitar and the explosive drummer Quincy Davis. Everything from total funk to gut blues and mainstream hard bop is all played in a hard-hitting swinging and melodic manner that raises your energy/fun level to a high degree. Everything, from the bass notes of Gold’s B3 organ pedals to the explosive cymbal shots and drum rolls of Davis, to the delicacy of the micro-details and sweet timbres of Cherry’s guitar runs, was captured by the Super 300B amplifier with the highest resolution without ever sounding analytical and maintaining overall effortless liquidity that brought me easily into the pulse and emotion of this music’s excitement and fun factor. 

Of course, I had to try a vocal to evaluate how the AricAudio Super 300B SET amplifier would render the beauty of the human voice. I chose Jacintha’s album, Fire & Rain, which is her jazz tribute to the compositions of James Taylor. It is exceptionally well-recorded by Groove Note, and her backup musicians are first-rate studio greats such as drummer Russ Kunkel and Leland Sklar on bass. The illusion that Jacintha was actually in my room performing was based on three qualities that this amplifier was producing. A holographic image of Jacintha sitting in the middle of her band. There was a sense of air around each instrument and the space between them that brought me into the recording venue. Finally, her voice’s gorgeous colors and tonality were captured in a natural/lifelike fashion.

All of the above musical experiences and how the AricAudio Super 300B SET amplifier performed were used in Western Electric 300B tubes. However, I extensively evaluated other highly regarded 300B tubes to gain a perspective on how the Western Electric 300B tubes ranked in their performance in the Super 300B SET amplifier. The four other 300B tubes used in this process were: Elrog ER300b, Sophia Electric 300B Royal Princess, Emission Labs 300B-XLS, and Shuguang Treasure 300B-Z.

Unequivocally, the Western Electric 300B tubes were superior in the following categories. They produced the most linear presentation from the highest frequencies to the lowest frequencies. The top-end had an overall aliveness/shimmer that gave life to the music much more so than the other companies’ 300B tubes. The low-end tautness, extension, and speed were noticeably better than the other 300B tubes. The color/timbres of the mid-band were more vivid and engaging. Finally, the Western Electric 300B tubes created a more overall three-dimensional/holographic sense of spatial dimensions than the other 300B tubes. They allowed me to be more easily captivated by the beauty and emotionality of the music.

I titled this review A Combo of Sonic Delights. After reading the above details, I hope you understand why this title fits the AricAudio Super 300B SET amplifier, tubed with the Western Electric 300B matched pair of tubes. Both are first-rate, beautifully built products. The AricAudio Super 300B SET amplifier, based on its performance regarding tonality, extension/linear range, overall image palpability, and spatial qualities, is the most exemplary 300B SET amplifier I have ever had in-house. It indeed is not inexpensive but competes with other SET amplifiers costing thousands of dollars more. The Western Electric 300B tubes are the best sounding 300B’s I have heard in my system. I also believe that they are somewhat a bargain at their price point, particularly when you add that they come with a five-year warranty, which is a much longer time period than any other 300B tube on today’s market. So, you can see why I’m purchasing this Combo of Sonic Delights! If you own speakers that will correctly match up with a 300B SET amplifier, I highly recommend both of these great products to you for a beautiful music experience. 

  terry london     

Specifications:

  – 9 watts RMS per channel

  – 5-50,000 hz frequency response

  – 100kOhm input impedance

  – 1.5 volt input sensitivity (can be used without a preamplifier if using a high voltage source with a volume control

  – weight: 60 lbs

  – dimensions: 16″ x 12″ x 6″

  – includes Genalex Gold Lion 300B (x2)

  – includes E.H. 6V6 (x2)

  – includes Tung Sol 6SN7 (x2)

  – includes Watt-Gate terminated power cable

  – includes custom-made power umbilical cables (x2)

  – 100% point to point wired

  – No active regulators or chips used- pure analog design

  – 3-4 weeks to build

  – 2 year warranty

Address:

Aric Audio Systems

32 River Street

Palm, MA 01069

Tel. 413-627-2543

Contact:  https://aricaudio.com/contact.php

Website: www.aricaudio.com

TJ’s Associated Equipment

Sources:

Audio Note U.K. Balanced 3.1 DAC MKII

Pass Labs DAC-1

CEC Transport -3

Project reference transport & LTA power supply

Amplification:

Coda 07x preamplifier

SPL Elector preamplifier

AricAudio ML-MKII preamplifier

Coda #16 amplifier

Threshold 550e amplifier

AricAudio Super 300B SET amplifier

SPL S800 amplifier

Loudspeakers:

NSMT Model 100 

Tekton Design Ulfberth & Perfect SET

NSMT bandwidth active subwoofers

Martin Logan reference subwoofers

Accessories:

Full loom Black Cat Cables Digit 110 AES/EBU-3202 XLR interconnects

Kirmuss Audio Adrenaline speaker wire

Krolo Design Rack & footers

Puritan Audio Laboratories PSM 156 Studio Master- Ground Master-City Master- Route Master

Audio Archon power cords