I’ve reviewed my fair share of amplifiers and integrated amplifiers that employ the 300B triode vacuum tube in the output stage.
These include the Triode Evolution 300 Integrated Amplifier (review), BorderPatrol S20EXD Parallel Single-Ended Amplifier (review), and the Feliks Audio Arioso 300B Integrated Amplifier (review). I used to own a lovely Sun Audio SV-300BE and regular readers know there are three 300B amps in for review—the Qualiton 300B Integrated Amplifier, Audio Note Meishu Phono 300B Konzertmeister Integrated Amplifier (more info), and the Treehaus Audiolab 300B-2 SET Amplifier along with The Preamplifier (more info). You could say I’m steeped in 300Bs.
As is the case with most things hifi, all 300B-based amps do not sound the same just like ladder DACs and horn speakers. Heck, different 300B tubes sound different from one another so it’s no wonder some people like the comfort of believing, as a matter of faith, that all 300B amplifiers sound the same even though they don’t.
The Audio Hungary Qualiton 300B Integrated Amplifier uses four 300Bs, two per channel, run in push-pull configuration for a total of 25 Watts per channel while the preamp and driver stages rely on pairs of 12AX7s and 12AT7s per side. All tubes are new stock Electro-Harmonix.
From Audio Hungary:
At Qualiton, we adhere to a pragmatic approach in tube amplifier design. We believe that a truly exceptional amplifier should:
- Be compatible with a wide range of loudspeakers.
- Exhibit a Total Harmonic Distortion (THD) of less than 0.5% across the entire power spectrum, from milliwatts to rated power, spanning 20 Hz to 20 kHz.
- Maintain a flat THD vs. Frequency plot when measured at a fixed output power.
- Deliver fast and controlled transients throughout the audio range, which goes hand in hand ith the frequency response being wide and flat.
- Operate at low noise levels with an exceptional signal-to-noise ratio.
- Combine thoughtful design, robust technical parameters, and exceptional sound quality.
In the preamplifier and driver sections, the 12AX7 and 12AT7 tubes play a crucial role in achieving these goals. Furthermore, their DC-stabilized filament supply and circuits with low offset and stable DC operating points ensure resilience against parameter variations.
I know you know, but a typical 300B SET amp with just one pair in play typically produce around 8 Watts of output power so the Qualiton’s 25W is what makes it “compatible with a wide[r] range of loudspeakers.” It’s also worth noting that Watts alone don’t tell you all you need to know about mating an amp with a speaker and experience suggests that nothing you can read on a spec sheet can. As uncomfortable as it may be for some to hear, listening is the best path to knowledge when it comes to building a hifi system that’s meant to play music in such a way as it makes us focus on just that.
Around back reside a total of five inputs using precision, low-power, ultra-miniature Japanese relays with ultra-low contact resistance gold overlay silver contacts, all of which are controlled by a microprocessor. Inputs include 1x XLR and 4x RCA joined by a Sub Out and a pair of speaker outputs with 4 and 8 Ohms options, an IEC inlet, and power switch.
The Qualiton 300B employs an automatic bias system (so you don’t have to). From Qualiton:
This circuit continuously monitors the behavior of each tube and regulates the bias voltages accordingly, ensuring the smallest possible output voltage noise while guaranteeing the highest degree of linearity of the output stage. Additionally, it prevents the sensitive, high-permeability output transformer cores from saturating by precisely equalizing the quiescent currents of the power tubes.
The front panel is self-explanatory and simple—one multi-function knob dead center with the Qualiton logo and a scratch-resistant smoked plexiglass display. That display shows amp status during warm-up, volume level, and the input when changing inputs. The display brightness gets brighter when in use and automatically returns to the selected brightness level after 10 seconds. Nice.
The included remote offers the same functions as the multi-function knob and adds Display Brightness Level by pressing and holding the Mute button and selecting one of three levels. The relay-controlled volume uses a 100-step relay-controlled stereo attenuator featuring 25 microprocessor-controlled signal relays that switch a total of 48 precision metal film resistors.
A protective tube cage is included but I prefer the Qualiton 300B without because I enjoy looking at the light show, especially at night. It’s worth noting that the Qualiton weighs in at about 60 lbs. and a good chunk of that weight comes from the in-house designed and manufactured custom output and power transformers hidden inside.
From Qualiton:
The transformers of our amplifiers are custom-designed and built in our in-house transformer workshop. Our output transformers are constructed using high-permeability, large cross-section toroidal magnetic cores, which undergo initial impregnation during the production process. Following this, the winding process begins, utilizing a multi-layered, sectioned, and specially arranged winding configuration. This meticulous design ensures optimal performance across both low and high frequencies. Once the winding is complete, the transformers are encased in metal shielding cans to minimize electromagnetic interference. Finally, they are potted using an epoxy compound to eliminate mechanical vibrations and associated noises.
The Qualiton 300B spent some time driving the review DeVore O/Bronze (more info) on the Barn’s B-Side and most of the time paired with the review Ø Audo Verdande (more info) on the A-Side. Front ends included the review Weiss Helios streaming DAC (more info), the Barn resident Grimm MU1 (review)/totaldac d1-unity (review) combo, as well as the totaldac d1-CD Transport & d1-streamer-live (more info) paired with the d1-unity. All very (very) good digital with cables from AudioQuest wiring both systems (see full system and Barn details).
The Ø Audo Verdande and their 94dB sensitivity, 26hz-20khz claimed frequency range, and 8 Ohm impedance made for my favorite Qualiton 300B mate. This system with the Grimm/totaldac and all totaldac front ends offered the best combination for the Qualiton so the following listening notes are all based on this combo.
Birthmarks by Bambara was released back in March on Wharf Cat Records and the Brooklyn-based, Athens, Georgia born band reminds me 1980’s bands like Crime & the City Solution with their moody gothic drama. The core band consists of twin brothers Reid Bateh (lead vocals, guitar) and Blaze Bateh (drums) with William Brookshire on bass but they’re joined by a host of guests on vocals, organ, alto sax, vibraphone, viola, violin, trumpet, and harp. Think big music, big drama which is a perfect recipe for the strengths exhibited but Qualiton 300B/Verdande combo.
Pounding drums and big fat bass lines form the foundation over which the more subtle sounds and dramas unfold and the Qualiton excelled at making that foundation feel rock solid and physically present. There’s nothing loose or flabby about this 300B integrated, come to think of it most of the 300B-based amps I’ve heard aren’t. If anything, the Qualiton comes across as a powerful and refined with real dynamic slam coupled with a nice sense of tone and color, albeit a bit more restrained than the much more costly Audio Note Konzertmeister which offers a truly psychedelic experience (the good trip kind).
Wet Leg’s latest, moisturizer, is their high water mark so far as far as I’m concerned with all of its coy badass-ness. Rhian Teasdale is out front backed by guitarist and co-writer Hester Chambers along with guitarist Joshua Mobaraki, bassist Ellis Durand, and drummer Henry Holmes and together they make a damn fine racket. This is another driving sound of a record seemingly made to highlight this Qualiton/Ø Audio pairing. Perfectly punchy and equally adept at reproducing the finer details amid the fury, the Qualiton 300B proves itself powerful enough to raise the Barn roof with 90+dB peaks of Wet Leg passion without breaking a sweat all the while giving Teasdale’s voice with all of its character and inflections vividness and form out front. Nice.
Lucinda Chua’s 2023 debut album YIAN finds the London-based cellist and composer exploring her split worlds. From the liner notes:
“YIAN” (燕), means swallow in Chinese, and is part of “Siew Yian,” the name given to Chua by her parents to preserve her connection with her Chinese heritage. Just as the migratory songbird lives between places, so did Chua, the artist living in the in-between of the English, Malaysian and Chinese cultures that make up her heritage. In the absence of Mandarin as a mother tongue, music became a way to express the parts of herself that couldn’t be described in words; “YIAN” emerged as a way to heal.
This is delicate music with Chua’s gentle vocals out front supported by strings, electronic swells, and other voices and the Qualiton showed off its delicate side by highlighting the tactile goodness of these varied voices pulsing through the Verdande with intimate presence. While I’ve heard a greater sense of dimensionality imparted to each voice as well as a larger and airier sound image, the overall presentation offered by the Qualiton/Verdande pairing reached deep into the sounds and forms of YIAN making for a just ripe enough sound world to explore.
The Qualiton 300B costs a fraction of the Audio Note Konzertmeister’s $67k asking price and is also substantially less than the Treehaus 300B-2 SET Amplifier at $30k so it’s pointless to make direct comparisons except to point out that these costlier amps provide a richer, deeper experience according to my tastes. The recently reviewed Aesthetic Mimas (review) is more in line, price-wise, at $11k and in terms of a perfect partner for the Verdande, my preference leans toward the Mimas for its greater control, especially with deep bass, and superb resolution. The Qualiton’s presentation offers more overall weight, a kind of robustness, that some listeners might find more energetic and engaging especially on poorly recorded music.
The Barn resident Leben CS 600X, especially with its recent NOS tube upgrade, at $9,995 makes for another interesting comparison. I preferred the Leben on the DeVore O/Bronze for its rich robust and well-controlled sound. By comparison, the Qualiton sounded bigger but with the O/Bronze it also added a bit too much stridency and upper frequency hardness for my tastes. With the Ø Audo Verdande, it was much closer in terms of a favorite with the Leben delivering a tighter and brighter sound, while the Qualiton tilted the overall presentation towards body and weight. Horses for courses.
On paper, the push pull Qualiton 300B should have no trouble driving the 96 dB/W/M/12 Ohm O/Bronze and while the it did offer more than enough power, this combination did not get the best from the amp or the speakers. For my tastes, the Qualiton made the O/Bronze sound a bit anemic and a touch too hard up top, sonic qualities that are not inherent in these speakers or in the Qualiton amp. I did spend a few days listening through albums and favorite test tracks but was never able to fully immerse in the music as the sounds of reproduction proved too distracting.
I closed out my time with the Qualiton 300B driving the Ø Audo Verdande with an old favorite, the self titled Lonely Guest from Tricky (as producer) and a wonderful cast of characters on vocals giving different flavors to each track that share an underlying tricked-out groove. This music through this system hit all my sweet spots with plenty of color, character, and drive pumping up the weight and funk to smile-inducing heights.
The Audio Hungary Qualiton 300B Integrated Amplifier provides enough power to drive most speakers with a sensible load while giving a good taste of the richness the venerable 300B triode has to offer. The Qualiton imbues music with a very nice sense of weight, control, and vividness that in the right system delivers a compelling musical experience.
Qualiton 300B Integrated Amplifier
Price: $11,000
Company Website: Qualiton
US Distributor Website: Well Pleased A/V
Specifications
Electrical
Rated Output Power: 2 x 25 Watts @ 4 or 8 Ohms
Output Load Impedance: 4 or 8 Ohms
Number of Channels: 2
Frequency Response: 5 Hz – 85 kHz (-3 dB, 1 Watt) |15 Hz – 70 kHz (-3 dB, 25 Watts)
Total Harmonic Distortion: < 0.5 % across the entire power spectrum, from milliwatts to rated output, spanning 20 Hz to 20 kHz.
Rated Power Bandwidth: 20 Hz – 20 kHz
Signal-to-Noise Ratio: > 105 dB below rated output | 20 Hz – 22 kHz bandwidth, without weighting filter > 110 dB below rated output
with A-weighting filter
Number of Outputs: 2 Unbalanced POWER OUT, 1 Unbalanced SUB OUT
Number of Inputs: 4 Unbalanced STEREO IN, 1 Balanced STEREO IN
Input Sensitivity (for rated output): 0.65 Volts Unbalanced | 0.65 Volts Balanced
Input Impedance: 10 000 Ohms Unbalanced | 20 000 Ohms Balanced
Gain: +23.75 dB @ 4 Ohms | +26.75 dB @ 8 Ohms
General
Vacuum Tubes: 2 x 12AX7EH Gold, 4 x 12AT7EH Gold, 4 x 300B EH
Remote Control: Stand-By, Volume, Mute, Input Selection, Status Display Brightness
Power Requirement: 200 W idle | 460 W max | 1 W stand-by
Weight: 28 kg
Dimensions: 42.5 x 50 x 21 cm