The Tektron One TK 211-I integrated Amplifier review


Well-Known Member
Apr 24, 2014
The product: SET based on the famed 211 tube.
Power: 16WPC
Tubes: 2X12AU7/2X211i, Bias setting is automatic
Dimensions: 42X28X25 cm
Weight: 30kg
Options: Wood finishes, remote control
Prices: Check the link and contact the dealer


+ Palpability - like having the musicians in your house

+ Voices and instruments just float out and grab you

+ Timbre and texture - just spot on

+ Not just about bloom - good speed too

+ Not just the midrange


- Relatively forward sounding (not bright) - hence you need to get used to having a band at home all the time

- Loud passages, badly recorded music can get too much (because of forward sounding)

- Incredibly hot

- Looks can be polarising (sign of the times) and heavy

When Aernoud of Audio Note asked me whether I would like to listen and write about the Tektron One 211i SET amplifier, I decided to play cool and say "let me look at my schedule", hiding the giddy excitement that I am sure that my daughter felt before her first Justin Bieber concert.

SET Amp (Single Ended Triode, a configuration where the valve amplifies the entire waveform, rather than push pull where a pair of valves are used in complement)! It always invokes magic with audio lovers. Some reject it outright because the next words you see are low power. However, this one was 16WPC, plenty enough for my Graham I knew from experience (the Graham and Leben 300xs worked very well). And a tube that graced many a great amplifier - the Ongaku amplifier included. Known for its linearity and initially developed for transmitting radio signals, this Direct Heated Triode (another holy aspiration) is used in zero feedback designs. Googling suggests to get the best of a SET, the designer needs to put in a lot of work into the power and output transformers - more than most designs - which makes this amplifier a weight lifter's dream.

Note from the link that this amp is made with many different tubes – EL34, 300b, 2A3, 45, KT 120, KT150, KT 88 among a few. They all come at different prices and output power. Choose your flavour and your pocket’s favour, and off you go. Bias setting is automatic, and so less to fidlle with.

Getting the amp: Drove down to Aernoud's place with my well buffed driver Rupesh. First came the cage (methacrylate) and then came the tube amp to the car. When I saw the giant tubes, I thought "Oh yes, come to daddy". Reached home, tried to carry it up and then swallowed my ego and gave it to Rupesh (a bit lopsided in weight distribution due to the transformers). I carried the cage.

My wife's response was "What? No!". Giant tubes sticking out like in the older Star Wars or Dunes movies. The methacrylate cage is translucent, and is not as impressive as say the Leben's metal mesh cage. However, that changed when she listened to the sound.

The rest of the amp was beautifully finished, copper and black. The knobs and connectors felt solid and of a good quality. The volume control and input selector for example felt very good.

Switching it on and playing: Decided to keep it simple. Mac with Tidal/JRiver wav files - Oyaide cable - RAL RATOC Dac (am I the only one in the world to have it?) - Mogami Cables - Amp - Oyaide Across Speaker Cable - Graham 5/9. Power cables with Audience. And of course, my a-bit-too-live room. Comparisons were made by switching over to the Norma IPA 140 integrated.

The tubes used were Psvane 211 and Tung Sol 12AU7. If you buy the amp in India, random tube rolling invalidates the warranty - you need to buy the tubes from Aernoud who measures them and makes sure that they measure well. Now that may be regarded as a bummer (could not think of a different word), but remember that Aernoud also stands by the product with his warranty.

The tubes light up really bright, and over a period of time, get insanely warm. In fact, I think it created the low pressure zone that brought the monsoons back to Bombay. The height of the amp with the tubes is ~27 cm from the base, and so be careful where you keep it. I kept it on top of the rack.

Listening: I listened to a wide variety of music over a period of days, either using TIDAL or using wav files on JRiver (latter was better). All were 16/44. On Day 1, I played pop (my Britney phase, Tyler The Creator, Kanye West, Shabazz Palaces), much of it through TIDAL. The first impression is wow. Everything is very present and palpable. Every detail was there and big. When you listened to the chorus in "Dark Fantasy", it was breath-taking. And Kanye's voice and beats kept the foot tapping.

Skipping over to Classical on Jriver another day, the piano sounded a bit clangy initially (a nod to my pal - this is Schumann-Schubert Sonata For Arpeggione / Schumann: Fantasiestücke Op. 73 with Margerich on piano and Maisky and cello), but in about 45 minutes (I think the warm up times are long), everything turned more liquid - later in the evening listened to the same album, and the difference was easy to spot.

The midrange was brilliant - all voices - male and female - single and chorus were spellbinding. Play Carmen (Callas/Pretre), and the voices laterally in the stage are just incredible. You can see the chorus as many voices so clearly. Play Duke Ellington's "Such Sweet Thunder", and each instrument was alive with outstanding texture. For example, the harmonies created by various wind instruments were so easy to spot, with each sounding real in its space - the open sounding brass, the relatively rounded sound of the sax - you could virtually visualise it. I could have invited the players for a drink. I think it’s the best I have heard this album.

The treble was excellent too - no unnecessary emphasis, but enough sparkle . The piccolo flute (Stravinsky The Rite of Springs - Gergiev) came across very well (better when warmed up). The bass was warm and tactile, but did not have the gut hitting punch of even my Clones 55pm, leave alone the higher power Norma (when I listened to Aphex Twins, T69 Collapse).

The transparency was also very good in both a natural and a hifi way. Not only was the tap tapping of the drummer in Babylon Sisters (Steely Dan Gaucho) so easy to follow, but the musicians breathing in Schubert-Schumann, the pizzicato (plucked strings on violin or cello all came out so well.

The macro-dynamics were handled well- soft to loud was well accentuated, especially in classical music, and well represented (you won't be running for the volume knobs constantly). Bizarrely, unlike my Elekit-Clones or Norma, the room effect was reduced. I could sit further out into the room, and that we see possibly why in the next para.

Now for the caveats (a nod to Zero Fidelity, a website I like). The amp was forward sounding in my system. The musicians in the room means that you were constantly overworked to keep up with the music. Is that a complaint? In a way, yes. Listening to music while having dinner - forget it! It is much like a live concert. In Steely Dan's Gaucho, the song Gaucho could have been a little more laid back.

Not so well recorded pop was not smoothed over, equally some parts were smoothed over a tad (eg. the sound of the bow on the strings in Schubert Schumann)Loud parts of classical music could get too in your face. Strangely, in piano trios (Mendelssohn, Beau Arts, the Andante in Trio 1 is a super favourite of mine), where I expect this to shine more, all instruments being forward was at times overwhelming.

On the other hand, I also think that my relatively noisy and live room played a role. I ended up turning it higher than I should have (but in no case was the volume knob more than 12 o clock). Repositioning of the speakers (a bit more out in my room, and angled as an equilateral triangle0 also helped a lot in pushing the sound from forward rows to a few rows back, but without losing the excitement. So all the small things become very critical, as you can expect with a high quality amplifier.

When my friend TSB was over, we listened to this and then switched over to the Norma. The sound was more relaxing and you could hear the hall better. We also had to pull the chair closer to the speaker to remove the room effect and because the soundstage had moved backwards. Bass had a better solid state grip, punchier. The flip side was that the music lost some degree of vitality and presence. The Norma was definitely not as fast as the Tektron or tonally as exciting, but it's mid hall perspective was seductive in its own way. Choices, choices!

And in the end? The mid-front hall perspective of the Tektron has its amazing charms. If you try another amplifier after, like I did, you will for sure miss this amp - like the musicians packed up and went away. With different tubes, some amount of tuning the sound can also surely be done, and I am sure Aernoud will help with that.

I loved my time with it. Many thanks Aernoud for letting me experience the magic of this amp. For the price list and how to buy, I have given the link to the website - check with them for the prices.

And this amp begs the questions - do my children really need to get an expensive education or shall I buy a SET?

A question though. Since these are low powered amps, will they only sound this good only with a certain few high sensitivity speakers or can they be used with say a Kef R/Reference series or say a Quad Z series and similar such speakers. Just curious to know.
SUPERBLY written review.

Very Entertaining read.

Thank you. I had a lot fun listening and writing.
A question though. Since these are low powered amps, will they only sound this good only with a certain few high sensitivity speakers or can they be used with say a Kef R/Reference series or say a Quad Z series and similar such speakers. Just curious to know.

The specs of my LS5/9 are 87dB efficiency and reasonably high impedance. These drove them well - both in volume and dynamic swings. Aernoud himself does not recommend any lower in power amp with my speakers.
The Jinro is almost 4 times more expensive than the Tektron 211 :) I will be surprised if he has a Jinro in his showroom.
The Jinro is almost 4 times more expensive than the Tektron 211 :) I will be surprised if he has a Jinro in his showroom.

He was talking about getting one for demo a while back. I’m sure Vivek’s way with words can get him to succumb :)
We will have floods like in Germany because of global warming!

Thank you all for your kind words.
Such a beautifully written review. Your observations very much reflect mine when I moved to a Lyric audio 20 W SET. There is something so beguiling about a well designed tube amp running single ended. I have never a 211 based amp though.
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