Something altogether unexpected

Analog Ethos 2A3 stereo amplifier

2A3 Single-Ended Triode

HiFi Stereo Tube Amplifier Kit

3.5W per channel

Also available as a fully-assembled amplifier


Something Tookish may wake up inside you, and you’ll wish to see and hear things you haven’t before, and feel warmth on your face, and power a filament instead of a microchip. Introducing the Analog Ethos Legendarium, a hand-crafted high fidelity single-ended triode (SET) amplifier using the 2A3 vacuum tube. 

A classic 2A3 SET amp

The 2A3 is a directly heated triode and has a long and proven history as a high fidelity audio amplifier tube. Single-ended triode (SET) designs such as this one are found by many to provide the most authentic tube amplification. There are other excellent tubes for SET designs, such as the 300B and the 45, but the affordability and accessibility of the 2A3, combined with its excellent sound characteristics, makes this an outstanding choice for a classic tube amplifier.

At approximately 3.5 watts per channel, you may find the quality of sound and elegance of design to be something entirely unexpected. This is not a high powered amplifier, and efficient speakers (ideally above 90 dB SPL) are recommended for the best sound, though you can certainly use the amplifier with any 8 ohm impedance speakers. (Custom orders may be accepted for other speaker impedances.)

If you aren't sure if a directly heated triode amp is right for you, you may want to read my page, Help Me Choose.

Everything you need for the journey

The kit comes with everything you need to have the same quality and results from my fully assembled Legendarium amplifier. All you need are a few hand tools for assembly, and a soldering iron and basic soldering skills. Components have been carefully selected and tested to be high quality, without excessive cost. Transformers are made in USA and Canada, high grade Clarity Cap coupling capacitors made in Britain, and reliable new production tubes from JJ, Sovtek or Electro-Harmonix.

Kits come with extensive instructions, illustrations and a full explanation of the circuit so you truly learn how a tube amplifier works. You will not find instructions of this level with any other kit. 

Performance that matters

Design and part selection are based on what matters most, with an elegant circuit and relatively few components in the signal path.

The Legendarium uses a compound driver stage (SRPP design) using two 12AY7 tubes for low harmonic distortion, and single-ended triode 2A3 output with no global negative feedback. It is tube rectified to be most authentic to original designs. Hum potentiometers are included to optimize each individual tube's AC filament supply to cancel hum, and a large 10H choke is used for filtering a clean power supply for amplification. 

Maximum Power Output:  3.5W

Input Sensitivity:  1.4V

THD at 1W:  1%

Output Impedance:  8 ohms

Frequency Response:  25Hz - 20kHz (~1dB)

Dimensions:  11.5" wide x 13.5" deep (not including knob and connectors) x 9.5" high with tubes

Hand-crafted, Unmatched

Part of my intended ethos is to provide an amplifier that not only sounds outstanding, but looks beautiful as a showpiece in your home, The chassis and components are custom designed to fit perfectly and look amazing in your listening environment. Meticulous design, authentic hand-crafted construction with aluminum, hardwood and finishes. It is true analog inside and out.

Available in Ember Red, Nazgul Black, and Tower Oak finishes. Whether you choose to build it yourself or order it fully assembled, the Legendarium's individualized, hand-crafted approach allows personalized care, attention to detail and service not possible from mass-produced products. You will feel the love with every song you play! 

There is nothing like looking, if you want to find something


Customer from Florida


If you’re looking for a nice directly heated triode amp, you could buy the Legendarium assembled and be done. It’s first-rate. Both subjective opinions, but I think it looks amazing and sounds even better. But you’d be missing out.

More than a kit, Perry has put together an opportunity to learn about tubes and tube amps. Some other kits have instructions that read like Ikea directions - connect A to B, etc. The manual that comes with the Legendarium kit is divided at the highest level into two parts: How and Why. I read them out of order, as suggested. The Why part, section 2, leads to an enjoyable understanding of how tubes and their supporting circuits produce music. I have seven DIY amps behind me, but I’m new to building tube amps. After the building the Legendarium, I think I have a good foundation for understanding this formerly mysterious (to me) audio technology. I’ve been able to ask better questions, better understand other material, and think about the nuances of different kinds of tubes in a more concrete way. The kind of insight one gets from from this makes listening all the better: more engaging, more active.

Briefly, the kit parts are great - no worries here. Perry entertained all my questions before buying and, as expected, I found everything in the kit to be top-notch. There was nothing I thought I should swap out. I built my amp straight out of the box, so to speak. Speaking of unboxing the kit, it’s worth noting that I don’t think I’ve ever seen a better packaged anything. Double-boxed, bubble-wrapped, everything nestled in its place. Packed with care is what I thought when I was unpacking it. And indeed, there were no issues related to shipping. Once I had my kit unpacked, I found the build experience to be as straight-forward as it was rewarding. The How part of the manual, section 1, is very well laid out and easy to follow. Clearly written and full of helpful diagrams, you’d have to try to mess it up. As Perry points out, take your time and enjoy the process. Don’t rush; when you’re done, you will have made something that you’re proud of.

When I finished building my Legendarium and it was time to listen, I was very satisfied. Doing my best to set aside the “I put this beauty together and I know how it works” feeling, objectively, it’s a great listen. It does bring a characteristic tube smoothness, but it’s not fat, rich, warm, etc. It’s transparent and revealing, but so easy to listen to. I can (and do) listen for hours and hours. There is mid-range bloom and top-end sparkle, and other adjectives that don’t seem related to sound…

The most honest thing I can say is just that I love to listen to music played through this amp. For reference, I listen to a lot of jazz (all the standards you know and some really out-there stuff), I’m a big Pink Floyd, King Crimson, and Rush fan. Betty Davis, The Doors, Velvet Underground, and on, and on, and more obscure… The Legendarium plays all of this with articulate speed and texture, tonal balance and nuance, space… you get the sonic picture. There are some songs better played on other amps. My old punk albums, for example, have more energy when presented through an amp with more balls. But such is the nature of punk music! It still sounds good on the Legendarium, it just doesn’t sound as right as everything else.

Also for reference, I’m listening to music via a Hana ML cartridge mounted on a Pro-Ject RPM 5 turntable, playing into a Pro-Ject Tube Box DS 2, which drives the Legendarium. I’ve been using Klipsch Forte III’s until recently, when I switched over to DIY Tang-Band based, full-range, open baffle speakers. The Legendarium does fine with both sets of speakers. I’ve never turned the volume past 50%. I’m also not in a very big space. As has been noted in at least one other review, the Legendarium does produce an audible hum if you’re close to your efficient speakers. I can hear mine when I change a record, but not when I’m in my chair. It’s directly heated. There are pros and cons. Relax and enjoy the music. I really think you will.

Customer from California


If you want to jump right into a direct heated triode set amp and you have little experience with vacuum tube sound, Perry's Legendarium is your ticket to audio bliss. This amp has been pumping out tunes since I got it about a 3 weeks ago, displacing my well burned in Mogwai SE. A good sounding amp doesn't need you to refi your house or get a bank loan. This amp is amazing 3.5w of music bliss.

Customer from Colorado


After a fair bit of online research for hand-built, relatively low power, tube amplifiers, (preferably built in the U.S.A.) of which there are a few candidates, I ran into a website for “Analog Ethos” (A.E.) which had and has three tube amplifier designs advertised, all of which may be purchased finished & tested, or as a kit. and buyer does the assembly and soldering. The artfully done A.E. website features fine photography, customer reviews and information/philosophies from Perry Board, who is “Analog Ethos”. I liked Perry’s philosophy, liked the way his amplifiers looked, was encouraged by feedback, and was persuaded, (seduced?) into plunking done the shekels for his “Flagship” amplifier offering - the 2A3 SET, “Legendarium”.  Asking for it to come finished and tested, it arrived relatively soon, well packaged, including double boxes. I had a question about pin orientation when inserting the two 2A3 tubes (of the five total tubes which came included) and emailed Perry to clarify, but finally had the new amplifier as my stereo component’s centerpiece, plugged in and ready to start doing some work. Flipped the switch to the “up/on” position and got an almost immediate, significant 60 cycle hum from both speakers! WTH? I then followed the included instructions and rotated the R&L “humpots” (located on amplifier top-plate, but mostly hidden behind the 2A3 tubes) to minimalize this hum. With my ear close to either speaker however, I could still hear the 60-cycle hum - a little bit. According to Perry, this is unavoidable side-effect of this amplifier design. So, I was a little disappointed, though once seated in a listening position I could not honestly say I could still hear the hum. I decided to say nothing to other music listeners in our home regarding this 60hz hum “issue”, and no-one yet has mentioned hearing anything untoward. I wish the Legendarium were absolutely silent, but on the other hand, if I can’t hear it from the listening position, is it really an issue?
My present system consists of Lii Audio’s, "Flagship", full-range speakers containing one “Silver Flagship 10”, (a 10-inch, cone driver) in each 47” tall, cylindrical, rear ported speaker box. Amazingly, they are, 100db efficient! I boost the low-end by using a small, $100.00, adjustable, Rolls brand, subwoofer crossover unit, sending the 80-90hz and below frequency range, (summed, R&L) to my good old PSE, solid state, 200-watt, mono, amplifier, driving a, U.S. built, 24”, Hartley driver which I have mounted in our formerly unused fireplace. Consequently, where the Liis start to wain in the low-end, the Hartley picks up the slack, while the Liis are still doing their full range work; their signal path goes into the Rolls crossover then directly back out again to the amplifier, untouched by any crossover cards. This approach makes a lovely difference and is superior to using the Liis only.  We listen exclusively to CDs using a Wadia 270 transport and a Wadia 27 D/A converter taking advantage of the latter’s volume attenuating ability, eliminating the need for another component (pre-amp) and another set of interconnects – though thoughtfully, this amplifier does come with a volume POT.  Speaking of subwoofers; more than a few listening guests over the years have asked me - gesturing towards the fireplace subwoofer, “Is that thing on?”, whereupon I go to the little Rolls crossover and turn the volume down/off and watch them. Bobbing their head up and down, they unfailingly say, “Oh, I see”. Somewhat sadly, but not surprisingly, non-audiophile humans seem to expect a subwoofer to sound like a low-rider, thumper - not like music, however they are unfailingly pleased with the sound - just a bit surprised that a subwoofer can be so subtle, yet so important.
For nearly a year we have been driving the aforementioned speaker setup with a Decware 341.5, SET amplifier with all the upgrades, probably a $3000.00 investment if one were purchasing it new (then waiting three to six months for delivery). It's a wonderful amplifier, both aesthetically and functionally, I have no complaints and am pleased I found one used, with most of the upgrades already done (no mean feat these days). The Analog Ethos, Legendarium amplifier sells for $1500 if you assemble it yourself, and $200 more to have Perry finish and test it. Not a cheap investment, but also no “get rich quick” scheme, (especially considering A.E.’s amplifiers have no printed circuit boards – are point to point, hand soldered), a labor of love, I believe.  Are they a good, long-term financial investment, will they hold and/or grow their value 10-20 years from now?  I could not find a used Analog Ethos amplifier for sale anywhere on the internet and have seen no negative talk on blogs about any of them either, which tells me something. To me, the investment is in the joy of well designed, aesthetically pleasing components and in the simple yet basic, human pleasure of quietly experiencing the joy of good music on a good system.
Being very familiar with the Decware amplifier sound, we then gave the Legendarium a good six week listen, allowing it time to break in, and us time to experience many different albums. The music this attractive, wood Chassis, aluminum decked, 3.5 wpc, Analog ethos, Legendarium amplifier makes did NOT disappoint. It is in short gorgeous, even robust. At first, I thought it was a touch low-mid-rangy strong, but after putting some miles on It, I soon grew to appreciate its balance, sensitivity and its, well - presence. It makes me think of what people say they love about the old, 60s models, British, Leak Stereo 20, “valve” amplifiers, i.e., their “pleasing, warm fullness”, though I think this amplifier, is more detailed.
All in all, despite the 60-cycle hum “almost issue”, I honestly (and somewhat surprisingly) prefer the sound and sheer listening pleasure of the Legendarium to my Decware amplifier. With that said, using other, multi-cone type driver systems, whether this would still be the case, I would not hazard an opinion, though I might speculate that using any high efficiency speakers – horns, open baffles, or any of the Lii Audio, full-range drivers that this A.E. Legendarium amplifier might just be a sweet way to go, while also saving some money – at least when compared to a new Decware amplifier. This is no knock on the Decware, SET amplifiers, but rather kudos to Perry Board for coming up with a tube amplifier design that is both aesthetically pleasing - even fun - to look at, and which produces sound with beauty, detail, and authority.  I tend to hold onto quality things and expect we will be enjoying this sweet amplifier for years to come. I would love to audition Perry’s AE1-C amplifier as well, but alas, for another lifetime.