Why SET can be an excellent match. "In my early to mid twenties, I hung out with two gents from Belgrade who both passed away since, Vujadin Erkic and Nikola Vukusic. They were exclusively into single-ended triodes. They ran 211 whose 1'200 volts came from battery stacks, 845, 811, GM70 and such, graphite anodes being their preferred choice and +1'000V their normal PSU voltage. Because they weren't part of the military surplus of the former Yugoslavia, 300B they didn't much care for. I somewhat grew up around their SET sound even though I didn't always share their opinions on what a circuit's better iteration was.

"But aside from working on ribbons, I got into building single-ended Mosfet amps for my own pleasure inspired by Nelson Pass. To me a proper SET is about dynamics, immediacy, a lightning-fast midrange and attack. If an amp's topology allows and your transducer can work with a low damping factor, the absence of negative feedback can add another layer of vividness, immediacy and texture. I've only come across that with triodes and static-induction transistors preferably in single-ended mode for the correct distribution of low-order THD. In my opinion, the vividness of well-executed SET amps is due to them not using feedback."

As before, the quotes are from Alex's forum thread to not ask him the same questions by separate emails. His Pass credit points at the FirstWatt catalogue and related circuits published by Nelson Pass for DIY. Luca Chiomenti of Riviera Audio Labs in Italy works to a similar THD philosophy influenced also by Jean Hiraga. For classic Western Electric-inspired SET amps there's Shigeki Yamamoto of Yamamoto Sound Craft in Japan with amps like this 300B with volume control, C3m pentode drivers and tube rectifier. In South Korea Kang Su Park's Allnic Audio plies a similar trade whilst with the demise of Don Garber's Fi, Gordon Rankin of Wavelength Audio stands tall as a current US brand that works this sector. From China come Cayin and Melody with classic SET proposals. It's simply key to acknowledge that SET can also stand for single-ended transistor amp, even single-ended tetrode like Tektron's KT170 models; and that no-feedback transistor circuits exist like Ayre's. Again, users pursuing or already owning a 300B-type speaker amp like this Yammy will likely order the impedance interface at 8Ω or 16Ω to transfer more power.

From head-fi.org poster Simorag who travelled to Serbia to acquire his Immanis pair directly from Alex. Note his choice of Riviera Audio Labs amplifier; and the Spirit Torino Valkyria for dynamic cans.

About pad options, "we offer just one and exactly the same type for Magna and Immanis. Of the four that suited my acoustic specs, I tried and tried what Dekoni sent me and one clearly stood out above the others." So Alex doesn't play the 'season to taste' game of interchangeable ear pads with different tunings. He offers the one which performs best; and from the same premium supplier which furnished me with superior replacements when my Susvara stock pads busted their seams.

About sales: "For countries with established Raal 1995 representation, we'll have dealers. For other countries without dealers, we will sell direct. There is no intention to create a regular web shop here in Serbia because our laws prevent us from tying a company account to PayPal or some other credit-card interface. I'm limited to Swift transfers for which email is sufficient. Also, taking a personal call or email to chat to interested parties is so much better than an impersonal web transaction and allows me to clear up questions on usage, appropriate ancillaries and technical matters. We already have distributors for the three German-speaking countries, Italy, the US, Singapore and China. More are coming."

About the stand/interface: "We're still awaiting the leather wrap for its mushroom top and black anodizing its stem which screws into the black transformer column with wood-veneer top. Our tailor is working up the first leather treatment right now to see whether it'll turn out as envisaged to have better grip on the headphones and prevent slippage. If we're unhappy with how the leather appliqué looks, we'll revert to bead blasting and black anodizing to match the bottom section of the interface."

More about on how the interface may shift the following amp's signature: "How an amp's behaviour changes depends on the load. With the HSA driving ribbons direct or via the interface as a sometimes do at shows is a very specific demonstration of how an amp responds to an extremely different load. In ribbon-direct drive, the HSA-1a/b/c loads at 1Ω which is the sum of the ribbons, cable and internal ballast resistor. Now higher-order harmonic distortion becomes more pronounced than loading the amp at 32Ω with the interface which mellows down higher-order THD significantly. That's no surprise when the current the amp must swing now is ten times less. It's not really that the transformer interface 'rounds off' the sound. The amp behaves different into a harder (lower-Ω) load.

"A single-ended power JFet amp like the FirstWatt J2 acts very different when it loads at 8Ω or 32Ω. The distortion profile itself doesn't change as it has nothing beyond the 5th harmonic in the first place. It's the quantity of distortion which shifts. At 32Ω it sounds like a regular quite neutral transistor amp. At 8Ω it sounds like a full-bodied SET because now the 2nd harmonic is up by ~15dB. Large speaker amps with paralleled output transistors at 0.5A of bias per bank pretty much never leave class A into 32Ω when asked to deliver just 2-3wpc. They either don't change at all or simply become more refined. Amps with very tight distortion control like the Benchmark AHB2 with its error-forward correction instead of classic negative feedback; or 'compound' amps whose output section nests inside the feedback loop of the input opamp don't really care. We can plug in a 2Ω load resistor in series with the headphones or a 4-32Ω transformer interface, it will sound the same just clip sooner into 2Ω.

"Basically, transformer Interfaces are very transparent and easily transfer the behaviour of the amp. However, there are large differences in how the amp itself behaves when loaded outside its expected range. In general, large speaker amps will sound pretty much the same or smoother at 32Ω, headphone amps should be loaded at 32Ω, SET at 8Ω. That way you insure that the amp maintains its familiar character and the interface simply reflects that on to the ribbons."

Public premiere on March 2nd at the Heidelberg World of Headphones event, Tankturm 4th floor. Feliks Audio Envy with TJ 300B and SAEQ for transistors. Red 3.5mm-to-2xRCA adaptors for source kit.

On cable pricing: "The 1.5m XLR4 ⇒ XLR4 and equivalent dual banana or dual spade ⇒ XLR4 is €260. That connects either a headphone or a speaker amp to the interface. The standard 1.8m headphone cable for Magna is the Satis Copper for €200. The standard 1.8m headphone cable for Immanis is the Star-8 MkII Silver for €1'000. Of course the latter is also available as an optional upgrade for Magna." On applying EQ, "these ribbons take EQ superbly so that's one way to customize their response. The German RME DAC has tone controls which are a joy to use. They're like good old Baxandall tone controls that were so natural sounding because of their slow shelving. Superb."

Alex on his first-ever Raal 1995 exhibit: "It was a great pleasure to meet so many people and their better halves. The sound was good. Some visitors preferred solid-state, some tubes, some Magna over Immanis all of which was gratifying. Got several comments that Immanis was best of show so fears about whether I did a good job were put to rest. I was very impressed with the sound from an iBasso DX320 Max Ti and now want one to do future shows with. Used the Feliks Envy SET in high-gain mode. A very fine amp [at left with Full Music 300B, at right with Elrog – Ed]. The digital players were an A&K SP3000 and SE300. I tried to keep the smoother SE300 on the HSA and the SP3000 on the Envy to reduce the contrast between tubes and transistors. All in it was a great day. I feel very lucky to have been present at the very first WOH Heidelberg in the Tankturm!"

In the wake of the Heidelberg reveal, headfonia's show report ended with a best-of-show award for Immanis by site owner Lieven. "The Raal 1995 headphones are still very new and this probably was one of the very first shows to have them available for auditioning. If you like the 'old' Raal SR-1b and ribbon sound, then the Raal1995 Immanis with its triple drivers will blow you away. It's a very high-end headphone with a corresponding price tag—around $10K—but when properly driven, is simply one of the very best headphones on the market, ever. The speed, spaciousness, positioning, resolution, transients and so on, everything is simply superb.

"If you have big pockets and just want the best of the best, look no further. The Immanis is the headphone for you, a true end-game setup." For context, the photo part of Lieven's report also shows Audeze LCD-5, Austrian Composer, Campfire Cascade, Dan Clark Voce & Expanse, Abyss Diana, Erzetich Thalia & Charibdis, Final D8000, Hedd Heddphone 2, HifiMan Ananda Nano, Meze Empyrean, Rosson Rad-o and others I didn't recognize. What's more, forum poster Fledermaus learnt in Heidelberg that Germany's Malvalve 90wpc €17K Head Amp Five with a quad of KT120 output tubes preceded by 18 small bottles has a new option. Aside from standard headphone outputs and variable energizer paths for electrostats up to 2'000VC, there's a 0.2Ω output for Raal ribbons. It's also a new option on Malvalve's Head Amp Three Mk IV, giving us two more ribbon-direct amplifier choices. Also new in the summit sphere is this audio-technica 50kg(!) fully balanced amplifier with Takatsuki 300B loaded by amorphous-core silver Lundahl transformers and 32Ω XLR4.

Immanis scoping out NYC for CanJam March 9th-10th.