On direct drive vs interface. "Our recent auditions with a new Solaja 300B² showed that even with our interface after its output transformer, it had more life, detail and breath than the direct-drive VM-1a in pentode mode with only one transformer in the signal path. The price you pay with transformers relates to their ratio. If you need a 100:1 ratio, it really doesn't matter if you combine two 10:1 transformers or use a single 100:1. Actually, you can better optimize each trafo if you divide the ratio between two. The 10:1 ratio of our interface is a very relaxed design with about 1/10th the winding turns you'll find in a typical tube output transformer. Our simpler requirements really drive down the parasitic effects which are a square function of the number of turns. We use a quality core and properly anneal the toroid after winding it. The VM-1a wasn't superior because it was a 'direct-drive' design where other amps need our interface. It's because Dragan Solaja knows a thing or two about designing great valve amps. His output transformer designed by Menno van Der Ven was a toroid which required a 0.3Ω load at its secondary to present 4kΩ to the anodes. With a single toroid, you can actually sort out the parasitic inductance even at 100:1 ratios. Other core types not fully covered in windings make that far more complex. The solid-state HSA amps are designed for 1Ω loads and have a 0.68Ω ballast resistor to not rely on the 0.4Ω/1.8µH cable resistance like Jotunheim R does. My job was to make a good interface/cable system that won't compromise excellent amplifiers from other designers. Our interface really doesn't dumb things down just to create more usage scenarios for ribbon headphones. That'd be anathema to always moving forward not back. If the interface creates more application scenarios, I'm all for it. But that's entirely a secondary benefit. My primary focus is advancing the state of the ribbon headphone art." On cost of manufacture, "after counting our work hours, increased wages following inflation, growing costs for services and materials, we can't price these any lower. They take an extraordinarily long time to build. Including control and measurements, it takes one experienced worker a full day to just make 2½ ribbons; and we have two guys making them. Still, the final sound makes it all worthwhile."

On Magna/Immanis efficiency vs Susvara. "Magna's apparent loudness equals Susvara or on vocals even feels a touch louder. Immanis goes about 2dB louder again so any amplifier of sufficient gain for Susvara will work on our new models through their 32Ω interface." On advancing the SR1a/b concept: "I gathered certain insights while working on Magna and Immanis which eventually I'd like to incorporate into new open-baffle headphones. I just don't yet know how, exactly. I think I could introduce them in perhaps two years? Most probably their wings would sit at a fixed angle with some additional padding at the top and bottom for less wiggly wear and deeper bass. Future open-baffle models would also focus on just front not back leakage. First I'll have to decide whether they should rely on dedicated amplifiers; become independent of them; or be a mix of both depending on model tier. Still, for now all that's far in the future." Why the SR1a/b themselves won't change: "Our new approach stopped exchangeable ribbons. We still slide in the frames which stretch the ribbons but the smaller gaps between frame and free ribbon edges are now so tight that we can't allow for the earlier slightly arced frames which provided friction to hold them in place. The new frames are straight and sit so loose between the magnets that they'd rattle if we didn't cement them in place. Our new ribbon tuning adjustments don't allow for the frames to be under any tension. Tension would change the tuning differences we want between adjacent ribbons inside one driver. In short, these new developments wouldn't really benefit our original SR1a/b whose single ribbon already settled at its resonant frequency."

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."

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 what Dekoni sent 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."

More on how the interface may shift an amp's signature: "How an amp's behaviour changes depends on 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 with a 32Ω 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 lower-Ω harder load. A Jfet SET 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 to the ribbons." 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."