Srajan
Full-size headphones. Five flavours. Dynamic. Planarmagnetic aka isodynamic. Air-motion transformer aka AMT. Electrostatic. True ribbon. Rare hybrids may combine a dynamic driver with a balanced armature like Final has done; with a self-biased piezo as EnigmAcoustics did; use twinned dynamics in an isobaric array à la Spirit Torino; or some other wrinkle. Dynamics constitute the great majority. Since the planarmagnetic renaissance started by Audeze, those have arguably become second most popular. E-stats first popularized by Stax of Japan require a ~550V bias voltage on their stator plates between which suspends the thin-film diaphragm. A specialized amp now must deliver not just music signal but energizer voltage. Today Stax are no longer alone making electrostatic headphones. Even an e-stat enthusiast has options. At present, only HEDD of Berlin make a full-range AMT headphone. For the last entrant of ribbon headphones, Raal-Requisite and new brand Raal 1995 – both helmed by Serbia’s Aleksandar Radisavljevic – are our one and only option, albeit with now four different models.
Tech talks. Planars stretch a thin non-conductive film across a rigid frame like a drum skin. Then they print or spray conductive voice coil traces onto it. Being exposed to an array of window-shutter magnets on at least one side but most often front and back for balanced drive, the excursion of a planar equates to stretching its taut membrane which has no suspension like a dynamic driver. An air-motion transformer based on the expired Oskar Heil patent takes a wide narrow non-conductive film with applied voice-coil traces then folds it into pleats which expand and contract in use. This squeezing/sucking action of air displacement claims a 4:1 to 5:1 advantage over classic pistonic drivers. A ribbon is a corrugated strip of narrow conductive aluminium. It’s fixed only on its short ends whilst magnets parallel its long sides. Unlike e-stats and planars, nothing obscures a ribbon’s radiation on either side. True also for the front of dynamics, those always put a basket and magnet on the rear. Unlike planars and their etched voice coils, a ribbon’s entire surface is conductive. That creates resistance so low as to present a virtual short to our amplifier. It’s why as speaker tweeters, ribbons pack step-up transformers to reflect 4Ω or 8Ω to the amplifier. In a headphone, the weight and size of such transformers becomes prohibitive. Now impedance conversion must go offboard. Hello, interface box.
The original SR1a/b open-baffle ribbon headphones from Raal-Requisite used multi-paralleled resistors in their interface box to generate a happy 6Ω load to our amplifier. Because those resistors converted a lot of signal voltage to heat just like a resistive volume control does, one needed a 50-100wpc speaker amplifier to pass on sufficient current to the ribbons. For the Raal 1995 models, this interface is a transformer. It’s ensconced in a cylindrical base with a removable mushroom-top stem to double as headphone stand. This transformer presents any headphone amp with a 32Ω load. As long as that amp can output ~2 watts into that impedance, happy days. Now the signal path is amplifier => interface => ribbon. The connecting cable can terminate XLR4 or 6.3mm for the amp. It enters the interface XLR4. Out it goes from there XLR4 to enter the headset 2 x 3.5mm. Because of the 0.018Ω of a single ribbon, the impedance of the preceding cable is by necessity a lot higher. That instantly acts as a low-pass filter. To cause no undesirable HF roll-off, Raal 1995 has created ultra-low impedance and minimum inductance cables, the copper Satri for the smaller headphone, the silver Star-8 MkII for the slightly bigger model. Satri can upgrade to Star-8 MkII. The transformer/cable/ribbon trinity is really an interdependent singularity broken out to suit headfi. That likely eliminates any aftermarket rolling of the actual headphone harness unless your supplier can match the extreme target parameters. The cable between amp and interface of course doesn’t fall under the same mandate. Roll away if you must, though I can’t see why you’d feel the need.
The new Raal 1995 models are called Magna and Immanis. They parallel two and three ribbons like a small line-source speaker might but wire them up in series to not drive down the combined impedance. Without a crossover, these ribbons work as classic full-range transducers. They see exactly the same unfiltered signal. By pairing or tripling ribbons of slightly dissimilar lengths, Alex deliberately avoids the same resonant frequency. From this, he promises a more linear response vaguely reminiscent perhaps of how multi-paralleled DAC chips promise lower distortion. Placing these ribbons into their magnetic channels onto a rectangular mounting plate inside a circular body naturally leaves crescent-shaped segments on all sides. It’s what has happened to any square inside a circle since da Vinci’s Vitruvian Man. In a bit of very clever trickery which I predict will soon ‘inspire’ non-ribbon competitors, Alex leaves one of those half-moon areas open. It’s the one facing forward at our schnoz. This serves a dual purpose: 1/ it depressurizes the cushion/skull cavity which otherwise would trap energized air to push on our eardrums for eventual discomfort, especially at higher SPL; 2/ it deliberately leaks some left-channel sound into the right ear and vice versa to cause a bit of acoustic crossfeed whilst broadening the in-head panorama.
Why be excited to see ribbon tech in head-fi? That’s easy to answer if you appreciate how high resolution, unfettered speed and dynamics influence good sound. The less mass a driver carries, the less energy it can store. In loudspeakers that makes the tweeter king, any big woofer the sumo pauper. In head-fi the need for drivers small enough to fit over our ears then onto our head means that regardless of tech, we deal with quasi-tweeters. It’s their proximity effect—no distance loss and only having to energize the very small cubic volume of air enclosed by pads—which allows for full-range bandwidth. But mass, unobscured airflow and excursion potential remain variables that have sonic consequences.
Any hard reflective surface like a driver basket stem or magnet becomes an instant source for reflections, air turbulence, compression and phase shift. If a planar wants to maintain good sensitivity, its opposing magnets should sit very close. Yet that proximity eats into how far the stretched film can expand before it hits an obstruction. Whilst said film is very thin and light, its actual conductive surface is far smaller than the film itself. That leaves areas which must follow along rather than being driven directly. Ditto the dynamic driver. Whilst it enjoys superior excursion from an expanding suspension, its higher mass is the sum of stiff membrane, voice-coil former, voice coil and suspension. It too isn’t driven directly. Our amp drives the voice coil which attempts to move the non-conductive diaphragm without deforming it whilst the suspension resists the intended stroke. It’s a lossy system. The e-stat’s diaphragm might be lighter even than a ribbon’s though its emissions must pass through the perforated stator plate facing our ear.
A ribbon sees zero obstruction other than whatever minimalist grill protects it; can’t store energy; and is freely suspended and expansive to here mean ±4mm of Xmax. Extremely low weight means excellent HF reproduction like an e-stat. Extreme excursion means excellent dynamics like a big cone backed by a powerful magnet. Being fully conductive unlike a dynamic or planar, a ribbon’s responsiveness is superior. Our signal voltage which the interface transformed to current drive sees every single atom of the transducer. There’s literally no dead weight which doesn’t conduct. That’s faster driver tech with superior signal tracking. So let’s ask again why we should be excited to see ribbon tech in head-fi. “But those winged ribbons look like a bizarre tinfoil helmet and the CA-1 is strange in its own way. No matter how good they might sound, I’d never wear ‘em.” Fair point. It’s exactly why the Raal 1995 models became fully domesticated head-fi ribbons. They look and wear like classic albeit luxury headgear, produce Susvara-equivalent SPL with Magna, more with Immanis, and only need headamps that can output 2 watts into 32Ω. Even my €699 FiiO R7 managed on its 3rd of 5 gain settings to leave plenty of untapped juice in the can.
To keep this Darko Remix tidy, let’s bypass all other specs. Those and far more tech talk are in my original 6moons review. Here we skip straight to sonics. As the world’s first-ever commercial ribbon headphone, the SR1a with its AKG K-1000 reminiscent wings splayed out ~20° was tuned for extreme transparency and speed like an e-stat whilst adding bass into the mid 30s passively baffle-step compensated by the interface. Without circumaural pads to make contact around the ear, their staging was astonishingly wide and free of all chamber resonances. Stoppage particularly in the bass where usual resonances throw up blur and ringing seemed abnormally quick and clean so clearly different. Rather than chase perceived weight and warmth from bloat and bloom—head-fi’s junk-food tuning of salt, sugar and fat — this bass quality was all about articulation, enunciation and precision. It removed the usual belt line of textural discontinuity above which tone textures are well damped and clean whilst below it they grow ever bloomier and smudge out into a big-bottomed pear shape. Reflexes above 200Hz were astonishing and could require acclimation, particularly in the treble which suffered no planar limitations or dynamic compression. In an untreated room, speakers not set up in the extreme nearfield add output below 1kHz, ever more so below the Schroeder frequency where room gain goes omni. Our hearing simply adjusts to how this downplays treble energies to soon call the result normal. The SR1a without any room or equivalent cup gain uncorked HF for maximal energy, presence and airiness. This and the quasi-outdoor bass qualities added up to a lighter and lither gestalt most reminiscent of electrostats with unexpected bass.
As circumaural designs with classic Dekoni pads, Magna and Immanis exploit some boundary gain. That was the only means to add bass reach and power beyond the SR1a without DSP compensation whilst avoiding out-of-phase cancellation losses. This design decision has added more body and weight to mix certain planar attributes into the core e-stat personality. Versus Magna’s smaller surface area of two ribbons, the three of Immanis can move more air to generate even better sub-bass displacement. That 1st-octave advantage creates the impression that Magna’s upper bass is a bit more prominent. Magna also stages a bit smaller though the frontal leakage zones have the side benefit of shifting the headstage forward to no longer sit like an occipital airline pillow behind our ears. The soundstage still doesn’t occur in front of us like specs but on my head sat in front of the ear-to-ear line. The ability of either model to place certain sounds well beyond the ears when a recording makes it so can be disconcerting at first. Whilst the experience isn’t the same as the no-contact SR1a particularly with its wings turned out, the actual lateral spread is unusually broad. Where the SR1a’s tuning was light and speed first, Magna by contrast feels neutral/normal, Immanis somewhat fuller. I suspect that’s down to greater moving surface and perhaps even a deliberately warmer voicing.
However, warmth as a typical function of resonance, blur and thick bass categorically doesn’t apply. A well-vented ribbon’s modus operandi is incapable of fuzziness by design. There’s nothing for sounds to hang onto, play snooker or linger. Better terms are fullness or tone weight. In speakers that tends to be the difference between a 5¼” and 7” midrange. All else being equal including tonal balance, the latter’s tone will be richer. Ditto a 12” vs 15” woofer. Where already the first hits 25Hz, the second won’t really go lower but still move more air. That’s the main divergence between Immanis and Magna. A smaller aspect is dynamic contrast, particularly across the lower three octaves. Here the triple ribbons can get shockingly physical to a greater extent than Magna. Common to both is exceptional separation of images along both axes. Whether adjacent or staggered, lesser resolution always clumps closely spaced images together. That leads to homogenized texturing. Its absence is especially obvious in the bass where our ribbons differentiate instruments or percussive beat makers to a very atypical extent.
Where classic imaging is about location specificity and placing sounds on a 3D checkerboard, timbre differentiation is about maximal textural bandwidth. Can we distinguish between a slap and a crack, a light and a strong tap, whether a drumstick had a hard or soft tip, whether a skin was a soft or taut stretch across a closed cavity or open frame made from wood or metal, whether it was a synth instead? Such mechanics shape textures. They maintain a second dimension of staging. That’s not about assigning and mapping precise locations but tracking surface textures of individual images even where clustered tightly. It’s a performance domain where the Raal 1995 models are truly spectacular and extra lucid.
Magna & Immanis combine e-stat and planar attributes then throw in dynamic range and contrast like big-coned dynamic transducers; in this sequence of seniority and dosage. Resolution, separation and speed are very high. It’s why I mention electrostats first. Bass goes very low and loud. That’s where planars come in. Such high resolution implies unusual transparency and a chameleonic response to upstream hardware changes. Swap amplifiers or DACs and enjoy magnified differentiation between their contributions. As flagship efforts which sound, look and feel the part, these are pricey objects at €7.7K and €10K with EU VAT. I rate them beyond HifiMan’s Susvara which until now was my favourite headphone. A new contributor to 6moons sold off Susvara and the big Abyss to get Immanis and – for a darker dynamic alternate – Spirit Torino’s isobaric Valkyria Titanium. Earlier he spent two domestic weeks with Sennheiser’s H1 and is well acquainted with the Warwick Aperio. We all have different tastes and hot buttons. Just so, it seems fair to say in no uncertain terms that out of the gate Raal 1995 has positioned itself right where those other greats party. So Magna and Immanis should be mentioned in the same breath as cutting-edge electrostats and the best of the planarmagnetic types beyond Audeze, Final, ZMF and Meze.
If you question why nobody else offers over-ear ribbons if they are this spectacular, you’re not alone. I wondered, too. Here’s what I know. Aleksandar will celebrate his 30th business anniversary next year. He’s done ribbons from the very beginning. Yet Magna & Immanis still took him 29 years to launch whilst his OEM ribbon tweeters found stellar accolades in premium loudspeakers around the world. That’s the learning curve. Then I’m told that to manufacture top-quality ribbons is extremely labour-intensive. It’s not something that can be automated but requires highly skilled personnel. And it’s not as though these ribbons hide. Just remove a pad and two grills et voilà. They nearly dare cloners. Alas, the SR1a launched four years ago. In the interim not a single competitor has come forward with a ribbon alternative. Now Magna & Immanis represent the next evolution in this tech’s application for head-fi. The gap is widening. Shouldn’t that make the learning curve for would-be ribbon competitors steeper still? That’s my likely answer to why, when planarmagnetics have mushroomed across all price points, the same most certainly can’t be said for ribbon headphones. It’s why the appearance of Magna & Immanis is such interesting news for ambitious listeners of the requisite scratch. Their sheer technical performance might be as close to the bleeding edge as head-fi can presently get. Meanwhile, padded leather, memory foam, aluminium and bent steel treated with scratch/discoloration-proof titanium aluminium nitride add the creature and luxury features which their pricing demands.
Now ribbon headfi has arrived!
