Audio Consulting & Boenicke

This factory tour first appeared in December 2023 on By request of the manufacturers and permission of the author, it is hereby syndicated to reach a broader audience. All images contained in this piece are the property of HifiKnights – Ed.

Although chatting with audio designers of non-conformist hardware is essential to appreciate it fully, nothing beats seeing how it's made; in person. Such insight is as invaluable as it's irreplaceable. Upon receiving an invite to visit Boenicke Audio founder Sven, I was all in. I've been up to speed on his work long before our site's 2016 launch. Thus far I've reviewed nine Boenicke products and proudly used six: W11 SE+, W5 SE, Power Gate outlet multiplier, ComDev kit, IC3 CG interconnects and S3 speaker cables. In the past I also owned his standard W8 and W5 models. That's quite a track record. Over the years Sven and I thus became friendly. That's only natural if over a decade you regularly talk to someone about a common hobby. Here one could complain that press members really should refrain from any such friendships but that's unrealistic. This biz tends to connect like-minded people who turn a passion for music and playback into a job. That's why whenever Sven and I talk, neither of us feels that we work even when that's what we usually talk about. I've been keeping tabs on Sven's social media pages where photos of his Basel HQ had the place feel strangely familiar even though I'd never been. In late October the opportunity arose to change that. Sven invited me over for a weekend to chill, have a listen to several things and show me the workshop where all his crazy ideas are born and the magic of manifesting them happens. Although I initially had no plans for penning a report about this visit, I saw too much over two packed days to keep it to myself. Apologies for photo quality nowhere near on par with what I usually provide. This time a smartphone did all the heavy lifting.

A brutally early direct flight from Warsaw to Zurich took less than two hours. Sven picked me up from the airport. He asked what I'd like to do, even kindly suggested that going to my hotel for a nap was an option. Over my dead body of course but I still appreciated the gesture. For once my schedule was open so making it busy was squarely on Sven's shoulders. He casually mentioned that he hadn't seen his crew and manufacturing facility in a while. Bingo. That's how the picturesque town of Kaltenbach located some 50km from Zurich became our first destination. A large industrial building on the outskirts houses several enterprises with Boenicke Audio being the largest to occupy the entire top floor. I'm unsure how many square meters this operation has at its disposal but the place surely wasn't small. The main area filled with cardboard boxes, paper inserts and woollen bags—hardly a surprise given how all Boenicke products pack—branched out into several smaller rooms. The first was where carpenter Christoph Schranz prepares all wooden enclosures prior to installing components. Each Boenicke speaker comprises two mirrored enclosure halves delivered to the facility as CNC-milled roughs. Christoph bonds then finishes these cabinets to render them smooth, seamless and of high tactile quality which they really are. Modest dress code plus luxurious haptics embed in all Boenicke speakers as much as top assembly, attention to detail and superb honest finishes.

From Christoph's workshop we moved to a noticeably larger room where Paddy Hablützel reigns supreme. He's responsible for assembly, QC and logistics so his daily tasks include soldering xovers, mounting drivers, wiring everything up, burning in finished products plus packing and sending them on to distributors. Considering how many already finished speaker cabs I saw in Christoph's den, Paddy has his hands full. Business must be booming. Then again, that's what happens when you run a successful audio house that launched in the late '90s. Interestingly, Sven has no aspirations to grow larger which at first surprised me. He explained that he's perfectly happy with the status quo.. He enjoys the fact that his crew maintains a healthy work/life balance which he finds super important. If it ain't broke, don't fix it. Last time I checked, being a boss who takes good care of his crew wasn't a crime.

Paddy's pad featured the usual racks full of ready-to-go crossovers, drivers and all other parts necessary to populate empty speaker cabs. It also included many exotica like large prohibitively costly Duelund capacitors, autoformers, Quantum Bybee purifiers, resonators and LessLoss Firewalls plus C-MARC hookup wiring atop many other things better kept under wraps. One side of the area was a listening space whose main system featured an affordable inconspicuously compact class AB amp from a car-audio supplier. Sven finds it powerful enough to drive his products well whilst being a tremendous tone and colour champ. This is used to check finished speaker sets ever since Paddy, a massive car audio enthusiast, discovered it. After listening for two hours to W5 monitors on rotation with W8 floorstanders, I had to admit that this kit did a very good job indeed. The last thing that piqued my interest was a statue of the company's signature widebander of the W11 and W13 models. Finally I had my chance to see how that driver's milled basket, motor and voice coil look like. Paddy also had a test for Sven and I. He wanted us to hear two W5 types with slightly different crossover points and get our feedback. Here it's worth noting that Sven has the last vote but takes his crew's feedback into account and Paddy's contribution is actually extensive as far as speakers go. Then it was time to head back to Basel.

The next day Sven had a firm plan on how the day would unwind. I initially thought that we were headed to his Basel office. That address was in the cards indeed yet saved for later. Right then we drove some 250km to the Geneva suburbs to visit an audio designer I've always wanted to meet, Serge Schmidlin of Audio Consulting. The name of his operation says it all. The man provides consulting services for other audio houses and is known as a boutique transformer/autoformer guru. If you haven't heard of Serge and his work, that's by design. Skilled specialists like him are paid subcontractors who silently support their clients with OEM solutions but don't get any public credit. Although it explains why Serge's client list is top secret, you'd be surprised how many well-known top brands it contains. Unlike Serge's other customers, Sven is proudly open about their association. These Swiss-made bespoke components aren't cheap so if I were a manufacturer using them, I'd be most vocal about them too. Interestingly, I was about to meet Serge the designer not the gun for hire.

The Audio Consulting roster is broad enough to assemble an entire system. It includes amps, preamps, speakers, turntables, tonearms, cartridges, cables and DACs. You won't find many reviews, however. Regular enthusiasts would consider this kit too geeky, quirky and far out. It's mostly for folks who've already exhausted the mainstream brands to feel bored. In this context Herr Schmidlin represents our hobby's dark web, a secretive resource not many people know of. Even fewer enthusiasts visit. You won't find it unless you dig deep and investigate beyond our industry's shiny surface. When you do, you'll learn that Serge's radical unorthodox products are unlike anything else but for reasons related purely to performance. Unsurprisingly some audio veterans no longer interested in bling find his no-compromise approach appealing. Just a brief chat with Serge is all it takes to understand that he's cut from different cloth. His portfolio reflects that. Serge greeted us in front of a residential house where he lives and works. Prior to going to the upstairs listening room, we had to turn off our smartphones and leave them inside a special box that prevents any aerial leakage. Our host sees unwanted airborne pollution as really bad for his electronics. Then we went to a rather small room on the first floor where Serge keeps his system. Prior to moving on let me just say that even die-hard enthusiasts would find the view inside puzzling to say the least. Really. I'd be hard-pressed to name one product that fit the usual profile. Nothing here looked conventional. The speakers on duty were Serge's tweeter-augmented Rubanoïde floorstander of 97dB/1w/1m efficiency, 35-20'000Hz bandwidth and 8Ω impedance. This 45kg affair is built upon a transmission-line bass module designed by Sven and a dipole bending-wave driver based on the Linaeum transducer developed in 1983 by Paul Paddock and Ben Stutz, since then popularized by AudioNec of neighboring France. Serge's take on this concept replaces the original plastic membranes with humidity-resistant mechanically stable paper. His highly efficient unit kicks in at 250Hz on a 12dB/oct. slope while its tall half-cylinder paper membranes on minimalist suspensions need minimal power to move lots of air.

The two boxes between the speakers were large enough to be amps but their plywood frames with mesh walls contained crossovers instead. Serge built them for easy access should he want to make changes. When I think of a crossover, I see a small module with a few components and that's it. One look at my host's networks sufficed to get the memo that he takes no prisoners. Each largest cap packed kilograms of pure silver. Compromise isn't an option. Serge wants this space and system to be the very best, looks and expense be damned. His Meteor MIPA amp and Meteor Silver Rock phono on the job were twin-box tube designs. Their large square-shaped enclosures housed battery supplies inside oval wood bodies atop HifiStay isolators. Yes, a stereo power amp that runs off the grid. Prior to visiting Audio Consulting, the only time I saw something similar was in 2015 when during our local Warsaw AVS show, Kevin Scott of Living Voice had his Vox Olympian system run exclusively off multiple battery packs. Lastly, Serge's R-evolution Meteor turntable on an elaborate pneumatic suspension made the entire structure large, heavy and somewhere in the ballpark of CHF 250'000. I've seen many turntables but nothing quite like it.

I also saw prototype 300B monos. Although their towers were in skeletal unfinished form, all parts already installed looked like bespoke hand-made efforts. I didn't dare ask how much these power amps will cost when ready; probably a small fortune. To address that financial elephant, the Rubanoïde speaker we heard sells for CHF 87'000 before VAT and other import duties, the twin-box Meteor MIPA amp and Meteor Silver Rock phono for CHF 64'400/58'600 respectively. Prohibitively expensive Swiss manufacturing partially explains these figures and, as it quickly turned out, so does the system's performance. It sounded unexpectedly good and very surprising. You'd think that if a setup looks this non-standard, it must sound weird. That wasn't the case. Upon looking at Serge's electronics, speakers and accessories as a team, I nursed a rough idea about what to expect. High efficiency and large membranes seemed destined to sound quick, immediate, spatially open and direct. Ditto for silver transformers and magnetic volume control. Noise-killing measures and battery power promised cleanliness, resolution and tone which tubes should boost still further. Mix and stir, serve cold and it should go down rather well. Reality actually had it roughly in that ballpark. Serge's system was clearly groomed for speed and instant signal response for high effortlessness, liberated propulsion and very exciting snap. It also brimmed with easy detail to act like a magnifying glass on the tiniest nuance and dust mote under its scope. Despite this adrenaline-charged crisply outlined drive, it remained admirably smooth and not shy of tone, mass or colour. Our host is very much into older recordings and fancies vinyl so his vocabulary doesn't allow for anything even remotely dry or lean. Hence his system sounded very alive and hydrated, quite the accomplishment considering its main tuning emphasized spatial presence, image focus, high aeration and keen articulation. It also sported lovely bass that was controlled, quick, impactful, big, tactile, damped and free of drag. I'd associate this behaviour with a sealed box not transmission line. More importantly, when that kind of bass meets suchness and bite as described, blur is left at the door and the sensation of high momentum and impact is constant. All things considered, I'd file Serge's system away as meticulously curated so thoroughly sorted across the board and free from obvious weaknesses. It was apparent that he's invested a lot of time to tune it that way. Colour me very impressed.

After spending several hours with Serge, it was time to head back to Basel. Boenicke Audio HQ at the Ramsteinerstrasse 17 near the Rhein river was our next and final stop. Here Sven showed me the small basement where he keeps parts to assemble his electronics which he builds by hand. A separate entrance several meters away led to the 135m² area of his personal listening room. Half this space is occupied by a friend who runs a printing agency. The combined place is more than enough for them both and as I was about to find out, acoustically happy without a single diffuser or absorber in sight. The view in front of a large couch comprised a massive wooden rack for Boenicke electronics. On duty was his top-shelf v3 preamp, p3 power amp and two upcoming products, the c2 DAC and Sublime Voltage Conditioner aka SVC. Add to that a Metronome DSS 2 streamer, multiple Boenicke cables, accessories and presto, that's what I was about to hear. A vintage Sony transport heavily modified by Volker Bajorat of Clockwork Audio sat on the same rack. Sven relies on this CD player during audio shows so I expected that it'd be our weapon of choice for the evening's audition. It wasn't. He wanted us to hear music I like and know so streaming was the ticket.

The star of the show was Sven's latest W22 floorstander. Its list of unique goodies is rather long. The accoya or mahogany solid-wood enclosure can accommodate customer-selectable solid wood side panels on Sven's proprietary SwingBase flotation. An AER cone tweeter custom-made specifically for the W22 boasts 101dB@2.83V/m sensitivity, ultra-linear response, a powder-coated bell-bronze curved baffle, paper voice-coil former, aluminium-alloy voice coil wire, double C37 lacquered foam-surround carbon membrane and bell-bronze phase plug. Harmonix RF 5700 tuning dots sit on the magnet and speaker terminals. An Audax tweeter on the rear boosts ambience. A custom-made Supravox 285 mid/woofer runs without filter like a classic widebander. It features a bell-bronze phase plug, C37-lacquered cellulose diaphragm, paper former and aluminium voice coil, both of the latter coated with C37 lacquer. The AER and Supravox rely on a proprietary friction-free suspensions and see Boenicke's latest-gen double series and single parallel resonators. Speaker terminals are Furutech FT-816. The internals feature Lessloss coaxial C-MARC hookup wiring, Duelund tinned copper paper-in-oil cast capacitors and an Audio Consulting custom-made bypass cap for the tweeter. This speaker also has built-in Steinmusic Speaker Match Signature bullets, Sven's ComDev devices and his own acoustical phase linearization networks. Each W22 further houses two latest-gen Bybee Quantum filters and 16 (!) mechanical LessLoss Firewall filters. Should you wish to know the price, that's between Sven and his clients because it includes custom options, worldwide shipping and setup by Sven himself.

Although it was rather late by now and we had only about three hours before calling it a day, this was enough to explore the W22's behaviour as its maker intends. Several months earlier in Munich I'd already heard its semi-active sealed version. Fitted with dual 15" force-cancelling woofers and a 600W class D bass amp per channel, it had this artillery DSP-aligned exactly one cycle behind the Supravox. The W22 in Basel however was a passive now vented prototype that still makes 30Hz without DSP assist to go sufficiently low for all music that doesn't include synth sub bass. Obviously any speaker is only as good as its room allows it to be. Hours earlier at Serge's, we'd heard a wholly impressive setup in a fairly small space with vaulted ceiling. Sven's space was far larger and that alone made a tremendous difference. The distance between each W22 to the front wall was a good six meters, their spacing wider still and the flat ceiling noticeably higher. About three meters or so divided couch and speakers. All Boenicke speaker no matter their size turn into imaging fiends when there's lots of space around them. Unsurprisingly here the W22 prototype staged like a monster without a clue where to draw boundaries on aural landscapes. In that sense it seemed quite endless. Then again, if you put a speaker this far away from the front wall, you expect depth layered and developed to virtually drown in it. So I drowned time and again only to be rescued by pinpoint images courtesy of that wideband driver. Serge's system had been enjoyably forward, direct and with the closest images right in front to focus attention there. Here Sven's setup maintained a different balance between sheer spaciousness, impact and intimacy where the chosen music set their ratio. Serge's voicing leaned towards radiance and outlines, Sven's expanded deeper into mystery and generous tone atop gargantuan spatial soundscapes liberated by his large room. The key difference between Serge's and Sven's system narrowed down to outlines, richness and perspective. Think watercolour fill among crisply starched images for that extra contrast pop and the sensation of here versus softer crayon fill for a more picturesque colour-intense there. That's the gist.

Vented prototype or not, the W22 also did snappy vigorous powerful bass without resonance or port noise. In most rooms including my own, I always detect some port issues but at Sven's didn't hear any. Although denser than Serge's, his system was as free from spatial confusion and time blur. It's a highly punctual, precise, articulate and orderly setup voiced to communicate these virtues as assets to substance, heft and musical beauty. The Boenicke system was very exciting but its creator's method to manifest it built upon a particularly fetching atmosphere rather than immediacy. Wild drum solos over Serge's rig were quite unbeatable. Sven's rig instead had me sold on Wardruna and Heilung where spatial expanse, moodiness and ambience step out. Chalk and cheese. For what it's worth, I wouldn't change a  thing about these two very different systems. They were awesome as is. And that's a wrap. My sincere thanks to Sven and Serge for their hospitality. You've been fantastic hosts!