Blueprint Acoustics’ Fresh Air OEM Subwoofer – The £50 Phone Call!
I get to be privy to some awesome insider stuff. Some time back, I was at Alpine Electronics while they were working on the Aston Martin Cygnet. This was a car ‘˜made’ by Aston Martin that you could only buy if you were invited to, by Aston. It was a Toyota Aygo with an Aston Martin Badge and leather quilted seats that had two matching leather quilted throw cushions in the back. All terribly hush-hush but the Alpine OEM department technologists were attempting to fit a system that would impress, yet had to stay under 6Kg. Otherwise, the car would have had to go through the process of homologation again, which is awfully costly and wasn’t going to happen just for the HiFi.
I have seen one, ONCE, driving around. Very cute and made to drop Aston Martin’s ‘˜average emissions’ figure divined by adding up across ALL the models the marque ‘˜made’. I don’t know if Alpine’s kit is in the Cygnet or not but I did see a bass unit lying around that day, that made my nipples suddenly erect through excitement.
It was a squashed injection-moulded plastic box with a cavity and a port and a weird shape and another port sticking out. It looked like a sort of pannini-iron cooked plastic heart with atrium and ventricle. My addled brain’s attempt to ‘˜see’ the fluid dynamics of the air movement within, struggled. It’s like being able to see The Matrix and something I always accused one Geoff Kerss of being able to do. He has been designing top end exhausts for Lotus, then Jaguar since his days in car audio. Geoff used to make unsurpassably loud bass installs that beat all comers, for as long as he competed.
So I enquire about reporting about the thing, asking ‘What in heck is it?’ Only to be told it was subject to a Non-Disclosure Agreement, which meant I could not report. Remaining within insider status relies on toeing that line, so I stored it away under ‘forgettaboutit’.
Fast forward many years, (I can still make the sound of an analogue tape squeal on moderate fast forward, on a microphone) and I am sat in the lovely XC90, on loan directly from Volvo Car UK, parked upon the paving in front of the Bowers & Wilkins’ Research Establishment in Steyning, Sussex. I am there to audition the B&W premium audio system in the press car. The video is again below but for this article, just check my face at 12m:35s for a bit and again check the little voice-over-at-the-seaside buried at the end at 16m:50s.
This article is about that woofer.
I spent fifty quid sterling on one mobile phone call to this awesome bloke. In Australia.. because the PR fellow from Harman, who supply other parts of the XC90 infotainment electronics, were happy to connect me to the source of the low frequency technology, while B&W happily acknowledged the Fresh Air subwoofer’s existence in the car. My face was four years of synthesis falling into place.
Now first off, be aware that B&W know about bass. I have been reviewing high end home and professional audio for many years (and indeed am embarking upon a plot to be doing that right here on Talk Stuff in future) and have been known for reviewing damn great big subwoofer systems. But Shaun Marin, the chap in the back of the Volvo XC90 in the video above, from B&W press dept.is an expert and did me up like a kipper with the awesome DB1 subwoofer press demo.
They had set up a small pair of speakers on stands and played some church organ music to me. It was beautiful but not a lovely deep rich bit of Bach to wake up a purring 15Hz from a 36 foot long organ pipe. It was all sweet and melodic and pastural. Lala laaaa I was gutted. I wanted to feel my innards move. Then, Shaun played the same piece of music with the subwoofer engaged. And I discovered that it wasn’t a church.
It was a cathedral.
You could suddenly FEEL the size, the space, the sheer volume of that massive stone built room for the glory of God and even get a slice of deep, visceral Cathedralic Awe! There was no boom bang crash, nor even the huge basso throbs that I so adore and are the true food of the audiophillic bass head. No, there was just SPACE. Cavernous, awe-inspiring, goosebumperacious space.
This feeling dwells alongside the subsonics, undertones and sub-harmonics that science struggles to fully describe within fluid dynamics, nor easily recreates digitally. This is why some concert halls, like the one in Gothenburg that ironically, XC90 drivers can have a slice of replication of, are so revered. The rest of the demo proved that like the huge coned B&W ASW850 subwoofer system in my living room, the DB1 is truly hench, as well as able to make all the hairs on your arms stand up, without even announcing that it was the culprit.
Wanna know a rock n roll trade secret? I can hide it here, as the folks who care in pro-audio, will never spot it deep in this epistle But Metallica’s Great Big Secret to their massive heavy metal sound that hits SO damn hard? Subwoofers. lots and lots and LOTS of subwoofers.
They ONLY played Glasto that time because their sound engineer made management triple the amount of subwoofer enclosures under the stage from twenty-one to sixty-three. Of these link
So sub bass matters, for audiophiles and head bangers alike. And without going off into a PhD treatise about bass in cars versus bass in rooms in buildings, the behaviour of bass in car cabins is very different. You get ‘˜cabin gain’ where the car’s inner acoustics boost the low frequencies in a very specific way and soak up other frequencies in odd fashions, too. And yet with the deep knowledge of the physics of the lows, B&W were happily accepting the Fresh Air woofer in the Volvo’s system. That’s a high end endorsement, believe me.
The reason is, that it melds perfectly with the rest of the system. It drops deep to neo-subsonics, to provide weight and mass to a superb OEM sound. And it provides great lumps of scale, previously unfelt in OEM car audio, with any solution yet experienced.
So what is a Fresh Air subwoofer?
You can start here, from 2m:06s to 2m:50s
And here is what Alpine say on their research pages site: ‘With an innovative Fresh Air structure, the subwoofer’s port is set up outside the car cabin and the entire cabin is treated as a giant enclosure, thus allowing a reduction of speaker size by as much as 80% for more room in the truck. It also enables a ten-fold increase in sound pressure in the ultra-low frequency range, reproducing sounds below 60Hz that regular subwoofers cannot match. Vehicle-specific optimal frequency characteristics can be set with the precise amplitude control function’
Basically, it’s a bandpass box actually mounted to be within the monocoque of the car, using the bodywork as an infinite baffle. Inside the box is a single transducer. In the XC90, it is a ten inch carbon fibre job. Both rear and front chamber are ported. The rear chamber is ported to the outside world, or into yes, fresh air! The front ports into the car and allows the lows to flow. And my word, they do. Thing is, it is way more than the not-simple-at-all bandpass enclosures that you may be used to understanding within aftermarket car audio. For one, the designer has a curve, the cabin gain, that is utterly fixed, to design that woofer response with. As against in a room, where meeting the acoustics is a bigger issue as that varies so much with each application.
Also, there is a huge degree of acoustic loading to the cone. That old thing like compressing an explosion making it more severe in effect. The driver may be breathing to the outside world (Although I gather that for long term durability’s sake, the guys at Alpine OEM do testing with the things frozen in ice, bunged up with spider nests and with ports full of mud, or with loads of dust up the port just to check that the thing will last as long as a Volvo.) but the box is very carefully shaped and the motor structure of the subwoofer driver is itself designed to work with the incredibly small enclosed volume. The white paper gets a bit dense to grasp, as well as there being perhaps a sensitive issue or two that remain not disclosed but the main issue is this bizarrely deep and even and weighty output, from a small enclosure, with a bottom octaves performance that utterly belies its cubic, power demands and driver motor size.
The technology comes from Australia, a company called Blueprint Acoustics, who license their smarts. In our territory, their Fresh Air Subwoofer technology is exclusively licensed to Alpine, who will never ever want to brag about their clientele as it simply is not the done thing. However, Greg Turnidge of Blueprint and I got on like a December bush fire (that’s summer down under) and he was wonderfully informative. Even coming out with an opinion about which car brands were better at use of their technology. I told him off and said that some things are best left out when telling writers stuff.
So, the Fresh Air subwoofer. An add-on bass transducer that hides away in the trim panels of your car and breathes its back wave out into the breeze while enlarging the quality and capability of the entire rest of your audio system. Superb quality and becoming adopted by Volvo, other corporate customers of Alpine Electronics UK’s OEM department and also, I was told, other car makers that Greg said he could not even admit to, such was their level of NDA.
But I can tell you that the best laugh in my fifty quid phone call was when I said, ‘Greg, you know, I will write that if anyone does buy into, or goes to try a car with a super-duper audio system in it from the manufacturer, that if they are wondering if it features a Fresh Air Subwoofer in it, that when they turn it up and feel their testicles move. it HAS one.’
He laughed.
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