Tuesday, January 13, 2015

Open baffle speaker, anyone?

Despite my growing curiosity of open baffle speakers, they and electrostatic/ribbon speakers to date are secluded from my play list. Emerald Physics was in my mind when I was craving for a certain sound in my last upgrade urge. They are relatively affordable and widebander but I'm not confident that I could pull off dipole acoustic waveform mayhem, besides space constraint is also a limiting factor. Ahem, I don't want to mess around with something too hot to handle, furthermore I don't want to get stuck in a situation "you're neither here or there". And so, open baffle speakers and electrostatic/ribbon speakers were admired from afar. Labelled as cult, there is virtually no open baffle speaker being brought in by the local dealers, not until now.

Speaker is the hardest to get it right. While others working to minimise box colouration, some working the enclosure to reduce colourations. Among others, Dick Olsher, Siegfried Linkwitz, Danny Ritchie and many forerunners in promoting open baffle speaker. Sonic colouration is a bad thing, it is impossible to right the colouration, you wish you'd never have to confront with in the first place. It's like a wrong stroke of brush. Presumably, open baffle speaker's most thoughtful advantage, free of box colouration. In many ways, we're all got accustomed to box colouration and accepted it as a norm. The box-less idea is nevertheless inviting.

Competition is the driving force for the speaker innovation and there is a lot of study on effect of the enclosure. Besides aesthetic, the enclosure needs to sound right. To brace or not to brace, to damp or not to damp, to port or not to port, every aspect affects the sound. It is not difficult to see as you move up the echelons of speakers, the enclosure takes up a lion share of building cost. Hence, less colourations. The aesthetic of speaker reflects the owner's taste, so to speak. Wife acceptance factor also creeps in, she wants a furniture grade enclosure in her majesty the queen's living room. Question you must ask yourself, aesthetic first or fidelity first or how much you should spend on aesthetic and fidelity?

M1 Turbo
Aviation grade aluminum and bamboo sandwich are both materials the most talked about. As in the discipline of mass production, material workability and reject rate must not be taken lightly. All will raise cost. CAD is a great tool. It helps to reduce speaker development time and cost. It calculates the enclosure volume, but not enclosure shape. The study of enclosure shape has taken place decades ago, Mr Voigt pioneered the complicated Tapered Quarter Wavelength Tube TWQT, the mind boggling Hedlund speaker, various horn configurations, Audio Note insistence on wide front baffle speaker. The French champion sphere enclosure, Wilson with their so acclaimed proprietary resin but rather pedestrian box, Norh speaker employs tree trunk as gong like enclosure. B&W with their scientific Nautilus ceramic tubular enclosure, Kiso Acoustics was inspired by the making of musical instrument, Waterfall Audio with glass enclosure, YG Acoustics and Magico with high tech aluminum enclosure and the late Franco Serblin is most creative with its artisan Accordo, arch shaped enclosure. Accordo looks sexy and sets itself apart from boring enclosure, they are a wonderful piece of art. The list is far from exhaustive. That's what makes speaker the most exciting component, innovations and aesthetic in a single package.



When I chance upon Spatial M1Turbo in town, there's a urge wanting to listen to them as I never have the chance to listen to open baffle speakers.


Clone Sheva DAC
Clone 25W integrated amp
The front end is Mac feeding Clone Audio Sheva DAC in the dealer room. My short listening impression of Spatial M1 Turbo driven with Clone Audio 25i. If my memory serves me right, the room was 16 feet wide, 24 feet length and 10 feet height and with minimum treatment.


Coincidently, Spatial Audio is founded by the man who co-found Emerald Physics, Clayton Shaw. Both companies have very similar offerings and hence a natural direct competitor. M1 Turbo sports two 15 inch drivers, the top driver is a coaxial design and the bottom driver takes upon 800 Hz and below. What M1 Turbo differs from the conventional open baffle is that they do not have a wide front panel as to eliminate back waves. However, M1 Turbos do require at least 4-5 feet away from front wall to obtain the crucial 6ms time delay of reflected sound. The delayed time helps to recreate depth and sonic decay. The dealer further stressed that M1 Turbos will sound perfectly OK in an untreated small room, bye bye to ugly acoustic panel.

Albeit the dealer claimed that the newly arrived Spatial Quantum Field speaker cables are uncooked, the system sounded unlike anything I've heard before. The short one hour listening experience was an eye opener, given more time, the system will certainly open up more. M1 Turbo was placed out wide with slight toe in. In the dealer room, approximately 5-6 feet from the front wall. I am happy to report that there is no annoying honky that usually associates with coaxial drivers.

The sound I gathered from the dealer showroom is notably different from the conventional speakers. There is a degree of lightness and nimbleness to the sound. Let me tell you what they are not, they do not project ultra precision and hyper details of modern speakers. In another word, not a hi fi-ish sound. No sonic scalpel here but there is something to the sound I can't put my hand on at first encounter. Remarkably less cloudy, the absence of air turbulence throughout upper to lower registers. It sounded like the real thing. Images were lifelike in an enormous holographic soundstage and laid back. They enable a wider audible perspective. In spite of their low demeanour, they are able to project around 5 feet image height admirably. Among the registers, low registers stand out the most being remarkably accurate and natural.

I can't stop quibbling the relatively lacking in details with M1 Turbo. It seems Shaw had already acknowledged it beforehand, he fitted in a pair beryllium tweeters in his ambitious flagship Lumina 12Be Statement Dipole, smacking a walloping price tag USD20k a pair on them.

What M1 Turbos did not measure up with modern speakers, they are more than making up in free of box colouration, lively, ease and natural. My mind was constantly relating how close they sounded to live music. Live radiates omni-directional, dipoles come very close to live. The sound from M1 Turbos didn't sound as if gushing air through a pipe, this is a quality you need to hear it for yourself. I'd love to hear them again with high damping muscular amp, to impose a tighter grip on the music.

I only report the system as when and as where it is and nothing more. I have no ideas if the placement is optimal, if sufficient power to assert control, I do not know a lot of things. You will only know after you bought and brought them home. I can certainly see these open baffle speakers home to music lover people, your safety net is to contact VLS Concepts for a listening appointment to see if they are meant for you.