James Croft explores patents granted to Mattias and Timothy Scheek, on behalf of Mayht Holding B.V. Our readers will acknowledge the identify from the April 2022 announcement of the acquisition by Sonos of Mayht Holding BV, for “$100 million in current money readily available.” Having adopted their work by numerous patent publications, Mayht’s expertise triggered Croft’s curiosity, for its unconventional structural designs, showing to signify recent pondering. This text was initially revealed in Voice Coil, July 2022.
Title: Low Profile Loudspeaker System
Patent Publication Quantity: US11,297,415
Inventors: Mattias Jeffrey Scheek (Amsterdam, NL); Timothy Ruben Scheek (Amsterdam, NL)
Assignee: Mayht Holding B.V.
Filed: October 26, 2018
Present Worldwide Courses: H04R 1/28 (20060101); H04R 9/04 (20060101); H04R 9/06 (20060101);
H04R 7/04 (20060101)
Granted/Revealed: April 5, 2022
Variety of Claims: 16
Variety of Drawings: 9
Summary from Patent
A loudspeaker gadget contains first and second diaphragms (12, 14) organized co-axially in an opposed relation to one another to cancel mechanical vibrations. Every diaphragm has a number of voice coils, with the voice coils of the primary and second diaphragms (12, 14) organized in the identical airplane to scale back the peak of the loudspeaker gadget.
Unbiased Claims
1. A loudspeaker gadget, comprising: first and second diaphragms organized co-axially in an opposed relation to one another and having a rear quantity in-between, every diaphragm having a plurality of motors operatively coupled thereto, whereby the motors of the primary and second diaphragms are organized in the identical airplane, whereby the body contains first and second rims supplied on the first and second ends, respectively, whereby the primary diaphragm is mounted to the primary rim by way of a primary encompass, and the second diaphragm is mounted to the second rim by way of a second encompass, whereby the body additional contains a plurality of struts extending between the primary and second rims, the motors being supplied on the struts.
Reviewer Feedback
As a result of multi-faceted points of each the expertise and efficiency claims concerned, we shall be presenting the patent critiques for this idea as a multi-part story that may seem within the subsequent a number of problems with Voice Coil.
Simply over 4 years in the past patent software disclosures of an attention-grabbing new transducer format began to look, invented by two younger gents (brothers Mattias and Timothy Scheek) from an organization referred to as Mayht Applied sciences (pronounced “Would possibly”) positioned within the Netherlands. I continued to observe their work by numerous further patent publications together with promotional bulletins within the audio press that began to look a little bit greater than 2-years in the past, together with in our personal sister journal, audioXpress.
The structural designs had been unconventional and appeared to signify some recent pondering. As I continued to observe the patent path, mixed with studying the promotional disclosures, the claims that the corporate was making had been fairly daring. Not solely had been the claims suggesting incremental developments in a single or two parameters, some claims had been orders of magnitude enhancements over the present cutting-edge in practically each important class. (The expertise is introduced on the Mayht web site at:
www.mayht.com/expertise.)
Among the key claims are (ranging from the merely spectacular and main as much as the unbelievable):
– “Completely” symmetrical and flat BL because of the Mayht magnetic system
– “Completely” symmetrical and flat Kms because of the Mayht spider leg suspension
– Extraordinarily low THD at excessive output — even in small enclosures
– The world’s first dual-diaphragm, absolutely balanced (vibration cancelling) transducer
– The identical output as a standard driver with roughly 2.5 instances bigger cone space (a 3.5” Mayht driver with two diaphragms in comparison with a typical single diaphragm 8” woofer)
– 5 instances lighter than a standard driver with the identical most output…and lastly, why not take a shot at breaking Hofmann’s Iron Regulation?
– “Air strain subject solved” — Enclosure volumes are achieved which are greater than 10 instances smaller than a standard system of the identical effectivity and low frequency bandwidth.
Usually, after we see this type of promotion of a brand new loudspeaker expertise, one can normally guess cash that a very keen advertising division has began writing the engineering specs and the truth is rather more right down to earth.
Whereas all their patents and visible demonstrations of the transducers in operation, the gadget does seem that it would at the very least be a helpful format for environment friendly packaging of smallish methods, however whereas nonetheless feeling some slightly deep skepticism about their efficiency claims, one thing very attention-grabbing occurred on April 11… I opened a monetary web page on the Web and the headline learn: “Sonos (SONO) acquires a Netherlands-based firm Mayht Holding, for $100 million in current money readily available.”
Now, if an organization buys a loudspeaker expertise for $100,000, you’ll anticipate them to have completed an inexpensive quantity of diligence earlier than financing the acquisition, but when a serious public firm purchases a loudspeaker transducer expertise for $100 million {dollars} with “money readily available,” then one would anticipate that the corporate has carried out a really thorough due diligence train, and would solely contemplate such a transfer if the diligence report was commensurate with the form of claims Mayht has made for its merchandise.
I’m aware of among the engineers at Sonos, and they’re extremely expert people with a wholesome skepticism, and any transducer boasting these capabilities must actually carry out to get previous the likes of those fellows, assuming they had been engaged within the diligence course of. So, I’ve to confess, whereas my doubts weren’t utterly diminished, my curiosity was abruptly magnified considerably.
Then, I went again and reread by all of the Mayht patent functions and likewise looked for some extra lately filed Mayht instances that had been out there in Chinese language publications that I ran by a translator.
There are quite a few patents which have been filed by the Scheek brothers and the early ones look like for single diaphragm variations that had been filed earlier than the present idea had been absolutely conceived. The structural ideas which are disclosed of their revealed patents seem to at present be cut up into a number of classes:
- Skinny, dual-diaphragm transducers with interleaved, cross-coupled motor buildings
- Specialised connector methods between the voice coils and the diaphragms
- A distinct configuration and placement of the centering spiders
- A compliance-enhancing foundation for overcoming air spring stiffness in small enclosures
On this first assessment phase of the multi-part sequence, we’ll discover the primary patent for the skinny, dual-diaphragm transducers with interleaved, cross-coupled motor buildings.
Among the first system twin diaphragms, interleaved motor, ideas which have been proven within the newest gadgets on their web site are disclosed in a 2017 submitting, which was granted in April of 2022 as US11,297,415. That is the patent that we are going to discover right here.
As a primary stroll by of the essential construction, referring to Determine 1A and Determine 1B, the loudspeaker transducer 10 is illustrated comprising a primary diaphragm 12 and a second diaphragm 14 organized co-axially in an opposed relation to one another. On this embodiment, as with many of the publicized gadgets, the diaphragms are of a flat, round type. Between the primary and second diaphragms is a shared “rear wave” quantity 15.
The loudspeaker transducer features a body help construction 16 having a primary rim 18 positioned at a primary finish 20 and a second rim 22 positioned at a second finish 24 of the body. The primary diaphragm 12 is mounted to the primary rim 18 by way of a primary encompass suspension (not proven) and the second diaphragm 14 could also be mounted to the second rim 22 by way of a second encompass suspension (additionally not proven).
4 vertical beams 26, equally spaced across the perimeter, lengthen between the primary and second rims 18, 22 as a part of the body 16. Cross beams 28 and 38 full the body construction 16.
Two motors 30 are mounted on the body and are coupled to the primary diaphragm 12 by their voice coil formers 36, that are spaced aside symmetrically on all sides of the diaphragm. Every motor 30 contains a magnet 32 that’s hooked up to the primary help member 28, and a voice coil 34 supplied on a former 36. The previous 36 of every motor 30 is hooked up to the primary diaphragm 12.
As with the primary diaphragm 12, the second diaphragm 14 additionally has two related motors 30’ with voice coil formers linked to diaphragm 14.
This configuration ends in the motors 30, 30’ of the primary and second diaphragms 12, 14 being organized in the identical lateral airplane, which minimizes the peak of the transducer. As in comparison with two back-to-back transducers of standard type, the place the peak profile can be twice that of a single gadget, the loudspeaker system of this invention has a claimed peak dimension that’s only one.25 instances the profile of a single-driver system. Additional, to realize this peak discount, this transducer doesn’t enhance the lateral profile in comparison with a single-driver system for the reason that diaphragms are coaxially aligned. And, working as an in-phase, bipolar transducer, mechanical vibrations from motion of the diaphragms 12, 14 in use are cancelled because of the opposed configuration of the diaphragms.
It’s claimed that utilizing a number of separate motors 30, 30’ for the diaphragms 12, 14 can enhance the effectivity, making it attainable to breed decrease frequencies in a small closed cupboard and that attaching a number of motors to every diaphragm could enhance linearity and diaphragm rigidity.
Determine 2 exhibits a transducer of comparable configuration to the one proven in Determine 1 however with a big roll encompass suspension 117 and elongated motor buildings 130, 130’ with a number of magnets 132, 132’ to optimize for bigger tour functionality, whereas nonetheless counting on the cross-coupled, interleaved motors to reduce whole transducer peak for a given tour functionality.
It’s claimed that the association of the motors 130, 130’ in the identical lateral airplane permits a most tour of every diaphragm comparable to one-third of the peak of the transducer. Referring to Determine 3, the invention is proven in a type considerably nearer to the most recent embodiments, with the primary pair of motors 330 positioned laterally exterior of the diameter of the diaphragm, with struts 360 connecting from the voice coil former 336, of voice coil 334, to the primary diaphragm 312.
By putting the cross-coupled, interleaved motor buildings exterior of the diaphragm and encompass, the system can present room for much more tour with out having the entrance and rear diaphragms and voice coil methods interfering with one another.
Whereas the disclosure exhibits illustrations of the magnetic buildings of the motor assemblies, there’s a dearth of textual content explaining what type these magnetic buildings take and the way they function. If one seems to be on the drawings, and likewise photos and movies on the Mayht web site, it seems that the motors are considerably void of any focusing components, resembling prime plates, and seem to function from the perimeter fields of the magnets themselves. Except there’s some distinctive interplay between the voice coils and the magnetic system that has not but been disclosed, it’s tough to see how this motor construction would exhibit the effectivity that’s claimed.
By way of the declare of novelty of being “The world’s first dual-diaphragm, absolutely balanced (vibration cancelling) transducer,” even limiting the search to people who even have nested, voice coils considerably in the identical airplane, to supply each vibration cancellation and a shallower bundle, a fast examine will recommend numerous prior artwork gadgets as candidates, resembling; US6,622,817 “Sound Copy System Working In keeping with the Bending Wave Precept,” invented by Wolfegang Bachmann, et al, and assigned to Harman Audio Digital Techniques GmbH; US6,931,140 “Electro-acoustic Transducer with Two Diaphragms,” invented by Aart Van Halteren and Leif Johannsen, and assigned to Sonionkirk A/S; US7,912,240 “Twin Diaphragm Electroacoustic Transducer,” by Peter Madaffari and Sietse Van Reeuwijk and assigned to Sonion Nederland; together with patent publications on extra present and acquainted gadgets, such because the KEF UniCore driver US2021/0227331 “Loudspeakers,” by Jack Oclee-Brown and Christopher Spear, assigned to GP Acoustics Worldwide; US10,631,096 “Drive Cancelling Transducer,” by Jordi Antoni Garcia Selva, et al, assigned to Apple Inc.; and US11,044,562 “Multi-Diaphragm Speaker Pushed by A number of Voice Coil Plates and a Shared Everlasting Magnet Pair,” by Leeg Hyun Cho, et al, assigned to Resonado, Inc.
If there have been a novelty of the Mayht gadget on this regard, it might appear to be extra centered on their particular strategy to putting the motors and voice coils across the periphery of the gadget and increasing connecting struts from the multiplicity of voice coil formers over to the diaphragm physique. Whereas this might appear to be an efficient expedient to additional reduce bundle measurement whereas reaching massive excursions, for lots of the “full-range” gadgets promoted by the corporate, it might appear to be tough to take care of good frequency response at excessive frequencies when utilizing this configuration.
For one of the best full-range efficiency, they could must resort to the extra standard format of getting all of the voice coils immediately coupled to the diaphragms throughout the inside diameter of the encompass suspensions.
By way of the claims that their 3.5” gadgets can equal an 8” woofer in low-frequency output, this might require their gadget to have roughly 2.5 instances the tour functionality. It’s unclear, thus far, as to how their configuration would have the power to exhibit such a big tour benefit.
Even with an Xmax of 5mm in a modest commonplace 8” woofer, the comparative Mayht gadget must obtain an Xmax of at the very least 12.5mm and for one of many higher 8” woofers, with an Xmax of 12mm or extra, it might appear that the little 3.5” Mayht gadget can be reaching tour ranges of over ±30mm or virtually 5” peak to peak. A robust declare certainly.
It is going to be attention-grabbing to see if, and the way, Mayht has developed specialised encompass suspensions and magnetics that may effectively help these sorts of efficiency numbers. Finally, the brand new construction is progressive and consists of some novel pondering and will be capable to carry out competitively with the present cutting-edge. It is going to stay to be seen if it might greatest all present loudspeaker applied sciences to the diploma they’re claiming it might.
Within the subsequent patent assessment installment, we’ll delve deeper into further Mayht patents that discover extra points of the buildings together with even stronger claims, together with essentially the most important of all: The power to scale back loudspeaker enclosure volumes to 1/tenth that of the present cutting-edge. Keep tuned. VC
This text was initially revealed in Voice Coil, July 2022
