M2 Equipment Review by John Atkinson
 

A great read:

https://absolutehiend.com/media/wysi...tereophile.pdf

As the article states, almost no one uses sealed enclosures anymore. The speaker designer has to deal with some disadvantages in all designs. But those originating from seal enclosures usually cannot be corrected, e.g., excessive back pressure resulting in bleed-through, cabinet resonance, slow transient response, loss of sensitivity, etc.

Slow transient response?? I think you got that reversed. The other disadvantages, but efficiency (get a bigger amp), can be addressed via good execution, which is what Magico is all about.

"Facts are stubborn things; and whatever may be our wishes, our inclinations, or the dictates of our passion, they cannot alter the state of facts and evidence."

Agree! Please provide evidence.
In the mean time, please look the Magico S5 THD measurement done at the NRC. The lowest one Soundstage ever recorded. Not a single ported design came close.
According to your "facts" it should have been the other way around.

https://www.soundstagenetwork.com/in...nts&Itemid=153

Alon's comments on the sealed cabinet design pretty much address these issues, as does Magico's record in pushing the performance envelope across an expanding product line over the past decade. Remarkable achievements!!

YG Acoustics also manage to get great results with sealed enclosures.
So it can be done.

Various speaker manufacturers extol the virtues of the bass alignments they use, sealed or ported.

Their actual execution far outweighs any differences in the alignment used.

Sealed boxes have a similar roll off to transmission line, however the efficiency of such systems is lower due to the inward radiating energy not being utilised by the cabinet. Distortion also occurs as the air in the box is compressed and expanded adiabatically as the cone moves in and out, the force required to move the cone changes non linearly with respect to the cone excursion. Both sealed and vented designs usually require careful absorption to avoid rear radiating sound bouncing off the cabinet walls, and passing through the bass driver causing boxy resonances.

Transmission line by contrast sounds very natural because there is no build up of pressure behind the bass cone, with the rear radiating air being forced through an internal labyrinth to reinforce the bottom end of the frequency band. This also means no rear sound is re-radiated through the bass driver. The other advantage is that the air in the transmission line loads the bass driver and lowers its resonant frequency. This allows for the extended low end response and keeps the bass driver well damped, requiring less excursion than sealed or ported speakers to produce the same output...transmission line has enormous benefits compared to sealed and vented including improved resolution and reduced distortion, even frequency response and deeper, faster and better defined bass.

(A properly designed compression driver and horn will have even less excursion and provide a more even frequency response compared to other designs.)

I am not technically savvy enough to comment on the measured performance of ported vs sealed speakers but I do know good bass when I hear it. In my room, with my acoustical treatments, very well reviewed (and measured) ported speakers performed poorly (bass bloat). From the first second I heard bass through a Magico M3 (and before my QSub's and without changing anything else), I knew I had solved that problem. Whatever the technology does, it works for me in my room.

Cincy