New $5500 Borresen X1 Bookshelf

[Chris]

I've been waiting for these. I would very much like to hear them.

[Chris]

Good article about the design details of the new X1.

Børresen’s X1 Stand-mount Loudspeaker Feature Some Rather Unique Technology

[Chris]

Really deep dive into what makes these speakers tick. Really interesting if you are interested in innovative material science.



BTW, we are working on a special event with Borresen for later this year. Stay tuned.

[speakertom]

The technical discussion was interesting, but there was some brown stuff floating around. His claim that a larger 12 or 15" driver only uses the same area as his smaller drivers because they break up is really the exception and only happens with cheaper drivers when driven to high frequencies and amplitudes. I have never used any driver that did that. However, having a smaller driver requires more excursion to achieve similar acoustic results and you can very quickly exceed XMax on the drivers and that will quickly result in some very noticeable distortion.

He also makes a mistaken claim that is common that the bass driver must be fast to keep up with the fast mid/treble units. Again, a false assumption. Bass is slow. Take some music and low pass it at 200 Hz and you will hear how little detail is in it. What is important is to eliminate stored energy. Using a bass configuration that has cabinet resonances, ports, passive radiators, transmission lines, etc. all result in delayed energy interfering with an upper unit that does not store energy and therefore has transients that not only start quickly but also stop quickly. David Berning was impressed when I brought over a sealed box low Q sub and mated it with the electrostats he has. He also thought you could not mate a dynamic driver with an electrostat, but was a believer after that demo.

His claim that diamond and beryllium drivers have more mass and therefore require more power than his planar is true but that only relates to efficiency. What is more important is that beryllium has a combination of physical properties that make it ideal for a tweeter. The SB Acoustics Satori Beryllium tweeters I now use have more detailed transients yet are smoother than any other tweeter I have used including Sequerra T1 ribbons, Heil AMT1 AMTs, BG RD75 planars, and Janzen electrostats.

I have never heard these speakers and they may sound very good, but some of the reasons he is referring to don't hold water.

[speakertom]

Here is some info on materials for tweeters.

Tweeter material properties.pdf (255.71 KB)

The Use Of Beryllium In Transducers VUE Au....pdf (666.35 KB)