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What's new


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with Fitz






LXmini+2 & LXstudio Supplies


Burning Amp 2016


Frank Brenner explains the PowerBox and AFI-USB
Siegfried Linkwitz explains the LXmini+2

Eike Linkwitz adds the loving touch to the show. Here she lets us sample the exquisite Belgian chocolates, which an enthusiastic ORION and LXstudio builder brought along for us. Thank you, Stan!
And thanks to Wavebourn for catching this precious moment!


Thank you, to Charlie Laub and his wife Birgit Puschner, for taking on, planning and organizing this year's Burning Amp,
now that Mark Cronander (Variac) has moved to Costa Rica. 
Congratulations on a well run event!



LXmini+2 with PowerBox 6pro NCore

Where do I start? Frank Brenner piloted the LH A380 flight from Frankfurt to San Francisco arriving on a Saturday before Burning Amp on Sunday, 11/13/16. I picked him up in the afternoon at the Sausalito Ferry Terminal, still in full uniform and pushing a large suitcase, bringing a just completed PowerBox and a USB-Reclocker. We quickly drove to my home to connect his electronics to my laptop, LXmini and LXsub2. After installation of the driver for the AFI-USB on my laptop, we had sound and checked with a test recording that there were no imaging issues. I questioned the need for a reclocker, but bypassing it showed immediately a deterioration in sibilance sounds. So the reclocker stayed in and I had learned about a significant jitter effect.

By now it was high time to have dinner. As always it was lovingly prepared by my wife Eike. And then Frank had to go to bed. It was actually at 7:30 pm, somewhat past his 6 pm scheduled time, required to stay on his biological clock cycles. I packed and juggled all the equipment into my Jetta SportWagen for an early start on Sunday morning to Fort Mason with all the stuff, a hand truck and three people. 

The sound system was set up in a large, around 1000 ft2, and highly reverberant 2nd floor room in Building C at Fort Mason. It sounded great and we had many repeat visitors. We all left the show elated, but very tired. Frank got to his hotel before 6 pm for a good night's rest and flew with his two copilots, crew and 500+ passengers back to Germany on Monday.

Yesterday, on Wednesday, I had time to listen to the system in the familiar surroundings of my living room and without the background noise of a show. Wow! I sampled lots and lots of my demo material and recordings I had not heard in a long time. Wow! I contacted immediately a good friend, a respected audio recording and mixing professional, who squeezed in half hour last night to come over and listen. He is very familiar with the LXmini. He said: Fantastic, Congratulations!

The realism of sound and space is totally engaging, is emotional and can even be scary in its attacks and dynamics. I have never heard something like this in my living room. Not even from the LX521.4. So now I cannot wait to hear what more a PowerBox Master with a PowerBox Follower might do for the LX521.4.   
PowerBox - PowerHouse - PowerAmp

Here are some lessons, which I learned: 
- The USB output from the laptop needs to be cleaned up. A properly designed reclocker can do that. But if the follow-on DSP unit (e.g. miniDSP4x10HD) has as much jitter as the USB output, then there is no benefit from the reclocker. AFI-USB
- LXsub2 has a more articulated and seemingly higher volume bass output capability when driven from the 250W NCore amp, than when driven from the AT1806 amp. PowerBox
- The sweet spot for listening is closer than for a 300 angle to each LXmini. The sound stage can be huge and remains so even from off-axis angles or from a distance. 
- When listening from that close, then the LXsub2 should not aim at the sweet spot. The dipole frequency response equalization boost, which is applied to the sub, can draw too much attention at very low frequencies to the sub location. I turned the sub 450, which reduces the direct sound by 3 dB, but does not change bass output into the living room.

Frank Brenner at www.LINKWITZ.store has done just an amazing job in designing and putting the PowerBox together. This is not just a matter of assembling a Hypex DLCP, I/O interface module, amplifier and power supply modules, but about how those items are laid out and interconnected in an electromagnetically compatible order to avoid crosstalk and interference inside and outside of the metal enclosure. Bruno Putzeys, the designer of those modules, is a dear friend and like us in pursuit of excellence. He has helped Frank with advice and suggestions on occasion. Thank you, Bruno

There you have the latest. - I must now go back to the living room and listen some more.
It's addictive and healing!

Comments about the LXmini+2 system on the OPLUG



Demo of LXmini+2 System

With the LXmini+2 loudspeakers, PowerBox 6pro and AFI-USB I now have a complete system that is not too difficult to transport, because it is relatively light and fits into my Jetta SportWagen. I might be willing to travel to locations inside the Santa Rosa, Davis, San Jose and Pacific Coast triangle, if there are groups or individuals, who are truly interested in learning what magic a stereo system is capable of, when both room acoustics and psychoacoustics have been considered in the loudspeaker design. I am looking for people whose passion is music and rendering music faithfully from a well done recording. I am looking for people, who demand more, than what the high-end audio industry offers today. I am not interested in status symbol seekers or the merely curious.

Frank Brenner and I plan to have an Open House in Corte Madera  in January, probably Saturday and Sunday, 1/21 & 1/22, if Frank Brenner can get his A380 flight schedule aligned with that date. 
Watch the "What's new?" page for a firm date.




What's new?





What you hear is not the air pressure variation in itself 
but what has drawn your attention
in the streams of superimposed air pressure variations 
at your eardrums

An acoustic event has dimensions of Time, Tone, Loudness and Space
Have they been recorded and rendered sensibly?

Last revised: 02/15/2023   -  1999-2019 LINKWITZ LAB, All Rights Reserved