Linkwitz LXmini

[Halfway Tree]

I've finally got around to building some Linkwitz LX Mini's.

I was originally going to build them from scratch, but found that getting the US size Schedule40 pipe was quite expensive in the UK due to minimum length requirements. Buying the kit from MagicLX in Germany (https://www.magiclx521.com/LXmini-speaker-kit) was almost the same price so I opted for that. It's a nice kit with everything cut very precisely. I decided to go with a modern hi-tech look and wrapped the white plastic with 3M carbon fibre vinyl, mimicking the woven upper driver. 3M carbon fibre vinyl is pressure sensitive, so fairly easy to position before fastening down. Micro holes help to ensure that any bubbles are easy to remove. MagicLX's spacers hold the upper drive in place, rather than the screws used in Siegfried Linkwitz's original plans and make for a neater build. They also groove the base so all driver wires are hidden. A single Neutrik SpeakON connector fits neatly into the base. Like all Linkwitz's speakers they are active so I use Canare 4S11 star quad cable.

So, how do they sound - like all of Linkwitz's designs they major on imaging. They're an interesting design with a polar pattern that starts off in the lower frequencies as an omni, becoming cardioid through the crossover region and dipole at the top end. Useful output down to 45Hz. They can also be used with the bass modules from my LX521s to become LX Mini Studios. This frees up the small upward firing woofer, increasing dynamics and enabling them to play much louder. They are very similar tonally to the LX521.

What Siegfried Linkwitz has done with a pair of inexpensive drivers and a couple of pieces of plastic tube is amazing. They are quite special.

https://i.imgur.com/znFvs8S.jpg

https://i.imgur.com/ipM7y9x.jpg

https://i.imgur.com/5cAFDWP.jpg

https://i.imgur.com/tN24sKX.jpg

[Bigman80]

Wow, what a funny old world. Just before I bought my speaker, I was looking at these. Tom Christiansen of Neurochrome demoed his 686 amps with a set of these. They did have meaty subs to help them out a bit though.

Great build, love the carbon look. Well done.

[Edward]

These look very interesting Gordon. Top class build.

How are you managing the crossover given that these speakers are active? Is it electronically via JRiver (as we discussed ages ago) or some other method? What amp(s) are you using to drive these?

Edward

[Halfway Tree]

Wow, what a funny old world. Just before I bought my speaker, I was looking at these. Tom Christiansen of Neurochrome demoed his 686 amps with a set of these. They did have meaty subs to help them out a bit though.

Great build, love the carbon look. Well done.

Yes, I was aware that TC has a pair...in fact he has been contributing refinements to a new active x-over configuration for the LXmini on the OPLUG (Linkwitz) forum. It puts less stress on the two drivers, although the cardiod response in the crossover region is now shorter....trade offs as usual in this hobby. Still, it enables them to go louder and still retain that magical imaging. But as you say to maximise what they can do a good sub is required. I do prefer them with the LX521 bass units, although any good sealed sub (or two) would work fine I think.

TC is a brilliant designer and you have got yourself a very fine amp there.

[Bigman80]

Yes, I was aware that TC has a pair...in fact he has been contributing refinements to a new active x-over configuration for the LXmini on the OPLUG (Linkwitz) forum. It puts less stress on the two drivers, although the cardiod response in the crossover region is now shorter....trade offs as usual in this hobby. Still, it enables them to go louder and still retain that magical imaging. But as you say to maximise what they can do a good sub is required. I do prefer them with the LX521 bass units, although any good sealed sub (or two) would work fine I think.

TC is a brilliant designer and you have got yourself a very fine amp there.Thank you, and I agree lol.

Yes, he's a very Knowledgeable bloke and the results of his work are here for anyone that would like to hear it.

Stunningly good. Pre and power

[Halfway Tree]

These look very interesting Gordon. Top class build.

How are you managing the crossover given that these speakers are active? Is it electronically via JRiver (as we discussed ages ago) or some other method? What amp(s) are you using to drive these?

Edward

Thanks, Edward.

I'm using my old MiniDSP 2x8 at the moment (same board as their current 4x10HD) as configuration files for the LXmini are available for that DSP unit. That's feeding my Nakamichi AVP1s (a couple of channels on each amp). This leaves the other channels on the Nakamichi's for my Maggie 2.5R's so no cable swapping.

I have built the required eq and x-overs in JRiver's DSP and they sound fine, but I haven't done any measurements in REW yet to verify that the transfer function is identical to the MiniDSP configuration. Unfortunately MiniDSP and JRiver do not use the same definition for Q so you can't just copy the same settings from one DSP to the other. Sounds more complex that it really is and there are a couple of online algebra calculators to do the heavy maths.

Using JRiver's DSP I send everything through my Mytek 8 channel DAC and then to my Apollon NC8350 8 channel amp (https://www.apollonaudio.com/apollon-ncmp8350-hypex-based-multichannel-class-d-amplifier/)

However, for people that might want to stay in the analogue domain Nelson Pass has developed a really nice analogue active x-over for the LXmini. (https://www.magiclx521.com/NelsonPassASPmini)

[Edward]

Phew, massive amount of useful info there Gordon. As you know I played around with electronic crossovers (using Roon), your setup is definitely a direction worth exploring further.

Would love to hear your setup some day.

§

[Gregje]

They look really cool!

[Halfway Tree]

They look really cool!

Thank you!

They sound even better than they look, but then I'm a bit biased towards Linkwitz' designs. :D

Here's what Herb Reichert from Stereophile had to say at the RMAF Show in 2014. (https://www.stereophile.com/content/rmaf-2014-reichert-sunday)

[Gregje]

I've been tempted sometimes by these. But I wouldn't want to splash out money without hearing them somewhere.
Again yours look superb!

[Halfway Tree]

I've been tempted sometimes by these. But I wouldn't want to splash out money without hearing them somewhere.
Again yours look superb!

Completely understand, Greg. I'm more than happy for you to audition the LXmini (and LX521.4) at my place, but realise it is a long trek from London.

There is an "Official LXmini Seeking Auditions" thread on the OPLUG forum (https://oplug-support.org/viewtopic.php?f=33&t=3142) where owners can offer auditions or people who would like to hear them can ask if there is anyone in their area that has LXminis.

[Qwin]

They look really neat Gordon, even better than you described to me, looking forward to hearing them soon. :)

[Floyddroid]

I've finally got around to building some Linkwitz LX Mini's.

I was originally going to build them from scratch, but found that getting the US size Schedule40 pipe was quite expensive in the UK due to minimum length requirements. Buying the kit from MagicLX in Germany (https://www.magiclx521.com/LXmini-speaker-kit) was almost the same price so I opted for that. It's a nice kit with everything cut very precisely. I decided to go with a modern hi-tech look and wrapped the white plastic with 3M carbon fibre vinyl, mimicking the woven upper driver. 3M carbon fibre vinyl is pressure sensitive, so fairly easy to position before fastening down. Micro holes help to ensure that any bubbles are easy to remove. MagicLX's spacers hold the upper drive in place, rather than the screws used in Siegfried Linkwitz's original plans and make for a neater build. They also groove the base so all driver wires are hidden. A single Neutrik SpeakON connector fits neatly into the base. Like all Linkwitz's speakers they are active so I use Canare 4S11 star quad cable.

So, how do they sound - like all of Linkwitz's designs they major on imaging. They're an interesting design with a polar pattern that starts off in the lower frequencies as an omni, becoming cardioid through the crossover region and dipole at the top end. Useful output down to 45Hz. They can also be used with the bass modules from my LX521s to become LX Mini Studios. This frees up the small upward firing woofer, increasing dynamics and enabling them to play much louder. They are very similar tonally to the LX521.

What Siegfried Linkwitz has done with a pair of inexpensive drivers and a couple of pieces of plastic tube is amazing. They are quite special.

https://i.imgur.com/znFvs8S.jpg

https://i.imgur.com/ipM7y9x.jpg

https://i.imgur.com/5cAFDWP.jpg

https://i.imgur.com/tN24sKX.jpg

Wow

[DaisyDay]

Gordon
My system may be in for a forced change soon as I've been borrowing my friends Open Baffle speakers for some time and he may want them back. Both the LX mini+2, and LX 521.4 system are options at the moment. I like the fact that numerous people have built them all over the world and the OPlug forum is full of knowledgeable people so if I get stuck I feel help would be on hand. The relative complexity i.e number of channels of amplification, wiring, dsp configuration does not appeal however and I do wonder if a simple passive Open Baffle design may get quite close on some forms of music.
The DSP/ASP, power amp options are giving me a headache especially as I'm a bit of a tight arse. I've built some scale mock ups of the LX521.4 and they look OK in the room just about, and have partial approval from the misses but I do like the less complicated build/cost benefits of the LX minis+subs option. If I choose certain DSP /poweramp combinations I can see there is a possible upgrade path allowing to move on from the Minis to the 521's but may I ask, and I appreciate this is your subjective view, if you scored the 521's as 10/10 what would you score the LxMinis and the the Lx Minis + Subs i.e what doe the 521's bring to the party, just additional volume?
Cheers
Paul