[img]http://www.hometheatershack.com/gallery/file.php?n=60506&w=s[/img]Linkwitz Lab LXmini Kit Speaker Performance Review
Plans, from Linkwitz Lab, $105.00
Kit, from Madisound, with wood parts and programmed miniDSP 2x4: $508.00
by Wayne Myers
TheLXmini is a 2 way speaker designed with the DIY hobbyist in mind by Siegfried Linkwitz of Linkwitz Lab. The pair that I am reviewing was supplied by Madisound, the do-it-yourself speaker kit and parts company, with the plans supplied by Siegfried Linkwitz, and DSP supplied by miniDSP for purposes of this build and review.
The build thread with illustrations is located here, and a YouTube video of the build process is in the final editing process, to which I will place a link here as soon as it is done.
The LXmini is a very unique design, intended as a reference speaker that can be afforded by almost anyone. Coming in at around $600 per pair, plus some elbow grease, once completely built and finished.
I had heard the LXmini at various audio shows over the last year since its introduction and was very impressed by their performance. With this review pair built and running, my first impressions match those from those earlier experiences. The LXmini is a high-performing two-way monitor in a unique, compact, attention getting form factor that is hard not to have something to say about.
The LXmini consists of a bi-amplified pair of drivers (the user must supply 4 channels of amplification) from SEAS of Norway, a producer of high performance drivers. The woofer is a 6-inch driver, mounted on top of a length of 4-inch drain pipe of the type commonly available in hardware and home improvement stores, with the benefit of a plastic clay coupler to adapt the 6-inch driver to the diameter of the tube. The upward firing woofer is active up to a 700 Hz crossover point, where a 4-inch mid/tweeter takes over, actually a full-range driver also from SEAS.
A second-order active crossover in the DSP unit from miniDSP works along with the natural acoustical coupling of the two drivers in there 90-degree relative orientation to create a transition at the crossover frequency from omnidirectional at low frequencies to dipole above the crossover.
While being designed to act as a high performance reference monitor, the design is admittedly not intended for high-volume listening levels, and will benefit from a subwoofer. The low frequency driver is the limiting device for high volume levels.
The design invites DIY innovation as far as finish is concerned. I had a lot of fun coming up with a finish for mine.
The kit, received from Madison, described in detail in the associated build thread, will call for the addition of lengths of 4-inch and 3-inch drain pipe locally, along with the aforementioned clay couplers which are commonly available (mine came from Amazon), plus paint and finishing supplies and a handful of hardware items and hookup wire.
The upward firing woofer, atop its acoustically-damped resonant tube, delivers clean, accurate bass down to 50 Hz, below which low frequency performance drops off very quickly. Mid and high frequency performance are excellent.
This pair of LXmini speakers performed in my listening room for a week, including for visitor Dennis Young, tesseract on Home Theater Shack, for a group of listeners at a get-together in Alabama, reported on in a separate thread, and is now set up again back in my personal listening room.
As already mentioned, it is hard not to get commentary on the LXmini. The design is not for everyone, and not every listener who heard them was highly impressed. For me personally, there are a number of high priority sonic delivery qualities which the LXmini accomplish with ease and which I highly appreciate and enjoy.
The trip to Alabama and back was an adventure for the LXmini. Adam at Madison told me up front that some TLC would be in order to transport them. I kept that in mind with some of the build details for this pair.
I used quick disconnect connectors in line with the speaker leads internally so the driver unit could be quickly taken off the top of each of the speakers. Getting the driver units back into place, position properly, and perfectly level again, was a bit more work than I would want to go to on a regular basis. There are also some scratches of the finish that I worked so hard on. I was able to find ways to repair them that were fairly satisfying, described in the video. But overall the amount of work involved in transporting the LXmini was a chore, so I will not refer to them as a highly portable design.
Moving around in the room or to a different room in a home is quite another matter. The LXmini is quite easy to place and appears to perform well under a variety of positioning possibilities in a room. While I did not do this extensively in my room, the characteristics of the LXmini are similar to other speakers that have even performed close to walls, unusual for high performance speakers.
Imaging is almost a given with the speaker like this, after basic care is taken with placement and set up. I very much enjoyed the sound stage, too. My speakers were carefully levelled (at the base and at the driver unit relative to the base), height matched, and aimed directly at the left and right ears, respectively of the listener at the listening position (LP).
I initially set mine up with the 2X4 DSP unit supplied from miniDSP, which normally comes with the kit from Madisound, all programmed and ready to go. Knowing that I would want to do some experimenting, I quickly switched to a 4X10 HD processor from miniDSP which I had on hand. This allowed for up to 4-way crossover setup.
I ended up with four configurations you play with.
The native two-way design for the LXmini.
A crossover added at 200 Hertz with the band below that being handled by my MartinLogan hybrid electrostatics standing close enough to the LXmini to blend with them nicely.
Same as 2, with a subwoofer crossover added at 60 Hertz.
The native two-way design for the LXmini with subwoofer crossover at 60 Hertz.
Other than the native 2-way design, I spent quite a bit of time listening to option 3, that being the configuration which took the most burden off of the low frequency driver in the LXmini, allowing for the LXmini to be driven to quite substantial volume levels beyond what the design would normally allow.
The 4X10 HD also gave me, with some simple generic remote programming, a volume/mute control and the ability to easily switch between the four configurations.
High frequency performance is very flat and extended, going clear up to the 15 kHz range before dropping off sharply. At this point, I have to report that applause is in order for the design choice of the 4-inch driver that handles the mid and high frequencies for the LXmini. High frequency performance is exceptionally clean and transparent. Dennis Young and I both appreciate and love electrostatic drivers (along with ribbon tweeters), for their transparency in that frequency range, and used that as a reference for comparing the LXmini. That little-4 inch driver delivers the mids and highs with ease and cleanness that really sparkles.
As mentioned, imaging is razor sharp, very impressive. Soundstage also is worth some detailed discussion. Basically a dipole design above 700 Hertz, I really think of it as more of a semi-dipole. There is enough damping material behind the high-frequency driver that the rear wave from the LXmini above 700 Hertz is dissipated and contribute only slightly to soundstage performance. This is perfect for me in my room. My reference speakers are Martin Logan electrostatics, with rear wave dipole performance that directly engages room acoustics in sound stage creation, a matter which I have capitalized on. I was very pleased to find out the LXmini would provide me an alternative soundstage listening experience, which involves the room much less and allows one to focus on the natural soundstage in a recording with minimum room contribution.
The resulting soundstage is quite different from that of a tower speaker or hybrid electrostatic. Height information in a soundstage tends to result to a large degree from the design of a speaker, with height information resulting largely from the relative positions of drivers. I've noticed certain sounds coming from ceiling heights with my MartinLogan electrostatics, and with the LXmini they come from the plane of the speakers primarily, with very little height generated.
Some might find this somewhat disappointing, and I will admit that it is easy to miss that height information when you first notice it, however I found that the soundstage is a much more realistic and focused soundstage, more true to the mix, if you will. Depth information is enhanced. Depth acuity, a difficult quality for most speakers to handle in soundstage generation, seemed to be enhanced by the LXmini.
Overall, the resulting soundstage from the LXmini presents as a soundstage plane, with exciting width and depth and depth acuity that go far beyond what most speakers can accomplish.
Starting out with some of my standard listening tracks, as I typically do with a new speaker. Reasons Why, Nickel Creek, the vocals on this track seemed intensely focused by the nature of the soundstage with its planner nature. The sibilance on Sarah's vocals can be a real giveaway if a speaker does not have good imaging performance in the high frequency range. Sarah's voice seems to come from a pinpoint in space with the LXmini. All of the vocals and instruments were delivered with such focused imaging by the point source design that the mix took on a strikingly focused nature that one would miss with a tower design and a vertically spread out soundstage. Each has its benefits and its own kind of fun, and I love a soundstage with height as much as the next guy if not more, but the more focused soundstage from a point source design like the LXmini has got to be heard to be appreciated.
B52s, Ain't It A Shame, echoes which normally come from the ceiling with a tower speaker all come from within the plane of the soundstage on this track. Again, the focused nature of the soundstage is really striking, and adds a focused intensity to the delivery from the LXmini. The sheen on Cindy's voice is another mix quality that is hard for some speakers to image accurately. No problem at all for the LXmini.
High frequency performance is, as mentioned, extremely flat and extended.
This will have some listeners running for a house curve to tame it, crying
too bright, too bright. For me, the cleanness and flatness of that extended high frequency range is an exciting factor in a good speaker, and the LXmini delivers high frequencies with a sparkle and transparency that I just cannot get enough of.
B52s, Good Stuff, this track is a lot of fun with the LXmini in native two-way point source mode, with their top-to-bottom point source soundstage delivery. The very busy walking bass through this track seems to be as focused as everything else in the soundstage. The LXmini, while not delivering super deep bass, nonetheless do an admirable job even at reasonable listening levels with a track like this. Overall performance even without a subwoofer is reference quality in almost every imaginable way. The LXmini have no "rough edges" and easily engage the listener with its natural delivery.
Another favorite track, My Holiday, Mindy Smith, Mindy's vocals, along with the cello and fiddle that duet in the middle of his track, demonstrate the accuracy and realism of the soundstage in native two-way mode. Rich harmonics on the stringed instruments are luscious. The enhanced soundstage depth acuity delivered by the LXmini in this mode have you placing Cindy's voice and those instruments right in the room with you. Soundstage width is downright wall erasing. The LXmini are very widely spaced in my room, wider than one would generally dare to space most speakers, the tendency often for one to end up with hole in the middle of the soundstage and some imaging tending to come apart at the seams. Not so with the LXmini. They handle a wide soundstage with ease. Mine are slightly higher than the listening plane, but that presents no problem for the high frequency drivers. They are aimed almost directly at the left and right ears, respectively. Both soundstage and imaging performance and high frequency response are optimized with this orientation with the LXmini.
The simplicity and focused immediacy in native 2-way mode were so striking that I almost hated to switch away from it for the benefit of the 4-way configuration's higher volume. Nude and Weird Fishes, Radiohead, I should point out that the LXmini can handle quite comfortable medium to medium-high listening volume in their native mode. It is for the times when one really wants to crank it up that the optional 4-way mode that I set up really became necessary.
In order to get top soundstage performance and imaging from the LXmini, minimal toe-in, which results in an off-axis listening angle and a sacrifice in high frequency response, is usually necessary. The point source design of the LXmini allows for top soundstage and imaging with a straight on-axis listening angle, so there is no sacrifice in high frequency response with a good setup. This is about the first time I have experience that, except with horn-loaded tweeters, and it was fun. Qui Dorm, Nomes Somia, Deerhoof, the experience of this track puts all those factors together into perspective. The focus soundstage and extended high frequency response together give the listener a very intense inter detail on a track like this with lots of little percussive sounds in the mix. Each stood out with a reach-out-and-grab kind of intensity. I have to say that, other than with a horn loaded tweeter design, the LXmini probably delivers more dynamic intensity and inner detail then any other speaker I have listened to in my room.
Deerhoof, Must Fight Current, I found the LXmini to be so engaging that I actually ended up backing off the volume somewhat. The natural soundstage of the LXmini will tend to be a bit more forward in the room then with a true dipole like a MartinLogan electrostatic like I am used to. That also contributed to my tendency to back off on the volume and let the soundstage settled back a little from the LP. But the inner detail also had a tendency to make me want to bring up the volume, so there was a natural balance point that I enjoyed for most tracks.
Devin Townsend, Disruptor. I was actually quite surprised at how well the LXmini could handle this track. It is densely mixed, and with other speakers has only become completely decipherable with the use of Dirac Live to improve and polish the imaging. I never tried DL with LXmini, not yet anyway. They were able to completely decipher that mix as well as I have heard it with any other speaker without the help of Dirac Live. This ended up being a real testament to the ability of the LXmini to image with precision. Radiohead, Packed Like Sardines in a Crushd Tin Box, this is another track that was a treat. The very focused, super engaging soundstage of the LXmini made listening to this track in its native two-way mode quite an experience. The soundstage extends several feet beyond the bounds of the speakers in either direction, with very direct and accurate delivery of every sound from a precise point within the soundstage. The LXmini will have many listeners going through old tracks to finding new detail that they have never caught before. Again I'm going to emphasize that the volume level possible with the LXmini alone is more than sufficient for most listening purposes and for many listeners will be more than they will ever need. This track also had me for forgetting about the need for a subwoofer and lack of depth, there was so much else going on in such an enjoyable way that I never even thought about it.
Broken Bells, Perfect World, at higher volumes of the kick drum had the low-frequency driver breaking up just a little in native 2-way mode, so I switched to my alternate 4-way mode, with my Martin Logan hybrid-electricstatics handling from 200 Hz down to 60 Hz, and a subwoofer taking over below that. The soundstage becomes slightly less focused in this mode, but is still very engaging and enjoyable. The mid and high frequency driver continues to do its job of grabbing your ears by the throat, so to speak, and delivering detail and high frequency clarity that you just cannot stop being surprised about and falling in love with. Only a few speakers I have heard give a high end that is as much fun as the LXmini to listen to, until you get into expensive ribbon tweeters in speakers 10 times and more the price.
Siegfried Linkwitz has gained a reputation over the years of engineering top notch designs and turning them into kits for Do-It-Yourself speaker builders to enjoy. Those who shy away from DIY projects because of the work and trouble or because of their lack of skill in such matters, or who believe that the result will be in some way inferior to a manufactured product, are just plain missing out. The LXmini is a fun and relatively easy build, and in terms of performance will knock the socks off of most extremely picky listeners. Admittedly the point source type soundstage may be off-putting to some. As I said, I like a high soundstage, too, and have that with my main Martin Logan electrostatics. For a listener who has a room with particular challenges for speaker placement or needs a very small speaker, the LXmini is extremely small and easy to place in terms of real estate and ability to sounds great in a variety of set up positions. Delivering awesome levels of bang-for-buck performance, I give the LXmini my highest recommendation for a speaker in the price range, reminding the listener that subwoofers will probably be needed for those who want significant bass performance or want to run at higher levels of volume. For the listener who is willing to put together a kit and is looking for reference level performance with very focused, detailed imaging and soundstage that helps you forget where you are and pulls you right into the mix, the LXmini is a speaker that will surprise and please you for sure.
Go to the Linkwitz Lab LXmini Kit Speaker Performance Review Discussion Thread.