Linkwitz LX521.4 - new build and impressions

[fourdogslong]

Yes, and as long as your amp can handle the load it works just fine. One AHB2 handles all four woofers in my setup.

Interesting, how do you deal with unity gain across all amps? Is that something the MiniDSP can handle?

 

[JP]

Interesting, how do you deal with unity gain across all amps? Is that something the MiniDSP can handle?

Typically you’d use the same amps across all channels, which is what I do. If the amp gains are different, you can adjust the level for each output on the miniDSP.

 

[fourdogslong]

Typically you’d use the same amps across all channels, which is what I do. If the amp gains are different, you can adjust the level for each output on the miniDSP.

I'm new to this so pardon my ignorance but can you tell me if I understand correctly. Let's say I use a mix of 500 watt, 250 watt and 100 watt amplifiers, as long as they all have an input gain of 15dB (random number for example) I'd be good to go?

 

[somebodyelse]

I'm new to this so pardon my ignorance but can you tell me if I understand correctly. Let's say I use a mix of 500 watt, 250 watt and 100 watt amplifiers, as long as they all have an input gain of 15dB (random number for example) I'd be good to go?

Yes, so long as they're all used within their limits.

 

[wizardofoz]

I use an 8 channel Apollon 8350 with the woofers for each side in parallel thus negating the need for 5 amps per channel. The tweeters are fine even tho the amplifier is spec’d at 350W into 8 ohms. I will at some point move the tweeters to the equal gain mp122mc hypex Module in a separate chassis.

I use Frank’s (linkwitz.store) asp v2.1 and use the MG lower mids. The ASP in the stand alone units expects to see all amps with the same input gain.

I’m very happy with this setup moving from the old lower mids and the ASP.4 from Hairball. Prior to this I was using the old original ASP from SL in the .3 setup with passive mid crossover.

Mine were the 4th pair of LX521’s built in the world and I also have an LXmini +2 setup as well as Orions and Pluto.

 

[JP]

I'm new to this so pardon my ignorance but can you tell me if I understand correctly. Let's say I use a mix of 500 watt, 250 watt and 100 watt amplifiers, as long as they all have an input gain of 15dB (random number for example) I'd be good to go?

Yes, they all need the same gain, and if not you, need to adjust the levels you feed them to compensate.

 

[fourdogslong]

I use an 8 channel Apollon 8350 with the woofers for each side in parallel thus negating the need for 5 amps per channel. The tweeters are fine even tho the amplifier is spec’d at 350W into 8 ohms. I will at some point move the tweeters to the equal gain mp122mc hypex Module in a separate chassis.

I use Frank’s (linkwitz.store) asp v2.1 and use the MG lower mids. The ASP in the stand alone units expects to see all amps with the same input gain.

I’m very happy with this setup moving from the old lower mids and the ASP.4 from Hairball. Prior to this I was using the old original ASP from SL in the .3 setup with passive mid crossover.

Mine were the 4th pair of LX521’s built in the world and I also have an LXmini +2 setup as well as Orions and Pluto.

Nice! Is the new mid woofer upgrade worth it in your opinion? Also, did you ever compare the ASP to a minidsp?

 

[fourdogslong]

That clarifies it for the amp gain, thanks everyone.

For those with the LX521.4, how good or not are they with pop/rock music? I listen to a variety of music and I work on pretty diversified stuff, a speaker that only sounds good on classical music wouldn't work for me.

For reference, I have a pair of Klipsch Cornwall IV, driven by a tube amp (I bet most people here aren't fan of that) but to my ears, that setup sounds great on most styles of music because they go low, there's precise and punchy, they reveal a bad mix easily but they also are really pleasing.

 

[mamsterla]

That clarifies it for the amp gain, thanks everyone.

For those with the LX521.4, how good or not are they with pop/rock music? I listen to a variety of music and I work on pretty diversified stuff, a speaker that only sounds good on classical music wouldn't work for me.

For reference, I have a pair of Klipsch Cornwall IV, driven by a tube amp (I bet most people here aren't fan of that) but to my ears, that setup sounds great on most styles of music because they go low, there's precise and punchy, they reveal a bad mix easily but they also are really pleasing.

Subjectively, I find them great with all types of music. I feel the way they project sound is very convincing. When I listen to electronic music, I add in 2 subs that give the visceral impact that the LX521.4 lack at the very lowest octave. I also find they are easy to correct with REW - I get a very good response in room with just a few upstream changes.

My taste in music is also quite diverse and can listen to Classical, Blake Mills, boygenius, Art Tatum in the span of a day or two. I really like how this speaker works with that variety. I also don't tend to list very loud, but have invited people over who do and they rock out and it does not get strident.

Again subjective, I think you will find that Cornwall has dynamics, but the LX521.4 is going to be far more detailed. You will constantly hear more in the music than you did before. I have heard the Cornwall only once at a show, so please take the subjectivity with a grain of salt and the bias of an LX521.4 owner.

 

[fourdogslong]

Subjectively, I find them great with all types of music. I feel the way they project sound is very convincing. When I listen to electronic music, I add in 2 subs that give the visceral impact that the LX521.4 lack at the very lowest octave. I also find they are easy to correct with REW - I get a very good response in room with just a few upstream changes.

My taste in music is also quite diverse and can listen to Classical, Blake Mills, boygenius, Art Tatum in the span of a day or two. I really like how this speaker works with that variety. I also don't tend to list very loud, but have invited people over who do and they rock out and it does not get strident.

Again subjective, I think you will find that Cornwall has dynamics, but the LX521.4 is going to be far more detailed. You will constantly hear more in the music than you did before. I have heard the Cornwall only once at a show, so please take the subjectivity with a grain of salt and the bias of an LX521.4 owner.

Thanks for sharing your experience, I will have a listen to some of the music you listed to hear a bit what you like and what you think sounds good in the LX521, this should be interesting.

I see you have the ASP v2 and a minidsp, have you compared both with the LX521?

The Cornwall is not the most detailed speaker as you say but it's still pretty clear, it's dynamics are the big selling point for me.
Listening to Supertramp Crime of the century for example on that system is simply amazing, it's so dynamic, when the band kicks in it's just awesome. Soundtracks like Mission Impossible is very involving too, you can really hear / feel the attack of the instruments, I love it.
The most detailed speaker I heard for more than a few minutes, is the ATC SCM50ASL with subwoofer, it was detailed in a way that really made me hear layers of back vocals unheard before, stereo ambiance on lead vocals that I thought were dry before, stuff like that, me and the client I was with when we heard the ATC keep talking about it every time we meet, it was a very memorable experience which I'll never forget. I wonder how the LX521 would compare.
I'd love to buy the ATC, and I probably could get a used pair for an ok price, but servicing has to be done in the UK and I'm in Canada, from what they told me, they have to do the repairs / maintenance. It's probably around 3K to have these beast shipped back and forth, it's just too much trouble/money for me unfortunately.

EDIT: listening to boygenius right now, I love it, it's a genre I quite like so it's good to know it works well on the LX521.

 

[wizardofoz]

Nice! Is the new mid woofer upgrade worth it in your opinion? Also, did you ever compare the ASP to a minidsp?

Yes absolutely if you are starting from scratch it’s the only way to go.

 

[mamsterla]

Yes absolutely if you are starting from scratch it’s the only way to go.

I agree that it does sound better. I think it is clearly lower distortion as the numbers back up. The qualitative sound is cleaner, and voices are better delineated.

 

[NHtunes]

Subjectively, I find them great with all types of music. I feel the way they project sound is very convincing. When I listen to electronic music, I add in 2 subs that give the visceral impact that the LX521.4 lack at the very lowest octave. I also find they are easy to correct with REW - I get a very good response in room with just a few upstream changes.

My taste in music is also quite diverse and can listen to Classical, Blake Mills, boygenius, Art Tatum in the span of a day or two. I really like how this speaker works with that variety. I also don't tend to list very loud, but have invited people over who do and they rock out and it does not get strident.

Again subjective, I think you will find that Cornwall has dynamics, but the LX521.4 is going to be far more detailed. You will constantly hear more in the music than you did before. I have heard the Cornwall only once at a show, so please take the subjectivity with a grain of salt and the bias of an LX521.4 owner.

The lx can do all music well. Recording quality will have a big impact on how it sounds, these speakers will showcase the deficiencies.

I am a new lx owner and I am torn about the bass. When I am in the sweet spot listening, the bass is amazing, no sub needed. But there are times I wish I had a Sub(s), but the LX bass is so sweet and I'd hate to destroy it with the subs. At this point, when I think I need a sub, I just turn it up and shake the house.

 

[CleanSound]

I didn't go looking to see if anyone has measured these LX-521.4 with a Klippel NFS or done an anechoic or quasi anechoic, but Erin measured the LXmini and boy on boy, they did not do well at all.

I want to be open minded with these speakers, especially according to Linkwitz website, Dr. Toole spoke highly of him and heck even Erin spoke highly of him in his video. Would love to be able to audition them somewhere.

 

[Jokerbre]

It should be kept in mind with which system Mr. Linkwitz measured. I'm sure he did the best he could. Proof of his theory is that the Sound Power DI is excellent on the LXmini. The concept is excellent, and it can be shaped very well.

 

[Jokerbre]

Such systems are not for people who can't see beyond a couple of lines on the graph or blindly cling to some scoring system that is barely a guide line for how something can be heard.

 

[mamsterla]

One critique I know is that Erin did not exactly follow the build directions on his LX mini - Dr. Frank Brenner who is the Linkwitz proprietor (and with whom I have spoken about it) tried to contact Erin on his observations on that video and Erin did not seem interested in taking the feedback and remeasuring. I would take some of that Kippel info with a grain of salt.

I have measured the LX521.4 in room. It did need some correction, but mainly due to my room modes and some unavoidable reflections. It is very easy to correct in room.

 

[JP]

exactly follow the build directions on his LX mini

What, specifically?

 

[mamsterla]

What, specifically?

I don't have the specifics, but let me ask Dr. Brenner. I don't want to speculate.

 

[mdsimon2]

I don't have the specifics, but let me ask Dr. Brenner. I don't want to speculate.

This is what Frank wrote on Erin's you tube review.

Hello Erin,
Thank you very much for the shown measurements and for bringing Siegfried Linkwitz´ design to people’s attention.

The whole concept is indeed very different to conventional “box” speakers and the design goals -with respect to polar radiation pattern etc. are quite different. The usual textbook formulae (Floyd Toole etc.) is something that Linkwitz did not always fully agree with. His findings are well documented on the Linkwitzlab website, many AES papers and videos can be found there.
The design result of LXmini is an unrivaled presentation of sound stage and phantom imaging, as you already experienced.

Nevertheless, let me please add some remarks:

Your measurement shows a pronounced, ca 4dB increase in frequency response on axis between 2.5kHz and 4kHz. This is certainly audible and must sound unnatural. I wonder what is going on. Siegfried Linkwitz original outdoor gated measurement (graph is shown on the website under Linkwitzlab /LXmini/Design) did not show this “bump” in frequency response. More than 100 auditions we did were free of any comments about an unnatural sound or a boost in the 2,5-4kHz region.
Siegfried Linkwitz “The resulting acoustic frequency response on the full-range driver axis is designed to be flat +/-1.5 dB from 100 Hz to 20 kHz under free-field conditions. It is 3 dB down at 45 Hz and rolls off at 15 dB/oct rate below that.”
Maybe you are not listening to the original LXmini as per design, but to a deviation of it? Where does this difference originate from? Does it come from the electronic side or from the acoustic/speaker side? You may easily check if the electronic side (a corrupt filter setup in the MiniDSP unit). The filter curves of the MiniDSP may be visualized with a (free) app like REW or ARTA and then compared to the original Linkwitz design curves, that you find on pg.23 of the LXmini construction plans and on Linkwitzlab/LXmini/ASP.
I think it is worth sorting out that issue, as it can be the start of a very joyful and satisfying experience with LXmini (or even LXmini+2/LXstudio for increased bass punch).
Upgrading to analog signal processing (Nelson Pass ASP from DIYaudio store or Linkwitz Store) would be a further step up as it avoids these ADC/DAC conversions of the MiniDSP.

The other obvious measurement is the distortion “hump” at 1,4kHz. As mentioned by Davey, it was discussed earlier in the owner’s forum, called OPLUG, in 2017. Is it audible at domestic listening levels? Some posts from year 2017 feature this:
“It is evident that the 1.4 kHz distortion appears only at elevated SPLs and goes up very quickly with the output levels. It shouldn't matter much for listening at moderate SPLs, and loud playing is not an LXmini's forte anyway. That being said, getting rid of this distortion peak wouldn't hurt...”
How to get rid of that this distortion if you find it perceivable? One owner addressed this 2nd order distortion by applying three small self-adhesive felt pads. He measured the 2nd order harmonics in that 1,4kHz range to be lowered from ca 2.5% (-32dB) down to 0.6% (-44dB), but he didn't comment on an audibility of that measure.

Compression measurements: 102dB@1m are unpleasant and damage our hearing. Linkwitz LXmini is not designed for this. At 50Hz, the woofers could have even been driven beyond their mechanical limits. For loud party applications or for PA, there are a lot of other speakers around (horns etc.)
OTOH, we demoed LXmini/+2 to a 20+ people audience at Burning Amp Festival at Ft Mason/San Francisco. The room was larger than many living rooms (ca 60 sqm / 650sqft). LXmini+2 was able to reproduce at fully satisfying volume levels and dynamics.

Erin, I hope you find the time to sort this out and that Linkwitz LXmini is not just a “measure-and-put-away” speaker for you. Indeed, it can be the start of a very satisfying journey into Siegfried Linkwitz´ designs, that allow a live-like audio experience, that is so different from many “box-type” speakers.

Best Regards, Frank Brenner / Linkwitzlab

Personally, I don't see anything there warranting a response and it reads more like manufacturer spin than anything else. I also find it telling that Frank did not provide his own recent measurements refuting Erin's but rather referred to Linkwitz's original measurements.

That being said, I actually think Erin's review is quite positive and the directivity performance is quite amazing considering the unconventional design and very DIY measurement techniques used to produce it.

Michael