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Linkwitz LX521.4 - new build and impressions

Definitely laced with it, though some points are... interesting, but yes, nothing to really respond to. I can't read up on some of the stuff mentioned on OPLUG - even though I'm an owner of LX Mini +2 and 521.4s, my access was revoked seemingly in retaliation for my factual account of a sub-par experience with Frank that I posted here.

Despite the manufacturing issues with my mini's which aren't a Siegfried issue, I enjoyed them until they fell apart (rebuildable, but a pain). My Madisound kit built 521.4 are still going strong, and are still my main speakers.
 
LX521 owners,

I am considering using a Genelec G3 with a Dipole sub of LX521. Listening about 3 meters away, in a room about 7X15X3.5 (meters)/22X15X12 (feet).
Keeping costs aside, what would be your comments on this approach.
 
If you accept that you won't get much response below 30-35hz in a room that size, then it's just the usual question of integrating 2 subs. See elsewhere in this forum for that.

However, it's quite important not to overpower those bass modules. Check either the Siegfried site or the oplug forum for info on the amp needs; but I know the wrong thing is overdriving open-baffle drivers, which is easy to do. Instead of pressurizing a box, you're trying to pressurize a room, and below about 35 hz you'd wreck the voice coils on those woofer drivers by pumping watts into them in the futile attempt to have a disco party.

Running those bass units from 30hz to 80hz will provide a very natural sound, which is great, much better than boxes, IMHO. But if you're doing soundtracks or movies, you need to high-pass these bass units. Trust me on that. I can readily bottom out these woofers with Hans Zimmer soundtracks. I high-pass them and added 2 DIY, dual-opposed subs below 50hz to kick the shit out of deep bass.
 
Thanks. This is for music, not movies.
I already have the LX521 subs.

I was more concerned about the clarity, tonality, soundstage etc. Basically, its much easier to get a genelec G3/8030C where I live, compared to building the LX521 top baffle part, cost wise. So unless the LX521 is vastly superior to G3, I could settle for a Genelec or a Kali.

Obviously only folks who have heard both might be able to offer advise. Hence thought of asking here..
 
Thanks. This is for music, not movies.
I already have the LX521 subs.

I was more concerned about the clarity, tonality, soundstage etc. Basically, its much easier to get a genelec G3/8030C where I live, compared to building the LX521 top baffle part, cost wise. So unless the LX521 is vastly superior to G3, I could settle for a Genelec or a Kali.
y
Obviously only folks who have heard both might be able to offer advise. Hence thought of asking here..
I can speak to the Dutch 8C, which are in that small, accomplished family of box speakers. They have superlative smoothness, more than the top baffle of the LX521. I think the combo you describe would be excellent. I think the LX521 has peerless soundstaging, esp. with classical recordings, but by no means was I ever unhappy with the Dutch. I mean, it gets to the point where you're splitting hairs. I say go for it.
 
If you accept that you won't get much response below 30-35hz in a room that size, then it's just the usual question of integrating 2 subs. See elsewhere in this forum for that.

However, it's quite important not to overpower those bass modules. Check either the Siegfried site or the oplug forum for info on the amp needs; but I know the wrong thing is overdriving open-baffle drivers, which is easy to do. Instead of pressurizing a box, you're trying to pressurize a room, and below about 35 hz you'd wreck the voice coils on those woofer drivers by pumping watts into them in the futile attempt to have a disco party.

Running those bass units from 30hz to 80hz will provide a very natural sound, which is great, much better than boxes, IMHO. But if you're doing soundtracks or movies, you need to high-pass these bass units. Trust me on that. I can readily bottom out these woofers with Hans Zimmer soundtracks. I high-pass them and added 2 DIY, dual-opposed subs below 50hz to kick the shit out of deep bass.
I agree with this take - I have the LX521.4 and in my room the dipole bass starts to struggle below 50Hz. I have them crossed over to subs (Rythmik F15HP) there so that I do not burn out the coils. I could push a little lower, but no reason.

As for the sound of Genelec vs LX521.4 baffles - that's going to be your own guess. The radiation pattern is different and the voicing is too. You are just building a sat/sub system with dipole subs. If you like what you get, then it is probably a decent system with the advantages of dipole base.
 
Monopole bass with DSP such as Dirac Live Bass Control should be considered instead of dealing with the downsides of dipole bass. I run LX521 and Dirac has been the biggest improvement I have heard with the bass region.

In my experience, dipole bass can measure much better or worse than monopole, depending on the room, speaker location, listener location, etc.
 
Thx. I find that I am able to manage bass better with the dipoles - with suitable placements. I was more concerned about the tonality and the integration between the dipole subs and the alternative-to-521-baffle.

Context is: my lx mini drivers are damaged. The 2 sub4's are OK. I didn't want to try re-buliding the LX mini again. I could either invest in the drivers for LX 521 baffle (since I already have the sub4s) or pick an alternate such as Genelecs or the Kalis. Cost wise: a pair of Kali IN-8 is comparable to the delta cost of building a 521 baffle with drivers.

(I have the amps and such - just need to build a baffle, if I go for 521).

Also, I like the tonality of JBL305mkII much more than the tonality of LX mini.
At the moment, I am leaning towards a pair of Kali IN-8s :). I am a bit reluctant to try seas again, given that I had 4 FU10RBs and 2 L16RNSLs go bad.
Also my room is about 13 wide by 25 long by 10 feet tall - perhaps a bit too small for 521.

My only concern about these Kali/Genelec/* is image stability. LX Studio has spoiled me with the image stability. Which ever way you move, the phantom scene remains intact. Things don't suddenly shift if you move your head 5 inches :)
 
Thx. I find that I am able to manage bass better with the dipoles - with suitable placements. I was more concerned about the tonality and the integration between the dipole subs and the alternative-to-521-baffle.

Context is: my lx mini drivers are damaged. The 2 sub4's are OK. I didn't want to try re-buliding the LX mini again. I could either invest in the drivers for LX 521 baffle (since I already have the sub4s) or pick an alternate such as Genelecs or the Kalis. Cost wise: a pair of Kali IN-8 is comparable to the delta cost of building a 521 baffle with drivers.

(I have the amps and such - just need to build a baffle, if I go for 521).

Also, I like the tonality of JBL305mkII much more than the tonality of LX mini.
At the moment, I am leaning towards a pair of Kali IN-8s :). I am a bit reluctant to try seas again, given that I had 4 FU10RBs and 2 L16RNSLs go bad.
Also my room is about 13 wide by 25 long by 10 feet tall - perhaps a bit too small for 521.

My only concern about these Kali/Genelec/* is image stability. LX Studio has spoiled me with the image stability. Which ever way you move, the phantom scene remains intact. Things don't suddenly shift if you move your head 5 inches :)
On the Linkwitz Lab web page, Siegfried recommended a minimum room of 240 sq. ft. with a minimum ceiling height of 8 ft. Your room size exceeds both of these handily. I run a set of LX521 baffles with the Orion bass modules in a 237.5 sq ft. room with a 7.67 ft. ceiling height and I have no issues with the smaller room size.

The sound picture the LX521 presents appears to be much cleaner and better focused than the LXminis with the Orion bass modules they replaced. I don't know if what I hear matches up with your "tonality" comments, and expectation bias could be also be playing a part on my part. However, I would not want to give up the imaging and sound quality that one obtains with the Linkwitz LX521 design for a a ported box monitor and the potential integration problems of a ported box with the LX521 bass modules.

Good luck with whatever decision you make and have fun enjoying the music.
 
I have Lx521, IN8, 8040b and kh120.

The Lx521 bass modules sound slow and ponderous with my active monitors. If you were starting with monitors they would be totally the wrong choice. The bass modules work best 50-300Hz.
Your better off building the Lx521, or selling the bass modules and buying sealed subs.
 
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.
I'm new to this forum and since I have some Lx521.4s in the living room and a 11.4.4 theater in the basement using 7 Lx minis I found this thread interesting particularly Erin's testing of the Minis and Frank's comments on the dip he showed as compared to SL's original testing. I looked around a bit trying to find out what amps, pre-amps, and testing equipment, etc he was using but couldn't find much other than he switched from the Klippel to the Dayton Omni mic setup. I did find where he was doing his testing listed on his website.

"All my testing is done in my garage. It is not an ideal environment but I have taken steps to ensure the data is as accurate as it can be. This means spot treating the room with acoustic panels, and testing when the temperatures are approximately equivalent to ensure accuracy and consistency within my own data set."
 
Cost wise: a pair of Kali IN-8 is comparable to the delta cost of building a 521 baffle with drivers.

(I have the amps and such - just need to build a baffle, if I go for 521).

I suggest alternative drivers for the 521 baffle -- they are cheaper, and to my ears, sound better: The 8" low-mid driver and 4" high-mid drivers are from John K's NaO Note II OB design; the dipole AMT tweeter is my personal fave for any multi-way OB system.

Instead of Seas U22REX/P-SL (H1659-08) 8", use ScanSpeak 22W8524
Instead of Seas MU10RB-SL (H1658-04) 4", use ScanSpeak 10W4424 (or 8424) -- this is audibly superior to the Seas even compared held in one's hands.
Instead of 2x Seas 27TFFNC/G (H1396) 1" Tweeter, use Aurum Cantus AST2560 AMT tweeter (fascia removed, back open)
 
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I'm new to this forum and since I have some Lx521.4s in the living room and a 11.4.4 theater in the basement using 7 Lx minis I found this thread interesting particularly Erin's testing of the Minis and Frank's comments on the dip he showed as compared to SL's original testing. I looked around a bit trying to find out what amps, pre-amps, and testing equipment, etc he was using but couldn't find much other than he switched from the Klippel to the Dayton Omni mic setup. I did find where he was doing his testing listed on his website.

"All my testing is done in my garage. It is not an ideal environment but I have taken steps to ensure the data is as accurate as it can be. This means spot treating the room with acoustic panels, and testing when the temperatures are approximately equivalent to ensure accuracy and consistency within my own data set."

I think that's outdated information. The LXmini measurements were Klippel NFS, and just looking at his last review and it's also Klippel NFS.
 
the dipole AMT tweeter is my personal fave for any multi-way OB system
Thanks for the recommendations.
There are many options for the woofer, but the 10F certainly is a great driver.
Did you have look at the Radian 2.2 , too? And how easy is it to remove the back of the Aurum Cantus AST2560 AMT tweeter?
It would be awesome if you had a pic.
 
There are many options for the woofer, but the 10F certainly is a great driver.
Did you have look at the Radian 2.2 , too? And how easy is it to remove the back of the Aurum Cantus AST2560 AMT tweeter?
Actually, the ScanSpeak 22W8524 is an awesome driver for this application -- ie, nothing below 100Hz (24 dB/oct LR4 crossover) and nothing above around 1kHz. The only other ones I'd consider are the Textreme Satori drivers, esp. the 9.5" WO24TX.

10F is just about unbeatable, imo. If you dig into the pro catalogs of Beyma, etc, you might find the odd one this size that has similar linearity with higher sensitivity/power handling. That might be worth it, but I haven't looked or found one.

Did not check the Radian LT2.2 Don't think it was out when I built the system. It looks like another variation of the B&G NEO3 planar magnetic. I've used those and know the AST2560 is a bit better in almost every way.

Front plate of the AST2560 is easily removed, ditto the back. Very easy. Installation gets a bit difficult. Mine are friction fit in the baffle, which is slightly over 1" thick. A shallow waveguides for front & back could give me flush mounting on both sides... haven't got around to it yet.

PS -- AS you can see from the pic below, the OB baffle is actually a bit shorter than the original, and not ezactly the same shape, but close. It would benefit fromt being a few inches taller.

PS2 -- Also, the dual woofer config isn't the M-frame of the original LX521, but Linkwitz-W. This provide near-complete force cancellation of vibrations in the woofer frames, which makes the entire bass "box" virtually free of vibrations. Which is why I abandoned the M-frame {the left speaker system in the pic) as well as the awkward "bridge" for the upper baffle of the original. No need for it with such low vibration in the bass box.

PS3 -- if you want a pic of the backside, LMK. I can't find one but can take a fresh pic to post.
821515d1583090014-aino-gradient-collaborative-speaker-project-dsc_9924.jpg
 
Actually, the ScanSpeak 22W8524 is an awesome driver for this application -- ie, nothing below 100Hz (24 dB/oct LR4 crossover) and nothing above around 1kHz. The only other ones I'd consider are the Textreme Satori drivers, esp. the 9.5" WO24TX.

10F is just about unbeatable, imo. If you dig into the pro catalogs of Beyma, etc, you might find the odd one this size that has similar linearity with higher sensitivity/power handling. That might be worth it, but I haven't looked or found one.

Did not check the Radian LT2.2 Don't think it was out when I built the system. It looks like another variation of the B&G NEO3 planar magnetic. I've used those and know the AST2560 is a bit better in almost every way.

Front plate of the AST2560 is easily removed, ditto the back. Very easy. Installation gets a bit difficult. Mine are friction fit in the baffle, which is slightly over 1" thick. A shallow waveguides for front & back could give me flush mounting on both sides... haven't got around to it yet.

PS -- AS you can see from the pic below, the OB baffle is actually a bit shorter than the original, and not ezactly the same shape, but close. It would benefit fromt being a few inches taller.

PS2 -- Also, the dual woofer config isn't the M-frame of the original LX521, but Linkwitz-W. This provide near-complete force cancellation of vibrations in the woofer frames, which makes the entire bass "box" virtually free of vibrations. Which is why I abandoned the M-frame {the left speaker system in the pic) as well as the awkward "bridge" for the upper baffle of the original. No need for it with such low vibration in the bass box.

PS3 -- if you want a pic of the backside, LMK. I can't find one but can take a fresh pic to post.
View attachment 419434
Thank you. Nice builds.
Friction fit sounds tricky, but why not. Backside pic would be great, if not too inconvenient.

If you don't want to use the 22W above 1kHz it would not be a drop-in replacement as the LX521 has a very shallow 1st crossover order at 1kHz. You would need a different filter.
And Seas W22 or SB23 among others are not too bad either.
However, if you change the design, one could as well use a bigger woofer (and a 12cm mid that would still fit the baffle).

Have you thought about using the AMT without baffle (nude”)? The radiation is closer to dipole pattern this way. https://www.audiosciencereview.com/...-4-review-and-measurements.51449/post-2100806

Have you measured your speakers? Somehow nobody seems to measure the LX521 aside from some in room measurements that do tell more about the room than anything.
 
If you don't want to use the 22W above 1kHz it would not be a drop-in replacement as the LX521 has a very shallow 1st crossover order at 1kHz. You would need a different filter.
And Seas W22 or SB23 among others are not too bad either.
However, if you change the design, one could as well use a bigger woofer (and a 12cm mid that would still fit the baffle).

Have you thought about using the AMT without baffle (nude”)? The radiation is closer to dipole pattern this way. https://www.audiosciencereview.com/...-4-review-and-measurements.51449/post-2100806
I just meant the SS 22W is a great driver. It does bump up from around 800 to 1200Hz, and breakup happens around 3kHz. IIRC, my current xover is 1kHz LR2.

I've played with & used both SB23 variants & the Seas. They don't sound that great to me, especially at the higher frequencies, say above 600Hz. I'm pretty sure they measured worse too, but don't quote me on that.

I examined both Nao Note II and LX521 crossovers and ended up rolling my own. There were enough small differences & possible different measurement conditions. The gist of this speaker is something of a blend of those 2 designs adapted to my own space.

Yes I did measure these but measuring the FR of an OB speaker is tricky, complex. I can honestly say it resembles the Harman curve closely, with flat extension to below 30 Hz, bass up to about 150GHz elevated some 3-5 dB above 1 kHz, ~6 dB smooth downslope from about 1 kHz to 12 kHz, and then the natural downslope of the tweeter from there. If I can dig up the last set of measurements, I can post it up here... but don't hold your breath.

The trouble with no-baffle speakers is fixing them in place securely AND making them look good. Even the LX521 top baffle shape by itself is a major challenge for broad acceptance. Drivers hanging on wire frames with cables running up to them... my honey will not accept that.

You'll notice my LX521 clones are in my studio, not my LR. I had to modify the shape of the Linkwitz Orions 10+ years ago for her to accept them. But she's fine with what did with with those, both slimmer & subjectively taller than the original:

IMG_20220413_102447219_HDR.jpg
IMG_20220413_102706392.jpg
 
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