New build of Linkwitz LXMini

[jeffbook]

On the Orion-Pluto User Group there has been commentary over the years that some of the hi-Q peaks in the original LXmini DSP settings didn't really accomplish much. These included the peaks at 1800 Hz, 1000 Hz, and at 13100 Hz. Several users have developed alternate solutions. Some of these are discussed at length in the proprietary sections of the message boards. As a result, there are likely a myriad of EQ settings used in real life by LXmini users, many of which may not have been published.

 

[Pete Basel]

Thanks for that Jeff, I should take a look as I did buy the plans to the Pluto so I should have access.
Have there been many builders of the ASP version, or comments about the sound differences?
I was going to add that you would have thought that SL would have revised the DSP
curves based on what he found.
If I had to guess, I'd expect there to be diffraction around the mid-tweeter and perhaps
some sort of gradual transition disk might make sense around it. Perhaps 3D printed.

 

[bluefuzz]

Have there been many builders of the ASP version, or comments about the sound differences?

I have built and use the ASP. It's a couple of years since I compared it to my 2x4HD version but I don't recall any meaningful difference in sound. I think when I first set it up I may have imagined a slightly 'smoother' or 'less grainy' treble with the ASP, but that's probably placebo ... ;-)

I feed my LXminis from a NAD C658 using Dirac > ASP > DIY 4 x UCD180 amp + DIY subwoofer crossed over at 80 Hz from the NAD.

 

[Madjalapeno]

I use

MiniDSP SHD > Neurochrome Amps > LXMini

RPi + Topping D10 > Linkwitz ASP.4 > Hypex Amps > LX521

I like the ASP as I never have to worry about hitting the wrong button on the remote and screwing up all the settings. I use Speakon connectors between amps and speakers to make it as idiot proof as possible to connect.

Both sound great.

 

[Jungstar]

Congratulation on your build. Your current setup is one that I started with, using an Adcom GFA-2535 with the miniDSP 2x4. There have been several successful additions of either sealed or dipole woofer subwoofers with the LXmini. Use of one of these subs really improve the overall performance. I used my Linkwitz Orion woofers and they work very well.

Further improvement came when I replace my two Adcom 2535 amps with an 8 channel Nord amp using Ncore modules. However, your room volume would be more compatible with the LX521 than it is with the LXmini. It would be really interesting to be able to compare the performance of your D&D 8C with a full blown LX521 system.

Enjoy what you have with these two fine systems.

Quick question.... if one starts out with the LX Mini and a 4 channel amp like here... can I then add a 2 channel amp with the same hypex modules for "6 channel amp with same gain", to later add 2 x subs

 

[JP]

with same gain

That's the important part, assuming engineered amps.

 

[jeffbook]

Quick question.... if one starts out with the LX Mini and a 4 channel amp like here... can I then add a 2 channel amp with the same hypex modules for "6 channel amp with same gain", to later add 2 x subs

Identical gain is he way to go, especially if you are using Linkwitz's single woofer dipole subs to make your system a LXmini+2. This would also work if you were to use Dave Reite's sealed subs to complement you LXmini as described on the OPLUG website. With identical gain, no adjustment would need to be made to the relative gain of each channel in your DSP or ASP crossover and EQ network.

However if you want to go all the way with the LXStudio which uses the woofer modules from the LX521, you would need two NC252MP modules giving you 4 channels of amplification, 1 for each of the 4 woofer drivers.

 

[JP]

Identical gain is he way to go, especially if you are using Linkwitz's single woofer dipole subs to make your system a LXmini+2. This would also work if you were to use Dave Reite's sealed subs to complement you LXmini as described on the OPLUG website. With identical gain, no adjustment would need to be made to the relative gain of each channel in your DSP or ASP crossover and EQ network.

However if you want to go all the way with the LXStudio which uses the woofer modules from the LX521, you would need two NC252MP modules giving you 4 channels of amplification, 1 for each of the 4 woofer drivers.

NC252MP may be able to drive two in parallel, especially with LX Mini where you can't push the SPL too far anyway.

 

[Madjalapeno]

NC252MP may be able to drive two in parallel, especially with LX Mini where you can't push the SPL too far anyway.

I'm driving the subs on my LX521 system with a pair of NC400 based amps and the drivers in parallel.

 

[JP]

I'm driving the subs on my LX521 system with a pair of NC400 based amps and the drivers in parallel.

Ya NC400 no problem at all. Looks like 252 starts running out of oomph a when you get down toward two ohm.

 

[taoofdre]

Beocreate has a built-in ADAU151 DSP, so it is similar to miniDSP where the software is just a front end for programming that DSP. It has been a while since I looked at the Beocreate software but it is web based and seemed pretty flexible IIRC. My main complaint was that you used sliders to select values like frequency, Q, boost / cut, etc which was a bit of a pain.

I measured the response of various filters implemented on the Beocreate and compared to miniDSP, notably the shelf filters are definitely different between the two. Peaking filters and crossovers (I only tried second order) were the same. Like a miniDSP the Beocreate can accept biquad coefficients but the convention is a bit different with A1 and A2 swapped compared to miniDSP. Using a biquad is a good way to make sure you get the same shelf filter response as miniDSP.

If you do go with Beocreate let me know and I will fire it up again and can send you the necessary DSP settings.

Good point on the TOSLINK output @somebodyelse, definitely a really nice feature for daisy chaining an additional DSP for subs.

Michael

Sorry to dig this old post up - but is there a way to reconcile the difference between the beocreate and minidsp's shelf filters. (Is what you're suggesting with the biquad coefficients?). New to all this! Am wondering how to translate a project with published miniDSP settings to work on the beocreate (like the Directiva active crossover).

 

[mdsimon2]

Sorry to dig this old post up - but is there a way to reconcile the difference between the beocreate and minidsp's shelf filters. (Is what you're suggesting with the biquad coefficients?). New to all this! Am wondering how to translate a project with published miniDSP settings to work on the beocreate (like the Directiva active crossover).

Take the existing minidsp configuration and calculate biquads based on your desired filters using the spreadsheet linked on this page -> https://www.minidsp.com/applications/advanced-tools/advanced-biquad-programming or the Octave routine attached to this post -> https://www.audiosciencereview.com/...z-the-answer-for-home-audio.19774/post-652311.

Once you have the biquads swap the A1 and A2 coefficients when entering in to Beocreate and the response should match miniDSP.

Michael

 

[juliangst]

I haven't found many comparisions between the LXmini and 'normal' speakers.
How would they compare to something like LS50 with a sub? I bet they have much wider soundstage but how good is detail retrieval and imaging and general accuracy? How much power do the LXmini need when highpassed with a sub?
Are the really worth the build effort?

 

[MarkS]

Have you seen this review by Erin?

Linkwitz LXmini Speaker Review

Linkwitz LXmini Review

www.erinsaudiocorner.com

 

[juliangst]

Linkwitz LXmini Speaker Review

Linkwitz LXmini Review

www.erinsaudiocorner.com

watched it a couple of times but he didn’t do specific comparisons unfortunately

 

[Flak]

Have you seen this review by Erin?

Linkwitz LXmini Speaker Review

Linkwitz LXmini Review

www.erinsaudiocorner.com

Yes, it looks like they can take full advantage of a proper EQ thanks to a good directivity index.
Maybe a good solution for both crossovering and precise EQing could be the new miniDSP Flex with Dirac Live?

miniDSP Flex

Pocket size processor with flexible Input/Output configuration, Audiophile converters, 400MHz Sharc DSP processor, BT connectivity, DSP toolbox for subwoofer and multiway crossover, Dirac Live optional upgrade

www.minidsp.com

 

[juliangst]

Yes, it looks like they can take full advantage of a proper EQ thanks to a good directivity index.
Maybe a good solution for both crossovering and precise EQing could be the new miniDSP Flex with Dirac Live?

miniDSP Flex

Pocket size processor with flexible Input/Output configuration, Audiophile converters, 400MHz Sharc DSP processor, BT connectivity, DSP toolbox for subwoofer and multiway crossover, Dirac Live optional upgrade

www.minidsp.com

Only has RCA out and is a bit expensive unfortunately. If I decide to build this speaker I will probably get a topping DM7 and use it with camilladsp

 

[Rick Sykora]

Only has RCA out and is a bit expensive unfortunately. If I decide to build this speaker I will probably get a topping DM7 and use it with camilladsp

Minidsp Flex has balanced outputs as ordering option. Amir's review unit had balanced outputs as I recall.

 

[juliangst]

Minidsp Flex has balanced outputs as ordering option. Amir's review unit had balanced outputs as I recall.

Amir reviewed the version with 4 outputs which is available with RCA, TRS or optical/ coax.
The Flex 8 only has 8 RCA outputs