Awesome Demo of the Advantages of DSP and Active Crossover-Danville Signal Processing with Magnepan

[@MichaelAmster]

Great discussion. This is going to be a big trend to create active speakers out of top of the line components from the traditional speaker world.

[@HollisAudioLabs]

Thanks for stopping by the Danville Signal room for the Magnepan 1.7i passive vs DSP active crossover demo. The idea was started at CAF2023 when I modified a pair of Magnepan MG10/QR speakers with the two 4x8in open baffle servo subs using the standard dspNexus 2x8 DSP system that you heard. Glad you heard the differences!

[@innomax007]

Removing capacitors, resistors, and inductors from the signal path has tremendous benefits which are easily heard in this comparison.

[@nathankimmett8803]

Would love to hear this demo at Toronto Audio Fest

[@NackDSP]

I did a similar conversion to a pair of 3.7i speakers. The passive crossover was very low slope and the speaker had a very nonlinear response. With active crossovers a very smooth accurate speaker was created. I used the Hypex Fusion 503, as it has power limiting for each driver, crossover filters, whole speaker filters and FIR filters. A really great, powerful and compact solution with a minimum of cables.

[@fredthompson1279]

Great video and demo. This is a seriously good product and a reasonable price. And I agree, this is the wave of the future. This demo also turned me on to Lofgren. I searched him out after the presenter mentioned who was playing.

[@Langeloudspeakers]

The art of creating an excellent speaker lies in integrating different transducers. One of the factors contributing most to playback quality is reducing the portion of the acoustic spectrum shared between HF and MF transducers. However, implementing a high-order passive filter, while synchronizing various transducers and potentially correcting frequency response imperfections, introduces more problems than it solves. Conversely, well-executed digital management almost always leads to a significantly better result. Although it may not yet be fully embraced by audiophiles, it's just a matter of time.

[@Pierre-Leloup]

I've experimented quite a bit with improvements on my MG 1.7i's, other passive filters, PLLXO and active filters, and finally in recent years with digital filters and the use of DSP. I use Class D Purifi amplifiers and the speaker just isn't the same at all... You have to spend a lot of time making the settings, because the dipole radiation doesn't make it easy, but in the end you get a speaker that spoils all my visitors, adapted to your listening room and your sound preferences. And, you can listen to it, I've just posted a new recording done with my brand new microphones ;-)

[@supercompooper]

I love the work they are doing

[@ericelmore887]

I know all part on the Maggie crossover have been upgrade in the X model but I’m not sure if values or frequency responses have been changed, only the quality of all the parts being used is the change that was made. GR research kits do have changes being made to make speaker have a more flat response . But what I’m told if you order a GR KIT magnepan is happy to install it for you at a cost.

[@johnmarchington3146]

I have a pair of Acoustat SPECTRA 6600 electrostatics and wonder how difficult it would be to replace the crossover network in them with the polarizing voltage circuitry being part of that. With Maggies that isn't a problem, of course.

[@matytinman]

Great video!

[@willowwale2000]

These Amplifier and speaker cable makers would NEVER embrace this stuff, but they should since they'll be able to sell more amps and speaker cables, however, an active system would not require expensive cables anymore.

[@staceymangham]

I don't know why you think it wouldn't need good cabling because it's active it's just as important unless they have internal amps of course

[@bbfoto7248]

@@staceymangham I don't think he meant that the speakers don't need "good" cables anymore...only that they don't need to be Crazy Expensive. There are sh!tloads of excellent speaker cables that aren't expensive. I've compared a lot of them but the results are only valid when used in my particular system. FYI, keep your eye on Erin's Audio Corner as he will be doing Blind A/B/X cable listening tests with a special random A/B/X switching device that he has acquired. Should be interesting.

[@318ishonk]

Totally agree with this approach although I'm sure most end-users won't go beyond using an amp and room correction like Dirac or Roomperfect (and keep the original passive crossover in the speaker). Even the full active way of driving the Maggies still doesn't give them any punch, right? Or can they suddenly play a kick drum or snare with the appropriate dynamics?

[@staceymangham]

Im sure they w be heads and shoulders above the passive Maggie's, obviously with appropriate amplification, it's one of the big gains with an active system as long as there are no resonance in the room and speaker

[@iampuzzleman282]

Halle Berry got her kid back and just like your video there was a happy ending. I could talk to this guy afternoon about DSP

[@arthurfleck1554]

7:28 , 17:00

[@iampuzzleman282]

This is definitely your room. You should know your videos are competing with a Halle Berry kidnapping movie

[@CarlVanDoren61]

20.7s/2-Rel Carbon Specials JLA cr-1 active crossover Shunyata Python xlr's 😊 Fastest Gun in the West Go w 2-Rel T9x & K231 Sublime

[@emersonperin4109]

You guys are mixing up the term "active" to mean line level. An active crossover is not necessarily better than a passive crossover. The main issue is WHERE is the Xover. Line level out of the DAC and before the amps is the way to go. A passive Xover at the speaker (after the amp) causes all kinds of issues because of the inductor and reflexions back an forth. A passive line level crossover is a much more "pure" implementation (a 1st order uses 1 cap and 1 resistor - that's it! - per channel). An active crossover has SS and a bunch of parts - much more complicated. Of course, the passive Xover as I am mentioning will be custom to your speakers (the Xover frequency determines the value of the components) and actives are adjustable.

[@AudiophileJunkie]

Now, it's become customary to refer to anything that isn't a traditional passive crossover as "active". If you have to plug in the crossover to an outlet, it's "active" by contemporary simplistic lingo, but it's also worthwhile to know the nuances... as well as that it can be done with analog or digital methods.

[@staceymangham]

I'm trying to work out what you mean by Line level passive xover, as there is only passive in the speaker leads which is external passive but it's not line level, passive internally in the speaker, and active at line level,it has to go after the DAC if it's active, it can't filter the frequency before the DAC unless there is a digital xover, which I'm familiar with in car audio but the signal still has to come out of the DAC at line level, low, hi, or low, mid, hi and then to amplification of seperate frequencies

[@HollisAudioLabs]

The dspNexus 2x8 can go between the existing preamp and power amps to act as the speaker DSP crossover. Having higher number of poles per crossover, up to a 4-way allows better control of out of band signals to each driver to lower distortion. It can actually replace the preamp in systems as it has balanced line level inputs that can also do phono preamp gain and RIAA EQ for vinyl. The system sampling rate is 192KHz and becomes the DAC for the system as it has a USB2Audio input. We help customize the system for the customer to his speakers.

[@iampuzzleman282]

Aside from frequency Control with the crossover, does this system deal with voltage regulation within the speaker drivers ? and how does it replace what the original speaker stuff does in that area?

[@bbfoto7248]

@iampuzzleman282 With this type of multi-channel DSP, you are able to individually adjust (with very fine/precise control) ALL parameters of the loudspeaker's crossover network filters...and more. You are working with the Line-Level signal rather than controlling the higher voltage speaker level amplifier output signal. These types of "Loudspeaker Management Systems" (DSP) have been in use for decades in the Pro Audio world. Search for dbx DriveRack 480/482/PA/PA2, RANE RPM88, Behringer Ultra-Drive Pro DCX2496, and DEQX loudspeaker management systems, etc. I'm not sure about this particular Danville DSP unit, but most of the professional pro audio units have built-in adjustable "Peak Limiters" for driver protection (if this is what you mean by "voltage regulation"). Some have Dynamic Compressors as well. You are able to fully program & select the Input/Output Signal Routing (I/O routing matrix), choose any Crossover Type (Bessel, Butterworth, Linkwitz-Riley, Chebyshev, etc.), adjust Individual Levels to within +/- 0.25dB, choose any Crossover Center Frequency, Slopes (6/12/18/24/36/48), fully variable Phase, and usually at least an 8-band to 31-band PEQ...for Each Individual Channel! The output from each channel on the DSP is then sent via SE or Balanced line-level to an individual amplifier channel to power each driver (tweeter, midrange, midbass, subwoofer, etc.). With the DSP, you can make infinitely finer and more precise crossover filters for each driver, including notch filters, zobel networks, and AllPass filters that would otherwise either be impossible or incredibly difficult and costly to achieve with typical passive crossover network filters using a combination of inductors/capacitors/resistors, etc. There are currently 100's of models of Car Audio DSP and DSP/multichannel Amplifiers with very similar (and usually more) capability compared to this Danville Unit. They range from 6 to 16 output channels and a few also have Swappable DAC modules/cards for ESS or AKM DACs. And some have FIR filters rather than IIR filters. Google Search these just to get an idea: Audiotec-Fischer HELIX DSP Ultra S 12-channel DSP (high-end $1,600) Audiotec-Fischer HELIX V TWELVE MK2 DSP/Amplifier or HELIX V EIGHT MK2 Audiotec-Fischer BRAX DSP (VERY High-End $5500) Gladen/Mosconi AERO 8|12 DSP (high-end $1800) Audison Forza AF Bit DSP/Amplifiers (many different models) JL Audio TwK88 DSP JL Audio VX800/8i DSP/Amplifiers (many other different models in the VXi series) miniDSP C-DSP 8x12 v2 DL (DIRAC LIVE) Processor Alpine STATUS HDP-D90 14-channel DSP with built-in 12-channel Amplifier ARC Audio PS8 PRO DSP & Blackbird DSP/Amplifier ZAPCO HDSP-Z16 V AD-16GA/HDSP-Z8 V AD-8GA (Swappable ES9038 or AKM4490 DAC Modules, $2300+) In one of my high-end car audio systems back in the early 1990's, I was using a Sony Mobile ES CDX-C90 stereo head unit (has a Toslink S/PDIF optical digital output) combined with Sony's 8-Channel Mobile ES XDP-4000X DSP unit. This processor had 8 Burr-Brown DACs...one for each output channel, and 6 SE RCA inputs (Front/Rear/Sub) + 2 Toslink optical digital inputs. You could save & recall multiple DSP "tune" Presets (let's say one for engine-off/parked listening, and one with a bit more Bass & Treble to overcome road & wind noise while driving, or top-up/top-down in a convertible, etc. This DSP still holds its own in regards to SQ compared to many current home audio DACs. That system had a 3-way front speaker setup (Peerless XLS8 8" midbass drivers in the front kickpanels/footwells, 5.25" Eton/Diamond Audio Technologies DA 5.6 HEX midrange, & Hiquphon OW1 tweeters) with 2 small rear Pioneer TA-878 3.5" coaxial speakers for low-level differential rear fill (for improved soundstage width/depth/ambiance), plus Two Infinity Beta 15X 15" subwoofers in a 3.5 cu.ft. sealed enclosure (1.75 cu.ft. each). The Center Image floated just under the rearview mirror and the soundstage Width was beyond the outside tips of the left & right side-view mirrors, with Depth way out onto the hood over the headlights (with tracks that contained that information, such as the muted trumpet in Sara K's "If I Could Sing Your Blues", etc.). All to say that the HiFi/Audiophile world is incredibly late to the party, LOL. 😛

[@HollisAudioLabs]

The dspNexus 2x8 is a full DSP crossover system to bandsplit the signal to each driver. It has much higher slope filters to minimize the frequency overlap between the drivers to make them better able to handle the signal power they receive. This lowers distortion of the drivers since out of band signals are more controlled. The passive crossovers have low slopes that have wide driver overlaps that put more power into each planar than it wants to work with well.

[@ianbett3853]

Yay

[@MartinHAndersen]

It’s sad that you don’t have an easy to use software like MiniDSP I was ready to buy until I saw the software

[@AudiophileJunkie]

I use the miniDSP SHD and agree it might be more user friendly, but sometimes "different" isn't that bad once you get the hang of things.

[@MartinHAndersen]

@@AudiophileJunkie Have you tried designing a crossover using their software?

[@peronnikbeijer213]

This is a smart demo, because the Magnepan x-overs in general are poorly designed and also very poor quality. I own a pair of LRS's, and I upgraded them with GR-research x-over parts. Also ripped out the steel terminals.. That was like 300 dollars, but a big improvement. I think the x-option from Magnepan itself, for 2000 dollar plus is not worth it. Because the components are not that expensive, and you get the same values for the x-over. Then this fully active x-ver for 4000 dollar is a much better investment to my eyes.

[@CarlVanDoren61]

Had LRS two months, 1.7is two yrs Keeping speaker 🔊 upgrade, yes Next stop: 60" true ribbon tweeter

[@CarlVanDoren61]

Downside sonic digital 😮 DSP adds to this dilemma Use Path Audio 1.2R 10w level out 60" ribbon tweeter JLA cr-1 active crossover 2-Rel Carbon Specials Coda Ts v3 800w@4ohm

[@bbfoto7248]

NICE. But the paradox and conundrum is that 90% of the music from the last 10-15 years or so that you & I actually listen to was Recorded, Mixed, and Mastered using Active, DSP + internally Amplified Studio Monitors. Yet most "audiophiles" would scoff using such speakers (with built-in DSP & Amplifiers). And before that, Bob Clearmountain (and MANY, MANY other highly respected engineers) mixed some of his most iconic songs and albums using cheap Yamaha NS-10M passive monitors for a fair bit of time, which were originally produced as inexpensive "HiFi" bookshelf speakers. The NS-10 were just $375/pair in 1998 just before they stopped producing them, and the amplifier of choice to power them at the time was a Bryston 4B or similar Bryston model. Until recently, I was using the active ATC SCM25A until my own DIY 3-way concentric mid/tweeter design with DSP and Hypex Nilai500-based amplification replaced them for about 1/3 the cost while clearly outperforming the ATC. The vast majority of Studio Monitors that are currently used by Tracking, Mixing, and Mastering Engineers are Active/Self-Powered with many incorporating DSP along with their own mic/measurement/room correction software or mobile app. So the question remains: Which is more important, the speakers used to produce the music, or the speakers used to listen to that music? 😛

[@cudfoo1cudfoo247]

Looks like the 1.7i shrunk. That looks like the LRS not 1.7i...

[@cudfoo1cudfoo247]

Maybe it's a wide angle lens or that guy is 8 ft tall