How good is the crossover in your loudspeakers?

I have been a GR follower for some time and did choose to install the Magnepan LRS+ kit of parts he sells and I'm happy with the result. Better top-end, more definition  - just  "nicer" to listen to and no more $2 fuse in the signal path. It is no secret that Magnepan choose to now offer most of their range in an "X" version, with vastly improved (and costly) crossover components, so it seems both see a market for these types of upgrades.

As Danny points out and I'd tend to agree - many companies build their speakers to a price point, and a glossy wood grained exterior seems to sell better than a fancy crossover - the latter often seems to get the accountants eye the most. Even a cheap but well designed crossover can measure good, but a simple measurement does not have anywhere the discernment of the human ear. 

A good quality crossover can significantly increase the cost to build in a cheaper speaker and this is why we often get what Danny refers to as "cheesy" parts.

I'm on the side of better parts matter - not all will agree of course!

For about a week I’ve been down with a serious bout of a rare form of migraine headache known as a "cluster" headache (I started getting them forty years ago). Imagine getting a bolt of lightning to your brain, and waiting for the next one to hit. Sometimes it’s in a matter of seconds, other times minutes. My clusters usually last about three days (most often starting just above one ear, making it’s way across my head to the other ear), this time the longest ever. The prescription drug I take usually helps, but this time didn’t. People have been known to commit suicide to end the pain of their clusters.

Anyway, catching up with this thread has been for the most part delightful; lots of great comments from knowledgeable, informed audiophiles. As for the others, oh well.

As others have already said, upgrading the crossover in your loudspeakers can be done without resorting to buying a kit from GR Research. And if you like a deep hole in the frequency response they may produce (due to two drivers being out-of-phase at the x/o point, or as in the original version of many of the Klipsch models, the woofer and tweeter not even reaching each other until their respective outputs have dropped way below the mean response of the speaker), that is of course your right. But to call that defect a "voicing choice" is just silly. What it really is, is poor engineering. Klipsch corrected the poor x/o filters in the Mk.2 versions of some models. That is not a matter of a natural evolution (or tighter parts values control), it is correcting a mistake. It was obviously done in response to Danny Richie’s evaluations.  

There is no doubt that Magnepan’s introduction of the X Series versions of their models was also made in response to Danny Ruchie’s evaluation of a few models. I mean, Magnepan has been making all their models with the same crossovers since 1970, the X Series upgrade appearing only after Danny’s videos aired.

Here’s something to consider: I don’t know the prices, but it could be that the GR Research upgrade kit for the, say, Magnepan 3.7i, might be about the same price as the cost to get the X Series version instead of the standard 3.7i. But here’s the deal: Magnepan uses all better parts in the X crossover, but the x/o filter characteristics are no different from those in the standard model. It in no way "corrects" the problems Danny Richie found in his examination of the 3.7i.

What problems, you ask? The same problems John Atkinson found in the last Stereophile review of a Magnepan he did, decades ago. Magnepan has never sent another speaker to the mag, Wendell Diller saying it was because Magnepan’s can’t be measured like other speakers. Both Atkinson and Richie found the drivers played "over each other", a result of the shallow x/o filters and the chosen crossover frequencies. That creates serious problems of comb filtering, a phenomenon known to speaker designers for many, many years. It’s a testament to the quality of the Magnepan planar-magnetic drivers that the speakers sound as good as they do in spite of the flaws in their crossovers!

The beauty of the old Maggies (like the 3.6) is their series crossovers. With a good active crossover (like the First Watt B4 I mentioned earlier), you can create your own filters. I don’t remember what filter characteristics Danny came up with for the 3.7, but with a x/o like the B4 you can try 4th-order low- and hi-pass filters at 400 Hz. If you don’t like it, try something else.

Or, you can just buy a pair of Eminent Technology LFT-8c’s. A single push/pull planar-magnetic driver (magnets on both sides of the Mylar diaphragm) for 180Hz up to 10kHz, a ribbon tweeter for 10kHz up, and a dipole woofer for 180Hz down. Wendell Diller has been insisting forever that a monopole woofer "does not work" with a dipole loudspeaker, and Magnepan has been working on a dipole woofer system for a number of years. Why so long? No need to wait any longer, Eminent Technology already has one.

Or even better, add to your dipole loudspeakers a pair of the unique OB/Dipole Servo-Feedback Woofer that Brian Ding of Rythmik Audio and Danny Richie collaborated on. Open Baffle (2 or 3 12"  woofers in an open baffle frame), dipole output, and servo-feedback control of the woofers. It will play up to 300Hz, unique for a sub. It comes with a plate amp that contains a dipole cancellation compensation circuit, and all the controls you want and need, and in the analogue domain.

@bdp24 Very well said summary.  For a DIY person crossover modifications or going the amp for each driver route would not be difficult.  If one can't handle a soldering iron, stay away from DIY.  

Passive crossover or all active can result in a system that measures well.  Measurements do not tell the entire story.  For those of us that have over the years tried many of the latest bright shiny audio gizmos or idea we know that fact all too well. Separate amps for each driver is nothing new and revolutionary.  There are trade-offs for any approach.  

Claiming an all active system to be superior is a broad generalization, not a universal truth.  Previously noted potential problems cannot be explained away by opinion.  Parts count increased by dozens and more interconnections decrease overall reliability and introduce new variables.  That is engineering fact that can be calculated.  When a complex system works it can be great.  When a problem appears, it can be a nightmare.   

Wendell Diller has been insisting forever that a monopole woofer "does not work" with a dipole loudspeaker, and Magnepan has been working on a dipole woofer system for a number of years. 

Well maybe with Magnepan speakers but otherwise the statement is misleading. I've heard a number of implementations of dipole speakers with sealed and ported woofers and in those instances it was clear the combination can work.

@texbychoice wrote:

Passive crossover or all active can result in a system that measures well.  Measurements do not tell the entire story.  For those of us that have over the years tried many of the latest bright shiny audio gizmos or idea we know that fact all too well. 

Nothing new here (either). 

Separate amps for each driver is nothing new and revolutionary.  There are trade-offs for any approach.  

Right; active config. is nothing new nor revolutionary (nor is passive bi-, tri- or more-amping over speakers with existing passive crossovers, albeit a more well-known approach among audiophiles), but you could say that of other design choices that, while advantageous, are not generally implemented. Practically speaking the only trade-off with active is a higher electrical bill from the multitude of amps. 

Claiming an all active system to be superior is a broad generalization, not a universal truth. 

True, but with a proviso: there aren’t that many opportunities to make an apples-to-apples comparison between actively and passively configured speakers, because it’s about assessing a typically bundled active speaker design of one particular brand (usually with built-in Class D amps and a consideration for minimizing cost here) with a passive speaker design of another brand with a wildly varying combination of amp choices. Basically you’re left with buying into comparing completely different scenarios that aren’t that easily comparable coming down to a single aspect alone. 

To really assess the potential of active config. take the same speakers, strip them of their passive crossovers, add the required amp channels using a similar amp as the one used passively as a basis, add a high quality DSP, and have fully optimized filter settings implemented, aided by measurements and completed by ears from your preferred listening position. Then you’ll have a more true bearing, and in each of these cases and specific context where I’ve heard this happen, the active approach - not only to my ears - won by a mile, hands down. And what do I mean by "won by a mile"? A much better resolved, more dynamically astute, more transparent, more transiently clean/less smeared, more effortless, and tonally a more accurate and authentic presentation. 

Besides: my main intention was to point at the amp to driver interfacing, and how active wins out every day here. This is not debatable - indeed it’s a damn fact. With any design however there are many choices to be made, and the totality of those will determine the outcome. My advocacy is for outboard active configuration, because this way you can go about it more or less as you see fit - like you would passively. If however a preassembled and -designed bundled active speaker fits your bill and hits a home run, then you may have come by your solution all that much easier. 

Previously noted potential problems cannot be explained away by opinion.  Parts count increased by dozens and more interconnections decrease overall reliability and introduce new variables.  That is engineering fact that can be calculated. 

Come on. Let’s say you buy two more power amps similar to the one you already own for a 3-way active setup, add a high quality DSP (while stripping the passive crossover) and some extra IC’s and power cables - you mean to tell me you’d now have trouble sleeping because of reliability issues? Well, if you insist on placing obstacles in front of you to avoid going active or otherwise adding a few components (or just to be willful), by all means. But essentially the same could be leveled at those who’re buying a turntable with all that involves, a separate preamp, mono block amps or other. Like you said, measurements don’t reveal everything, and the same way holding a rigid stance on component count and how it pertains to sound quality and reliability can’t ever be the whole story.