Crossovers, why so few options?

Jim S,

In an attempt to get the most out of my modest system of Magneplanar 1.6's and older Arcam electronics I gutted the 1.6's of the passive crossovers, rewired them, and inserted a Bryston 10B. The change was truly transformational in all the ways you describe. A lot of hard work (and apprehension for someone who had no experience in this kind of thing), but worth it.

A good friend who is a reviewer for Absolute Sound owns Maggies and like you, went all active on crossover. He hears very well and I respect his opinion.

Several well respected, super expensive speakers have passed through his listening room and the Maggie held their ground. I don't doubt you are getting the results you claim, active done right solves problems we didn't know we had, until after the fact.

AP,

It is still a modest system, and not "perfect" by any stretch, but it is amazing the difference going active made. More control, more transparency, more headroom for the little amps.

You said one thing that I think especially pertains to Magnepans;

"Some speakers have a threshold that must be breached before dynamics and realism come into play and frequently that window is shallow, with high sound pressure levels becoming blurred as you push the envelope."

The speakers are in a large room (30' x 60' irregular) and you could hear the strain as I would try to push the SPL's to the point where the music came to life with passive speaker level crossovers. Night and day difference going line-level active.

I need to give credit to the guys over on the "Planar Assylum" for documenting how to go about it. It is not a plug and play thing with the 1.6's. Your descriptions as you went through the development of the crossover for the Mega Lines was also an inspiration.

Jim S.

The MG 1.6 crossover is a simple HI/LO divider and has none of the extra elements that Kal refers to. It is, therefore appropriate to consider for biamping. However, the stock crossover does have different break frequencies and slopes for the HI and LO sections. If this is not duplicated performance may be degraded (or, perhaps, improved).

Eldartford,

Nice to talk to you again. You're correct about Maggies and the assymetrical slopes and frequencies. The Bryston gives just enough adjustability to pretty closely match the stock settings and experiment a little with different combinations. I dabbled a little with measurements to let me "visualize" what I was hearing. Two observations:

You can make different combinations of high and low pass slope settings (with frequency adjustments) measure the same, but the presentation is different. I am no "golden ear", but it is really obvious to me.

"If this is not duplicated performance may be degraded (or, perhaps, improved)."

I actually prefer symmetrical 6db slopes (1st order) with the active crossover. The sound has more "clarity" (for lack of a better term). For my room and tastes, I prefer a different setting from "stock".

Jim S.

Stilljd...Experimentation is always interesting. I have not biamped my three MG1.6s unless you count the Subwoofer/mains as biamping. I did rebuild the passive crossovers using AWG10 air coils that are externally mounted. Because my Maggies will not have to handle SW frequencies I figured that the woofer panel could go a bit higher. My Woofer/Tweeter crossover break is about 250 Hz higher than stock. By the way, this saved a few bucks on the three AWG10 inductors, and the tweeter capacitors. I am well satisfied with the result.