Magnepan 3.7i with two (2) DWMs with Pass Labs XA100.5

I recently upgraded by speaker cables between my Pass Labs XA100.5 and Magnepan 3.7i and a pair of DWMs. I've tried connecting the DWMs both in parallel and in series (using the DWMs crossovers).  I moved from Kimber 12TC to Audience Au24 SE.  This change added more detail and transparency.

Interesting when running in parallel (i.e., the 3.7i and DWM each connected directly to one of the XA100.5's two connections), the XA100.5 quickly left A-class.

Having the each cable around and given the nature of the DWM, I tried running the system both parallel and in series on the same system.  In other words, I was using all four sides of the two DWMs.  I wouldn't say that the XA100.5 couldn't handle it (opinion welcome, read on), but it was quickly out of A-class.  The meter would swing back and forth.  The interesting thing, is that I lost the Pass Labs sparkle.  Bass was very powerful and could be felt.  Yet it was almost muddy for the loss of a better word. Was the loss of mid-range magic, the XA100.5 running out of steam?
Hi tgonzales,

I too have 3.7i's and DWM's. Some questions, as I got confused on the details.

By parallel, I think you are stating that you run one set of wires to the main speakers out of one set of taps and you run a second set of wires out of the second set of terminals.  That is how I have always run my DWM's. 

When you say "series and parallel" in the same system are you saying you ran a set of jumpers from one half of the DWM to the other half? Wouldn't that imply a 1 ohm load? Or have I Misunderstood?

the only time I have used both sides of the DWM at the same time is when I run a single one, in which case I connect the right channel to half and the left to the other half. (For those not owning DWMs this gives the volume of two DWMs with a single unit, but restricts placement options). 

I will say that even driving half the DWM out of the second speaker taps can result in muddy sound in my system. It is easy to get too much lower midrange and too much upper bass (I have never heard ANY benefit below 63 hz of using DWMs). They recommend placing the DWM 10 inches loser than the mains, and this does help, but I suspect it also messes up the coherence of the back waves, which are now clearly lagging (by my thinking if the front wave is lined up ten inches closer then the back wave is off by twenty inches?).

two things which I have found help. First is I use resistors to lower the output of the DWM, and second I find that I can get less bloat in the bass by running them exactly parallel and on the outside of my mains. Since my mains are pointing directly at my ears, the DWMs are effecyively the same distance. This tightens the bass up, but does not always work, as I can sometimes get peaks (depending on where my main speakers are in the room). 

How do you have yours placed in comparison to the mains? Are you using resistors or attenuators? 

Thanks for your response.  Yes, you are interpreting my set-up correctly.  By parallel I meant one tab of each mono-block to the main speaker and the other tab of the same mono-block to the DWM.  By in series, I meant one tab of each mono-block to the DWM and then via the cross-over out to the main speaker.

I have tried the resisters (attenuators) recommended (sold by) Magnepan when I ran the speakers in parallel.  I felt the bass was a bit rolled off for my room.  On the other hand, when I didn't use the attenuator, I felt that the sound staging was a bit confused.  I think the DWM were voicing a bit too high.

The best set up for me so far has been running them in series without attenuators.  (I'm sure that the DWM's cross-over its up to snuff but it still sounds better.)  I have tried the DWMs in between the 3.7i's, about 12 inches in front of and 12 inches behind the 3.7i's.  Currently, I have them behind the main speakers because it makes it easier to both assess my turntable (which is against the back wall) and the LP rack (which is against the side wall). 

As mentioned in the original post, I changed the Kimber Kables 12TC for the Audience AU24se.  This really helped.

Thanks again for your post and thoughts.
P.S. you are completely right about the 1 ohms.  It probably too much even for the mighty Pass Labs.
What size is your listening room? As I have a 18x21x12 room and also purchased the DWM panels but found with my setup it sounds better without the base modules. Mine you I use a tube amp with 195wpc.
Maggie tech and bass just doesn’t compute.  If you must use Magnepan speakers, use REL subs for a more musical and impactful sound...and they don’t screw up your systems sound.
My listening room is a touch smaller 15 x 21 x 12.  I found the panels were very musical but did not offer bass extension nor feel.  I ultimately replace them with a pair of JL Audio F112 v.2.  The JL Audio are a trade off.  The backbone of music is powerfully conveyed tunefully and forcefully, but it feels at times at the detail/sparkle suffers.  The soundstage is deeper for what that's worth.   In the end, the Magnepan sound is more a wall of sound than monitor precision and the subwoofers add the octave and power to that the 3.7is lack.  With that said, the two presentations (3.7i alone or augmented) could easily be enjoyed.  Different rather than categorically better.

What are you using to drive the Maggies? I have a similar size room and a pair of 20.7’s that I recently upgraded from 3.7i’s and I didn’t need a sub then nor do I need one now. And get this I’m currently driving them with 95wpc tubes. I honestly believe it’s in your speaker placement. I suffered through lifeless music with my 3.7i’s for almost a year and then I read the manual and dialed in the placement and got immediate gains. To the point that I’m either going to sell or trade the DWM modules. I also replaced my ARC solid state mono-block amps 600wpc in 4ohm with PrimaLuna Dialogue Premium HP amps. A Wall of Glorious Sound!
I'm driving them with Pass Labs XA100.8 mono blocks.  100wpc in class A and 200wpc in A/B.

Play with the placement and I’m certain you will see the 3.7’s go to an another level of deph and dynamics. Also make sure if you have the tweeter on the inside that the panel is closer to your listening chair then the tweeter. The tweeter must be further away from you for maximum imaging and openness. As I’m sure you are aware Maggie’s are finicky when it comes or placement but once you get them dialed in the rewards are incredible. Happy listening and cheers 
Yeah, the way you have them wired you are definitely putting a strain on those monos.  I have the 3.7s and used to run them with a Pass 250.5.  Tried the DWM's and never did get used to them. Tried several subs (some pretty expensive too) and just couldn't find the right integration.
Finally tried an inexpensive Martin Logan and it was great.  Non ported and built to work with ML Electrostats so it was fast enough and very accurate.  I never looked back.  BTW..... Just a quick note.  Take out those steel jumpers on the back panel and listen for a very large change in detail and dynamics.  I happened to use Anticables but anything is better than the steel. 
The combination of a 3.7i and DWM on each XA100.8 pushed it. It would occasionally leave class A. Now with the JL Audio F112 "driven" directly from the pre-amp, this is not a concern.

The XA100.8 rarely leave Class A now, but ultimate SPL can only reach loud rather than "unneighborly." I was surprised that the change from XA60.5 to XA100.8 barely impacted ultimate SPL and transition between A and A/B.

Mine had upgraded the fuses, jumpers, and stands (myestands) when I first bought them.  So I didn't have the chance to appreciate the difference.