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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?
tgonzales

Showing 5 responses by tgonzales

tgonzales OP
30 posts
 
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.
tgonzales OP
30 posts
 
P.S. you are completely right about the 1 ohms.  It probably too much even for the mighty Pass Labs.
tgonzales OP
30 posts
 
I'm driving them with Pass Labs XA100.8 mono blocks.  100wpc in class A and 200wpc in A/B.
tgonzales OP
30 posts
 
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.
tgonzales OP
30 posts
 
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.  
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