My New Magnepan 1.7i's sound dull and lifeless on the top end...why?


First time Magnepan owner - 5  days old 100+ burn-in hours on them
Associated Equipment:
-Denafrips Terminator Plus
-Holo Audio May KTE version
-Pass Labs X22 Pre-amp
-PrimaLuna EVO 400 Pre-amp
-Pass Labs XA100.8 Monos
-PrimaLuna EVO 400 Monos
-AntiCables interconnects and speaker cables
-Stock tweeter attenuator jumper replaced with AntiCables level 5 spade jumpers on the 1.7i's

My spectrum analyzer indicates both speakers highs are falling off beginning at 1.25K and are 9db down from 2.5K on
Been playing around with speaker placement and room treatments for 2 days now without any remediation. What am I missing? Suggestions appreciated.
128x128nayls02

Showing 1 response by charliech

@kingbarbuda "Magnepans NEED subwoofers. They do. They are ribbon speakers with no air movement and no percussion. There is no slam. They need subwoofers. I added a pair of REL T/9i subs to my 1.7i and it revolutionized the sound."

Can you elaborate how you connected your RELs to your system?  Did you just set the crossover on the subs?  If so, what did you set them to?  Did you do a high pass filtering on the 1.7s?  I have some 1.7is on order and want to have two subs as well and am trying to figure out the best way.  

Right now, I have MMGs and I'm using a Bluesound Node and it's sub out with a single sub (and its high pass filtering and low pass filtering) to connect everything, and it sounds pretty good to me.  But I want to have two subs with the 1.7s.  Thank you.