**HELP** FOCAL ELECTRA 1028Be sound issue (muffled)

That preamp and amp date back to the mid to late 1970s. Have you ever had them serviced? That's what severe crossover distortion sounds like when the amps semiconductors hand of the A and B part of the signal to one and other. Probably something a qualified tech could easily fix and you might have to have some electrolytics replaced in critical areas. Hope is not lost though.

It’s been a minute but I had those speakers, I ran them with a Parasound A21, Primaluna Evo 400 integrated, Coda CSiB integrated, Krell 300xd Amp / Krell Illusions ii Pre.  The 1028BE’s didn’t sound at all dull with any of the amps / pre combo’s.  I ended up moving on because they actually were to intense in the upper regions depending on the track.  Hard Rock could be fatiguing.  Something either with the speaker, hook up or the Amp / Pre isn’t right.  With the BE tweeters, hard for me to imagine they would ever sound dull.  
 

Advice to have a local dealer give them a listen / look is great advice, also having your electronics serviced, bias checked.  Could be the gear or the crossovers in the speakers but as someone else commented, for both speakers to be dull sounding, that would be highly unlikely, points more toward the electronics.  These speakers were efficiently rated but they sounded better with current, not nescesarily Watts for days but with an amp that put out current that can control, drive the woofers, components.  

I would ike to thank everyone who contributed and tried to help with my issue. I decided to go to a local dealer and listen to the speakers, and decide from there. My amplifier was updated, with caps, and some transistors replaced. It was done by a great technician recommended by many audiophiles. I will take the small steps and see where this will lead me. I don't want to start spending thousands to replace the amp, cables, etc. I will advise about the results once the issue is found and resolved. Thank you again for all your feedback and advice. I truly appreciate this great community.

Good plan. Test... remove that variable, then test the next most likely... etc. Until the offending component. I would recommend spending no money until you are 100% sure that is the offending component. Starting with the speakers sounds like the right move. 

Don't think your amp is up to the task. Those speakers can dip below 4 ohms, not many amps from the 70's are comfortable with that. If all the drivers are working, its gotta be the electronics, last thing those speakers are is dull and muffled.

Former owner of 1038's. Happy to say former...