Stax Lambda Pro Headphones--Can sound Hard??

I bought a used pair of Lambda "Pro" phones with SRM 7 box. They sound very good and generally better than every dynamic phones I have tried, but also sound a bit "hard" in the high frequencies,. I only occasionally use them, so I don't want to sink any big bucks into "mods" or expensive interconnects. I have them wired to a McIntosh 1700 receiver speaker outputs to avoid hooking the transformer box to my amp. I also have a cable running (Audioquest "Coral") from my preamp to listen to CD, tape and Turntable. Any suggestions on improving the overall sound, and eliminating the "hardness" Thanks, Jim
I have the same headphones and amp. They are very revealling, and if anything on the front end is at all harsh--you will hear it. I did use some Audio Purist interconnects, which I feel tame them a bit, but it is still right on the edge. These are not polite headphones, they are used in the recording industry because they do reveal so much--kind of double edged sword.

Audio cables are not tone controls!You need to change your current SRM-7 box,for a truly Stax class A amplifier.These ordinary Stax box are not in the same league.

Good luck
I would agree with the last comment. I have had the same Pro Lambda's and the accompaning "box" for over a decade now. Whereas they are incredibly clean and revealing (at least with my passive pre and forte 1a power amp) they are a bit hard as you say and I believe this is due to the transformer box. The way to go is to get the stax class A tube amp made for these headphones and connect your pre directly to the stax tube amp. Having your stax headphones going through a McInstosh receiver could only make them 'harder' sounding.
I have a pair of Lambda Pros also and listen through the SRD-P portable transistorized amplifier. Yes these phones can sound harsh at times but for revealing detail they are unsurpassed. As Famaraca says the Stax Class A amp is the way to go.