I haven't tried a Stax amp, so I can't comment on the sonic differences in this particular discussion, but I always find it interesting about people saying the stock amp doesn't go loud enough. Headroom is not an issue I have. I barely turn mine up a quarter turn (about 9 o'clock if it had an indicator) before it gets too loud for me. I guess I just listen quieter than most.
Yeah, as I have said in an earlier post, if you listen at low volume, then you may or may not hear a difference. I like my music loud. The stock system starts to break up at the volume I listen to but on a better amp, I can go louder than i can stand and the SQ is always clean and clear.
I recently purchased one of the cheaper Stax SRM-1 MK 2 units that were listed here - Birgir has a lot of junk laying around so don't be afraid to email him!
After finding a spare Koss cable and converting it to a Koss -> Stax adaptor, I had the unit + cable shipped to me for around $800 AUD. Not a bad price for a refurbished amp that honestly smokes the stock Koss energiser.
Received the ESP-95X back from Koss today; looks like they just replaced the entire unit so I'll be breaking the drivers in from scratch again.
That's what I love about the Koss ESP=950. They are the last and only headphone that they guarantee for life - no questions asked.
Instead of repairing the phones they always just exchange them for a brand new unit.
One of my favourite mid-priced amps is the Stax SRM -T1 (Vacuum Tube output).
However, the amp I'm currently using for all of my electrostatic phones is my coveted HeadAmp KGSS (built by Justin).
Enjoy your Koss!
Sounding so much better with the dekoni perforated leather earpads...
Also sounding better after burning in the drivers - Will try it for a full 300 hours and see if it really makes a difference.
Not as much low end as the HEDDphone + Eletech Inferno copper cable, and maybe just half a notch lower in detail (the HEDDPhone is the most resolving I've heard)
The ESP-95X has a more even treble, so it sounds a little bit brighter than the HEDDphone which can be welcome also.
Probably the phenomenon described above by milosz has something to do with why ESP-95X seems to sound better after about an hour of use and maybe also why they sounded awful when I first plugged them in. They need to charge. Amps I think also sound a little nicer after they warm up.
Are you guys sure it's the earphones that change their sound after an hour and not the E90? I remember actually preferring the sound for monitoring when it was first turned on, and then found them to sound more conventional after an hour or two of being left on. This seemed to occur independent of whether I was listening or not for that span. They'd go from being super tight, flat, transparent, great separation that could be easily heard even at low volumes, and with a high macro detail but limited punch, to instead being more flabby and less transparent like normal headphones, and trading macro detail for like micro detail. The punch was still not there, but that didn't bother me. The black background was suddenly populated with more stuff from the source, but the earphones also needed to be turned up more to get the original macro detail and sense of separation. Their flat response would slightly warm to become closer to the sound of the K701 & HD580 but just more extended, while still being delicate, and, again, still very detailed, just a different kind of detail compared to when it was first turned on. When first turned on, it was almost like a combination of interpolative upsampling harmonics were present that made sounds easier to latch onto and an extender processing the sound to hype the dynamics and macro detail in a very useful way.