My LZ-A4 arrived yesterday - 3 days from China to my door in Seattle, WA. That was fast! My first opportunity to give them a listen was this morning. I started off with the installed filters (black/back - blue/front) and was startled by the clarity and detail. I listened for an hour or so before deciding to try the red front filters. While these sounded fantastic I found myself missing the extended treble with the blue front filters. I went back to the blue front filters and installed the red back filters (10Hz-35KHz) and this is where I landed. I've been listening to them most of the day without discomfort or any listening fatigue. They just sound so natural, so... right. They remind me a bit of my beyer DT1990 Pro's with the 'balanced' ear pads installed. Color me happy!