I'm not here to fight and I don't care about SBAF or Schiit products either. If you query me you would see that i'm mainly posting on head-fi and local forum. I do listen a lot with headphones and ASR got me interested in L30/E30 which was my first upgrade from portable oppo ha-2 dac/amp.
I found an improvement over the ha-2 using my clears, but still listening experience was tiring, too forward. I could EQ annoying peaks, but that brought Clear's to the level of PM3 with faster and a bit more spacious sound. Tried to live with it, but appearing headaches pushed the final button. Sold them and upgraded to Utopias just to find them worse sounding than Clear. Started my mumblings about Focal company and returning my Utopias while one member invited me to bring all of my equipment and to the test.
What we only did is compared amplifier one with A,B,C,D headphones and then amplifier two. For second round we swapped dacs to give L30 Qutest dac (3V input to L30) and P1U/E30.
If we disregard the size on paper topping is way more powerful amp. Both rounds of testing were with similar results while topping did a decent job with headphone A it failed with B,C,D. Luxman P1U sounded good with all of the headphones and as well edged the performance with headphone A.
Now you can blame B,C,D companies that they made bad headphones which includes Arya,LCD2,Utopia,HD800 and say that only PM3,HD650 are good ones, but I'm choosing an amp that sounds better and could play with wide range of gear.
L30 does the job with easier to drive/warm headphones. In the tests where L30 failed, increasing the volume brought thinner/sharper mids/highs while leaving low frequencies behind. On high gain sound was getting even more out of whack. P1U kept everything well under control even pushed well above normal listening levels.
Another interesting catch while swapping between dacs with L30 I couldn't really tell the difference between E30 & Chord qutest dac, apart L30 playing more loudly when we set Qutest to 3V output, but P1U responded nicely to them. While Qutest had better imaging, a bit more detailed and airy presentation, E30 had more flat sound, with thicker bass. Even though E30 fell short in performance against Qutest, but it really stood nicely against way more expensive DAC and yes DAC's do sound different.