In my new WA5 I used for arround 25 hours the stock Tubes with the HE-6 at the K1K output and it sounds ok. It was interessting before I hear the HifiMan with my Bryston and it seemed to me that there is not enough power to drive the HE-6 to perfection. Totaly different is the Woo to my ears it sounds with the stock Tubes better than the BHA-1.
After this first short burn in process I swapped in the SERP's, the Cossor 6SN7GT and the Brimar Rectifier and I was a litle bit disapointed. I read a lot about the SQ from the SERP's and I use the Brimar in my WA6 and I like it very much so the Cossor must be the Problem, I changed it to the stock Sylvania and it was much better. I hope the Cossor will be much much better after Burning in process if not is was an expensive experience. Im use the WA6 for burning in the Cossor.
At the moment I use the Psvane T2's in the WA5 there have only 50hrs on it and I think they need a lot of more hours.
I really think that the WA6 is very good amp and I like the sound with my HD800 but the WA5 is to my ears a big step forward and I only can imagine how it sound when everything is fully burnend in
At the moment I am sitting in armchair and enjoy some singer and songwriter music.
I did the HE-6 regrilling and the Audeze vegan Pad mod so far. I bought felt for the Fuzzor mod but I think is the wrong material it is not stiff enough I have to look for other one. But this two mods sound very good to my ears and the new pads are very comfortable.