@thyname I got a few headphone amps and kept 2.
Matrix Mini Pro 3 - this one is almost like a portable DAC/amp. At least it is easy to move to various room in the house or backyard. It also sounds pretty good, as do most $1000 DACs. That reminds me I need to help a friend set his mini up.
Benchmark BHA-1 - A bit too fatiguing so sold it. I loved the look of it though. This amp maybe nice with the Musetec oo5 DAC I have. I never tried them together.
Benchmark HPA4 - a great headphone amp and a great 2-channel preamp. I sold it by mistake, but I no longer needed the headphone amp part because I ONLY use RAAL SR1a and CA-1a phones. I ended up buying the Benchmark LA4 preamp to replace the HPA4. Though I made money on the sale of the HPA4. The HPA4 + old Meze Empy is great, not RAAL SR1A great but great in a headphones kind of way. The RAAL SR1a is a level beyond headphones.
Schitt Jotenhuim R + Sony SCD-1 SACD player - I have this in my second office room. I also have a Topping top end DAC hooked up to it. THis is used for the RAAL SR1a and CA-1a.
RAAL VM-1a - this is an incredible tube headphone amp solely made for the SR1a and CA-1a. I cannot imagine anything better than these 2 phones with the VM-1a. I use a neutral DAC with this amp, the Benchmark DAC3B. It is not as good with the smoother sounding Musetec 005 DAC.
I am building a Livingroom system and it has to sound as good or better than the VM-1a and the SR1a combo. Not an easy task.