Up for sale my Apex Pinnacle. Upgraded with Osram B65 tube ($1000). This amp is the successor of TTVJ 307A, and claimed to be the best amp for R10 by many users. As during my humble experience in head-Fi, it's also the best headphone amplifier for non-electrostatic headphones, I believe David Mahler uses this amp for his R10s when he wrote his legendary flagship headphone reviews. It is also a very good amp for other phones, as well as an exceptional preamp. It can be set as 115v or 230v.
Price $6900, the only trade option is BHSE+cash at your side. Pinnacle 2 and ultra pinnacle are released. MSRP for them are $12000 and $18000, and they don't have dual 3 pin XLR headphone output. You've got a bargain buying it at my listing price (consider there is no major upgrade for the new pinnacle).