Actually i feel the case design is a little thin. But still much better than SR71a. Diablo got the best casing among all amps i owned
that being said I think it (the OEM) looks very cool in a utilitarian/industrial/edgy kind of way
any yes the knob is sweet.
have only had a chance to test it works for 5 mins, but at this stage all I will say is it sounds as big as it looks...actually much bigger. with LME49720HA and buf634 and JH13 and on low gain it does hiss a touch with no music playing though; less than lisa, but it still does. Its not worrisome though, will see if I can find an opamp combo that doesnt as it could just be the national chip. so i'll just leave it burning and get used to the sound a little while I prepare everything else for it. will post some pics tomorrow of the setup for the discrete buffers. still unsure of whether I will do the necessary modding to allow the bursons to fit or whether I will just be content with discrete buffers and the ability to power the finest opamp chips.
the buffers take bipolar input and output SE, they are a drop in replacement for BUF634 as well though, so its not totally necessary to have bipolar. but I could use OPA1632 (fully differential opamp, the one used in the buffalo32 sabre dac) which will allow SE input and output differential. if doing this I would have to wire direct to the buffer as I doubt the PCB is set up for bipolar signal to the buffer socket. with a couple of further mods I could have balanced output; love having a bipolar power supply to play with