Hello, I just built a elekit TU-8100 with its included PCL86 tubes. SOunds pretty good with my Martinlogan LX16 speakers, so I was wonder hw it would sounds with headphones. I made a banana plugs to 4-pin XLR adapter and gave it shot. The amp is rather bass anemic with headphones. Might be the tubes need to burn in. Might be the PCL86 tubes in general. Might be the amp just doesn't work well with headphones. I'll burn in the tubes, and see if that helps. Normally I can't hear much difference between amps, but I'm pretty sure I can hear less bass. I'm curious on thoughts on using this amp as a headphone amp with the adapter, although I will likely use it as a speaker amp. Also, I'm curious if anyone has compared PCL86 and ECL86 tubes. This amp has jumpers to allow me to switch. ECL86 tubes aren't cheap, but are they worth it?