I have a akg k701. It is great at certain things, but bass is not one of them. So today I decided to hook up a subwoofer i had lying around the house along with my headphones. The results are amazing. The bass is deep and I can feel it instead of just hearing it. Has anyone else done this before...

  I recently build a CK2III amp. However I think i damaged the transistors, can anyone help me verify that the transistors are indeed spoiled from the voltages in green? The +15V and -15V test pads on the board are 15V and -15V respectively. There is no sound produced when i plug in...

Actually the 12v mod has been done before. So I am just wondering about the digital volume control. How does the T3D measure up to the D4?

I am interested in buying a iBasso D4 and am considering 2 mods. Firstly to mod it to 12v while on usb. And secondly to add a digital volume control. My rationale is that, the volume is unequal in both ears when the volume knob is in the lower one-third. Problem is that I'm going to use it...