I was asked by a fellow Stereo Net Australia (SNA) member to assemble a bottlehead headphone amp named Crack. But I didn’t know that I was also going to have to paint the top plate and prep and finish the blond base. But wait, there is more. The member had also purchased the Speedball upgrade which consisted of three cct. brds. which work as a constant current source. Fortunately the member realised the amount of work involved and rewarded my efforts. Thanks.
The instructions which come with the it are detailed bit I would not advise this kit for a first timer, The cct. brds. are compact and require careful soldering. The rest is easy but still a fair bit of work. The amp came up well, sounds excellent. I would recommend the kits and upgrade Speedball. The amp worked well with my 32ohm DT770s but I feel may work even better with 250ohm or higher cans.