New member

[Stephen C]

Hi all, I built a K881 Mk II back in December 1997 (best Christmas present). I was initially disappointed with the lack of bass, so upgraded the signal capacitors (to PiO) and the cathode bypass (to Black Gates), which improved the sound.
I retired from full time employment a couple of years ago, and have decided to spend some of my leisure time with DIY electrical projects. My first was a small single-ended amplifier with ECL82 valves (i had in my stash). This is based on Caledonian Audio amplifier PCBs, but with Hammond iron and a EZ81 valve rectifier HT supply with C-L-C reservoir and High Pass filter smoothing. I have left the heaters AC, and the hum is inaudible (after the valves warm up). . I have switches to select different output impedances, and Negative feedback on or off. The sound from this small setup is surprisingly good and I prefer the open sound with NFB off, although the measured frequency response is not as wide. I am looking for better output transformers.