Thursday, 5 June 2008
Excellent link and description of a tube phono preamplifier. This design is quite well documented and has been through some 20 iterations by the designer/author since 2000. This appears to be someone who is not just designing by paper, but also iteratively refining the designer after auditions and contemplation. The design uses a lot of irons and uses D3a and 5687 tubes. Another interesting design is coming by Andrea Ciuffoli. He seems to be updating his site with regards to vinyl stuff quite recently. His' Phono 2 design makes use of all D3a tubes, and appears to be a relatively straight-forward design with a passive EQ. It appears from many of the sites that I have read, is that the power supply quality is very important. Above and beyond these designs, I have ordered a simple Bugle PCB from Hagtech. This is a battery powered OPAMP phono stage that is simple and cheap to implement. Should provide a good 'sanity check' reference to the more exotic (and expensive) options. Continuing to explore.