Re: Phono II and III 3.18 time constant resistor value.
Following on from my post 7, I have a second Phono III populated board with stock components including the 14K3 resistor at R21-22, using the same valves and power supply, the scope trace was almost identical until just after 5K cycles, then there is a rise to just under 4db all the way to 15K then another rise to 20K, no wonder it sounded too bright. I also expected more interest on this subject and I am very disappointed in the lack of positive communication, only Matthew expressed interest and I do hope he changes future sales of Phono R21-22 to the correct value, as for the bypass capacitors, why did WAD remove them ? I think I know the answer and 5751 valves will again change the RIAA equalization. Bob
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