For my Grado cartridge I wanted a serious tube-based RIAA phono amplifier. With the (power supply) knowledge from earlier projects I wanted again the power supply external. And all needed voltages were given their seperate powerline: rectifier - snubber - coreless coil - first capacitor - choke (then an umbillical to the actual amp) - second capacitor.

The audiopath: XLR/RCA in - 6C45 first stage - passive RIAA - 6C45 second stage - interstage - 6SN7 - output transformer.
Even in the phonoamp itself most of the space is used for the final capacitors of the power supply. The actual audio line is only the middle part. The result: very dynamic; serious bass.

Very important were extremely stable components in the RIAA. I found out that Caddock resistors were really stable and sound well. Also after prolonged heating by nearby tubes.

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