| Name | Function | Status | Info | |
 |
|
|
|
|
| Audio Research PH2 | RIAA - MM amplifier | |||
| FFI Pre-amp | RIAA, Buffer & Phones | Not finished | Several designs put together | |
| Hiraga Pre-amp | Moving coil pre-amp | Works | 2-transistor design | |
| Kaneda Pre-amp | RIAA & tome controls | Not finished | ||
| LM 318 RIAA | Low noise based on LM 394 | Works | Application notes AN-299, LB-52 | |
| Mic amps | Microphone pre-amp | Works | Symmetrical, based on Elector design | |
| Misc preamps | Several designs | |||
| Mixer 01 | Mixer w/Effects send & return | Not built | Stellan Lehrberg -99 | |
| Roy Hansen amp | Bass & CD input, phones out | Works | ||
| Simple MC pre-amp | MC head amp | Works | Sounds good. WW design idea. | |
| Siren Preamp | Tube based | |||
| System A Pre-amp | MC & MM RIAA pre-amp | |||
| Tone Controls | Parametric & Wien Bridge | Not finished | Application note OA-26; active filters | |
| Unknown | Microphone? General? | |||
| Walkmix | 5-ch portable mixer | Not finished | JJ & mg design - LM833 Appl note | |
