barthman.de
Well-known member
I proudly present my finished G9 Tube Preamp. It took over a year to design the pcb's, front plate, get the components and build the preamp.
I made 3 PCB's for PSU, transformers and the pre's. All pcb's separate star-grounded. The cabling with the front-plate (pot's, Grayhill step-switches, switches point to point (seperate shielded). I have shield the 230V mains cable with metal braid too. Lundahl transformers, Siemens/Wima/Epicos-caps. Phase switch and Mic/Line switch with relay's. At first TAD and JJ tubes.
The preamp worked after first power up 8) After first check up: flat frequency response. 2k and 3k parts. No hum, no noise, sounds neutral. More later.
Here some pics:
I made 3 PCB's for PSU, transformers and the pre's. All pcb's separate star-grounded. The cabling with the front-plate (pot's, Grayhill step-switches, switches point to point (seperate shielded). I have shield the 230V mains cable with metal braid too. Lundahl transformers, Siemens/Wima/Epicos-caps. Phase switch and Mic/Line switch with relay's. At first TAD and JJ tubes.
The preamp worked after first power up 8) After first check up: flat frequency response. 2k and 3k parts. No hum, no noise, sounds neutral. More later.
Here some pics: