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This is the top view of the RIAA board built on Radio Shack perf board. I used the tube shields during the prototype phase but they are not needed in the finished preamp since the tubes are mostly below the top plate of the chassis.

On the underside of the RIAA board you can see the AAA batteries for biasing the second stage. Note the copper strip in the center of the board. This is the common grounding point for the preamp.



This is an early version of the prototype. In this incarnation a 6SN7 was used for the line stage. Without shielding the prototype was a lot quieter than I had expected. It was ugly but sounded just fine.



Here is the underside of the top plate. Note the wood strips attached to the top plate with 5 minute epoxy. The circuit boards and mounting plates for the tube sockets are attached to these wood strips with wood screws. This makes for a clean look without any visible screw heads on the surface. I also found that the wood strips did a lot to damp resonances in the top plate.



A shot of the cutout for the input selector and volume control. The woodwork for this part was tricky and it took a couple of attempts to get it right. The wood is black walnut that was grown on my dads property in Oregon. Some of the nicest looking walnut that I have seen.



A view of the partially wired line stage. Note the grommets used to mount the aluminum and also the Moratite rope. The 26's are quite micro-phonic so I wanted to provide some isolation and damping.


In the other end is the power supply. I used a line filter card from an old printer to cleanup the AC.


The underside ended up being a bit crowded with all of the parts installed. The circuit board in the power supply section has the four DC filament supplies. Just to the right of the RIAA board are the oil caps inserted into holes in the top plate. To mount the caps I just used generous amounts of hot glue. Since the caps are short the hot glue seems to be adequate scheme for holding them in place. The RIAA board is attached with gommets for vibration isolation. Note the big Jensen/Angela copper foil in oil caps. They sound even better than they look.



The finished panel for the controls. I really like the way this part turned out.



I used the same cutout style for the rear panel holding the RCA jacks. I used Cardas jacks for all but the two extra inputs.