DIY Passive Preamp / Isolation Table


I started with some 3/4" MDF and made a frame.
Then over to the router table to cutout for the recessed top and bottom.


Next a first pass cut for the plexiglass insert.
Followed by a cut through with the table saw.


A perfect fit for the 1/4" plexiglass rod.
Now for the corners. Mark the 1" round stock and rip on the table saw.


Cut the corners of the frame to match and you get rounded corners.


I cut out the back for the recessed connector panel.
Then a lot of primer, sealer, sanding and painting.


I got this AR TDS module off Ebay for $10 and pulled the module out.


A 23 step attenuator with 1% Vishay-Dale resistors and TDS mounted.
I used a flex shaft out of an old Yamaha CR-640 for the billet control knob.
There is also a cold cathode blue neon light inside.


The internal wiring is shielded coax.
The lettering was done with rub on letters I picked up at a hobby store.


Finished with Krylon Semi-Flat black and several coats of DEFT
and all setting on Daruma Isolation Bearings.