One of the weak points of the Revox A700 decks is that the 7 slide pots used get noisy fairly easily. They are an ‘unobtanium’ type of slide pot, that mount to the chassis from the back of the control, making them unique. There is a company in Germany that makes replacement fader assemblies, however if the controls are intact and just need cleaning, we can do that via this tech article.
Material needed:
– Philips screwdriver to take off the front panel
– super small straight blade jeweller’s screwdriver
– can of DeOxIt spray
The manufacturer of the slide pots put a thin piece of mylar on either slide of the slider shaft, apparently to prevent dust and dirt from getting into the slider. 45+ years later though, that mylar seems to keep accumulated dust in the pot itself. Because there’s small groove that the mylar sits in, it’s nearly impossible to get the DeOxIt spray around it to get down into the fader itself. If you pry apart the plastic fader housing, the mylar piece will warp, and cause very uneven action on the fader, making it difficult to move.
So, what we’ve found is that you can actually remove the mylar covering, which now exposes the carbon fader at the bottom of the control so you can shoot some DeOxIt into each fader. While its possible for a bit more dust and dirt to get into the fader, the DeOxIt leaves a residue behind, to keep cleaning the fader as you use it.
View under the top cover of the A700 audio section. The picture above shows the left 3 faders with the mylar removed, the far right fader still has it in place.
Take a thin straight blade jeweller’s screwdriver to gently pry the mylar film from one edge of the fader. Once one side is loose, you can pull on it, and it will come out of the small track that it sits in.
Prying the mylar film away from the edge of the fader.
Once you have one edge of the mylar loose, pull on it, and it will come right out of the fader in one complete strip.
Once the mylar strip is removed from the fader, shoot a small squirt of DeOxIt into the control, and work the control up and down a few times. With the 2 decks we’ve done this procedure on, the DeOxIt actually helped lubricate the fader, and the slide action on all of the ones we’ve worked on was nice and smooth. No DeOxIt Fader Lube needed.