Klangfilm EQ

These units all required extensive repairs, but the sound is amazing. Some of these are RZ062 with an EF804s / ECC81 amp and some are RZ057 which have 2 EF804s. These units use polystyrene caps, resistors and inductors for the EQ circuits. They are from a couple different Telefunken consoles.

These resistors are just one problem with these units. You can see the split cap on the upper one. There were a lot of these which required replacement. Some of the units would squeal with oscillation and the troubleshooting was not trivial.

These are some of the most complex units I have worked on. Troubleshooting them required grokking the circuits and understanding the complex switching. Click here for the manual.