These preamps are of very nice quality. In a standard cinema setup there were
  - 4 KLV 004
  - 1 KLV 006
  - 1 KLV 007
  - 1 KLV 009
installed in one mounting unit (Einschubträger). In most instances there were two rows of these amps (with a total of 14 preamp units) and in the second row you found a KLV 008 microphone preamp.

  The magnetic sound preamp V-004 with 1 EF804s and 1 EF40 and the record player preamp V-009, which uses 1 ECC83 tube, look different, but the circuits show similarities.u can keep

Model

KLV 004

EF804s

EF40

  T54 input transformer and T55/3.5 output transformer!

KLV 006

  T55/2 output transformer!

KLV 007

ECC83

  T55/2 output transformer!

KLV 009

  T41 input transformer and T55/2 output transformer!