Assen Gereformeerde ZuiderkerkAssen Gereformeerde Zuiderkerk
1931: New pneumatic organ by Valckx & Van Kouteren in Rotterdam.
Specification:
| Manuaal I | C - g3 | Manuaal II | C - g3 | Pedaal | C - f1 |
| 1.Prestant | 16' | 12.Bourdon | 16' | 22.Subbas | 16' |
| 2.Prestant | 8' | 13.Vioolprestant | 8' | 23.Gedektbas | 16'* |
| 3.Bourdon | 8' | 14.Roerfluit | 8' | 24.Violonbas | 16'* |
| 4.Salicionaal | 8' | 15.Viola di Gamba | 8' | 25.Octaafbas | 8' |
| 5.Concertfluit | 8' | 16.Voix Celeste | 8' | 26.Cello | 8' |
| 6.Octaaf | 4' | 17.Open Fluit | 4' | 27.Bazuin | 16' |
| 7.Fluit | 4' | 18.Woudfluit | 2' | ||
| 8.Octaaf | 2' | 19.Sesquialter | 2-3-4st. | ||
| 9.Mixtuur | 3st. | 20.Basson Hobo | 8' | ||
| 10. Cornet | 3-4-5st. | 21.tremolo | |||
| 11. Trompet | 8' |
1962: Changes to the specification by Mense Ruiter of Zuidwolde.
Specification after the changes:
| Hoofdwerk | Bovenwerk | Pedaal | |||
| Prestant | 16' | Bourdon | 16' | Violon | 16' ** |
| Prestant | 8' | Prestant | 8' | Subbas | 16' |
| Bourdon | 8' | Roerfluit | 8' | Gedektbas | 16' ** |
| Octaaf | 4' | Viola di Gamba | 8' | Octaafbas | 8' |
| Fluit | 4' | Voix Celeste | 8' | Octaafbas | 4'* |
| Nasard | 2 2/3'* | Octaaf | 4'* | Octaafbas | 2'* |
| Octaaf | 2'* | Open fluit | 4' | Bazuin | 16' |
| Mixtuur | 3-5 st.* | Octaaf | 2'* | ||
| Cornet | 5 st. | Woudfluit | 2' | ||
| Trompet | 8* | Quint | 1 1/3'* | ||
| Sesquialter | 2 st. | ||||
| Scherp | 4 st.* | ||||
| Basson Hobo | 8' |