Audio set Siedle Compact in 1+n technology with the functions of call, voice transmission, and door opener. Number of integrated call buttons: 4. Each Compact set can be expanded by one additional indoor station per call button and supplemented with a secondary signal device. Delivery includes: Siedle Compact audio door station (brushed stainless steel), 1 standard indoor telephone, and 3 transformers.

The features of the door station CA 812 include an integrated door speaker, adjustable voice volume, and a number of integrated call buttons: 1 (CA 812-1), 2 (CA 812-2), 4 (CA 812-4). The backlit nameplates are interchangeable from the front, and there is a backlit information sign for house numbers, logos, opening hours, etc. The device is designed for surface mounting with a brushed stainless steel frame.

The features of the indoor station HTS 811-0 include a door call as a 3-tone call and a floor call as a 2-tone call, which is possible in the Compact set with ZERT 811-0. Integrated call muting is available via the volume control, and the call volume can be continuously adjusted from the outside via the volume control up to a maximum of 83 dB(A).