Spreeman Piano Innovations makes Ravenscroft pianos. There are two models, a 220cm one and a 275cm one. It turns out that these pianos contain a lot of Sauter DNA. The Ravenscroft Model 220 is the equivalent of the Sauter Omega 220, and the Ravenscroft Model 275 is the equivalent of the Sauter Concert 275.
Sauter supplies the the finished rim assembly with the keybed, lyre legs, pedal work and all hardware. They also supply the action, hammers and keyboard, the finished plate and the raw Ciresa soundboard sheet. Spreeman does all work on the soundboard, produces the bridges, ribs etc. The Ravenscroft action geometry is different and there are slight string scale changes.
Ulrich Sauter says that there are some minor differences in terms of voice (and touch), especially since the soundboard has a Steinway “belly rail”, which Sauter does not have (nor believe in). But all in all the general Sauter “sound character” is still there. He goes on to say that this proves that the string scale is mainly responsible for the sound of a piano.