What is the input impedance of the Classe DR-9 amp


The crossovers on my new Vandersteen Quatros have to be set up to match the driving amp's input impedance. Unfortunately, the owner's manual that came with my Classe DR-9 doesn't give the input impedance. Does anyone know the value?
tmatheson
According to a review in Stereophile vol 11 no 10 by Arnis Balgalvis, input impedance in stereo mode was 100k and in bridged mono 25k.
Thanks for the input. Tech support at Classe couldn't tell me for sure, saying they thought it probably was 50-100K, similar to the responses here. I might have to resort to finding an oscilloscope and 'tuning' the crossover based on how the amp responds to input waveforms.
The Model 15, similiar to the DR-9 is 70K into the RCA inputs. The balanced input is probably 1/2, not double as you would expect. This due to the fact that the circuit is not true differential. Either way, any pre-amp will drive it to full output no problem.
According to information I found on the Internet, the input impedance is 53,000 ohms.
I believe it is 100K ohms.I had these in a bi-amp situation with various crossovers.