You can set your Bartók to 2V out. The 1.41V input sensitivity means a gain loss of about 3dB (-3.03622128226386dB, to be precise), so to be safe, you can set your Bartók’s volume level no higher than at -5dB, to prevent your amp from going into clipping. It will output 1.13V max.
To calculate yourself, for other voltages, you could use this:
Voltage and Gain