"JW" wrote ...
I'm trying to find out if there is a way to connect the REC/Phones
output of my Roland Micro Cube amplifier to a Microphone input
on a laptop. Assuming the Mic-In is low impedance, is there a way
to convert the high voltage line signal of the amp to the microphone
input?

You need a simple attenuator to knock the line~level from your
amplifier down to mic-level for your laptop. Note that most
laptop mic inputs are mono. Hope you weren't expecting to
listen/record stereo. Impedance is really not the issue here.

All I found so far is to do the opposite: connecting a mic to
a line input.

That would be a mic preamp.

Where can I buy such a impedance matcher?

Last time I checked, you could buy a cable at Radio Shack
here in the US that had an attenuator built-in for connecting
line-level sources to mic-level inputs. Dunno if you have
an equivalent electronics mass-marketer in .nl? Likely
available someplace online also.

Or if you are a friend are handy with a soldering iron, it is
easily made with a couple of resistors that cost only a few
pennies. Information (more than you will ever need!) is
availble at www.epanorama.net

Also, I would like to know if it is ok to connect a 600 Ohm
mic to a 10kOhm mic input.

Yes. Impedance isn't really the issue here either.