Analogue systems

I have the Sampler-Delay for about 2 Weeks now. I purchased it only 
because of the external feedback loop. Its so cool. When you put a 
good analogue filter into the feedback loop you get really analogue 
delays. They are as good as my real analogue delays.

What else do you guys put in the feedback Loop? So far the doepfer 
Modules Morphing Filter and the SSM-Filter work very well. The 
doepfer Moog-Filter doesn't work too well, the input is too low, so 
its not possible to get very long feedbacks. I will test is also 
with  Wiard, Oakley and blacet filters, when its in the main studio.