New DISPRE preamp, successor to previous popular version

Hi PMA


Interesting circuit, i am currently building your first circuit after a friend of mine recommended it but am i bit confused on the operation. Is this vas a folded cascode ??
I have schematics of a amp (i think its russian) which uses the topology aparatusonitus shows. My buddy built it as well and says it sounds great, better than his stochino amp. What do you think of such a topology. I will post the schematic as soon as i find it again on my harddrive, but maybe on another thread not to hijack this one.

Alex
 
They lie below -140dB, which is both inaudible and unimportant. OLG vs CLG and transient response with same shape for any output voltage are very important.

You can make this pre without ANY global FB, by proper resistor choice and 1 added resistor. I have decided to make it this way, with slight feedback.
 
I would like to display what I mean a "consistent step response". The attached image shows step response for 10V and 1V output step, in one image, 1V response 10x magnified. This is WITHOUT input RC filter. As one can see, there is no slew rate limitation visible.
 

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PMA said:
I would like to display what I mean a "consistent step response". The attached image shows step response for 10V and 1V output step, in one image, 1V response 10x magnified. This is WITHOUT input RC filter. As one can see, there is no slew rate limitation visible.
Hi,
can you confirm that the plot shows about 0.2uS for a rise from 1.5V to 9.5V giving ~40V/uS (for that test signal) and still showing no sign of slew limiting.