I like simple stuff so I have made Ironhide IPS board. It is a CFA (current feedback amplifier) design with unique single ended voltage amplification stage (which is not so commonly used in CFA amplifiers) and j-FET input. DC servo keeps the output offset close to 0mV so there is no adjustment needed, just plug & play and job done. Very simple/single capacitor compensation provides good gain (PM=65dB) and phase (GM=28deg) margins. Loop gain starts to drop from about 10kHz @ 35dB to reach ULGF (unity loop gain frequency) at about 630kHz. The rest of the measurements coming soon.
Sound ? Nice and smooth top end, very neutral, so neutral that can turn out a bit boring at the end of the day but no headaches are guaranteed.