Just received my amp+ and compared it against my old amp of 2018 using a switcher.
Physically nearly unchanged, volume knob definitely more fluid/smooth to the turn and inline with the better build amps like monoprice liquid spark.
I'd say subjectively at similar listening levels that the amp+ seems to sound "faster and wider" with better dynamics (attack-decays) amongst other technical sound improvements like deeper bass and a less shouty midrange. I'm using IEMs of various sensitivities and heard no technical defects. It's the improvement I was looking for, thankfully arriving before I had to consider to spend more on the Topping A50s and above (I really liked the A50s but this amp sounds close to it while staying SE).
Hopefully someone can compare these amps using science machines so that we can perhaps better measure the difference that would cause all these improvements? I've started to see people on other sites measure SINADs at other data points than just 1khz... perhaps we can see differences there?
(forgive the picture showing 2 knobs at various clock positions, it doesn't represent the tested settings).
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John's claim of great sinad performance across the sweep.
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