OH -
Not necessarily though, and the fact that any amp is USB powered shouldn't matter much...
Its the output, the amp section, its power, damping, and how the circuit deals with separating the noise from the signal path.
You can actually, in many cases, get better bass response from open cans!
I know this may fly in the face of how you might see it now - and I TOTALLY GET THAT.
So I'm NOT shooting you down.
But put it this way - the fact that the MS even drives my Audeze LCD-3's to a dB level that feels realistic, not to mention the detail retrieval
and imaging, wow! Now - I'm not saying the MS is the perfect mate for the Audeze LCD-3 - but when I reviewed the MS
I HAD to point out that this lil brick could drive those phones well enough for me to take the MS and LCD-3's to Hawaii w/ me on vacation!!
I needed to show something - that no matter what powers an amp, USB, AC, it's how things are executed that matters.
And when it comes to bass. Ask my good friend and mod here
@warrenpchi - and others, you can often find bass just as deep, if not deeper
through open cans! And YES the Mad Dogs are closed! They were the first closed orthodynamic headphone I heard and loved, because it sounded closer
to my Audeze LCD-3! But they also gave my wife some peace and quiet (I write/work from home).
So all I'm saying is don't rush to generalize, like with USB powered DAC/amps.
The Light Harmonic GEEK puts out a clean watt and it BLEW US AWAY at RMAF!!
Driving my LCD-3's, playing Nirvana's "Come as You Are"!!
That MAY be the one that unseats the MS for me. It's the strongest contender!!
but for now I'm still blown away at the microStreamers sonic capabilities...