this is my experience regarding the issue but before that i am not an audiophile but i love to listen to music, this is my opinion only im sure others will disagree
i spent quite abit buying audio and came to the conclusion its mainly ur speakers/headphones that determine sq and sound signature. an amplifier's job is only to amplify the analog signal to listening levels without distortion. the called "sound of amp" is just coloring of the frequencies to the final analog signal. i think this is why people may call it synergy.. say u have akg701's which lack bass, obv an amplifier that colors the bottom end would be a good "synergy"
i recently sold my essence stx for an audio gd fun, i couldnt hear too much audible difference between the dacs both were very clean and clear to me. maybe if i a/b a song i knew very well. so after spending alot more on an dac/amp i couldnt justify any tangible differences..
however now ive come to realise what i paid for is not the sq but the ability to change op amps (color the sound), the preamp/amp function, the build quality/looks and the mobility over the stx.
so at the end of the day your akg 702 will def be driven to what its meant to sound like but i dont think it will sound "better" just what its meant to sound like with minimal distortion and enuff power for listening levels but you have to justify the 800 spent if it was worth what you purchased
me personally i would rather spend it on a cheaper amp and even get another pair of headphones for a diff sound signature
lol at this rambling (hope it helps) but this is what i came into realisation about purchasing amps lately and made me realise how much value i got out of a 300 audio gd fun :D
