“Driver Excursion” punch and slam are imo related to dynamics
Thinking of music as simply organized kinetic energy, poor dynamics indicate to me the driver’s inability to change from that lower output to a HIGHER, OR Higher to Lower output state FAST enough to sound real
There’s also the sensation of that kinetic energy against our skin.ears ect… so if a driver cannot accommodate that sudden SHIFT from one point to another FAST enough it will often lack a realistic dynamic range AND might also come across as sounding “soft” of lacking tactility or literally enough kinetic force to be felt,
Tho there’s also the matter of High to Low and Low to High, a realistic shift from Low to High will create that PUNCH or tactility, and some drivers do Low to High realistically and some are exaggerated, but they still sound Punchy
Then there is High to Low, being too fast High to Low makes things sound fake… ideally I’d like both PUNCH and tactility from that realistic Low to High and a realistic High to Low
I feel like on the right system 009 has amazing tactility but it “settles” from a high energy state to a lower one a bit too fast sometimes, HD 800 on the other hand seems more able to accommodate both the SUDDEN shift from high to low and low to high states of output in a manner that is more realistic but it sometimes doesn’t QUITE have that SLAM or weight I’m wanting
That said I feel 009 has more SLAM because it adjust to those low to HIGH shifts faster and often times it’s too fast because it’s settle from that High state into a lower one well too quickly,
Now imo some of the PUNCHY hifiman headphones are like the 009, tooo fast, my HE 4 was VERY much too zippy and fast. Sounded really cool but often fake, if Model 1 doesn’t have a TON of punch but sounds realistic enough low to High and nails the High to Low
It should do classical well, tho classical really demands perfection all around. There’s so much translated thru both the frequency and time domains, HD 800 does better for most of the classical I enjoy tho 2/5 times there’s a track where 009 does better