We have very different experiences with NORDOST perceived “brightness”.
It’s important that varied personal experiences are laid out for the OP, so thx for posting yours .
I never had my NORDOST “brightness” described as a weak / underwhelming bass issue. Rather, their audio “bright” performance could still mine the bass down down to bedrock levels, but it also had an added emphasis/ result/ expression / (insert your own similar metaphor or description…) to make the sonic signature more noticeably “forward” and “cool” versus a “neutral” presentation in its classic sense, across the spectrum .
Introducing a CARDAS CLEAR cables full loom ( all of ICs, speaker , amd power ) provide me with that performance that aligns with the HARBETHs design and their legendary and class-leading midrange sonic signature, …. along with a further added presence, slam, and dynamics - that is not subtle- in MY system. ( emphasis added )