Originally Posted by Jch99
You have a M3 also? or are you saying the bass in your 335 no longer hits as hard as before?
I have an E90 M3, but had a E92 335i before with an L7. I couldn't find an M3 with the HK L7 system, despite my efforts
the main difference is that the HK L7 sounds more full and alive at low to moderate levels. The L7 "subs" definitely move more air as well, evidence by the rattles from the sideskirt area when you turn up the music.
The Enhance System lacks thumping bass at low to mid volumes, and if you turn up the 100hz or Bass adjustment's, it seems like the bass rolls off after 70-80hz, while putting way to much emphasis in the 250-500hz region, sounding IMHO quite harsh. It does sound quite good when played at high volume levels though, with "full" bass response, good midrange power, but a bit peaky with the higher notes. The L7 seems to get muddy and too bass heavy the louder the volume.
On a side note, I've heard the Hi-Fi system on loaner cars I've had in the past, I feel it has a "warmer" sound quality at low to mid volumes as well.