Beedub said:
ive mentioned this a few times, and i dont expect anyone to agree with me, but this is my 2p worth, i find the stock DSP system absolutely fantastic. My shop fits high end Audison / Hertz systems and let me tell you, it takes a beefy, expensive setup to sound as good as the carver system in my z4. It lacks some deep bass, but i really like it, my DSP was setup by audison for me.
It's not that hard to believe was it not a £2.5k to £3.5k add on 20 years ago?
The amp alone was funny money. I thought it was great stock OEM but the fact it lacked Bluetooth and other modern features, DAB radio, etc I opted to upgrade the head unit which meant an overhaul of everything bar the stock speakers.
Having a much better source providing the signal has made it even better and a clear difference. The only issue is the 4 woofers are extremely hard to drive. I can only use the vocal equaliser settings or they are too demanding for the amp to max out the volume. But on vocal I can do that and the bass literally rumbles through you even on that setting depending on the song choice.