A further update on my 'minor upgrade'..
Time has gone by and I consider the speakers run in.advice being that 20-50 hours are required before premium speakers sound their best..
I used the Audiotec Fischer DSP configuration tool to re-adjust the sound setup using the Match 7 BMW specific AMP/DSP driving the Eton door, centre and rear speakers along with a pair Rockford Fosgate Punch woofers in the floorwells, along with an Alpine 300w RMS class D amp to drive the Audison BMW subwoofer replacements..over 1kw RMS of power available...good job the 210 amp alternator is fitted..
A review of the Match 7 is here.. https://www.audioexclusiv.ch/fileadmin/ ... Cr_BMW.pdf
I felt, at the time, slightly underwhelmed with the results relative to the expenditure and effort..
However, I did an interim tweak with the DSP s/w and it got better.
I then did bypass the BMW Active Sound Design box fitted to most if not all N20 powered E89s, which injects synthetic engine sounds into the speakers whether you want them or not and irrespective of volume.. see viewtopic.php?f=23&t=119642&hilit=ASD
This resulted in a further improvement as well as getting rid of by now a grossly annoying set of engine sounds..
The ASD interferes with the audio signals as they route through their on the way to the amps/speakers adding distortion and noise (in more than one sense)..
The Tecnics PNP bypass cable got round that problem (there is a much cheaper cable now available from Audison)..
So, COVID lock down, running out of things to do, I've spent two days revisiting the DSP programming..
The net result..a very impressive improvement in perceived quality..
How? Sadly by RTFM..there is so much functionality in these modern DSP amps..and given that there isn't a reference set up for the E89 its down to working steadily and methodically through and then going back an iteratiing..
The point is that with 8 channels and 8 speaker groups there is a lot that needs to be done..
The low pass and high pass roll off needs to be set to avoid speaker resonances for each speaker set and any uncessaary drive into freqeuncy ranges that the speakers are not designed for..eg on the sub-woofer..no point trying to drive frequencies much above 100Hz.
The sampling mike needs setting up with the appropriate 'reference curve'..that is..the frequency response curve best suited to a human in a small car, not in a large living room as an example listening to a hi-fi.
Each speaker needs to be set up for the time delay by measuring speaker to listener distance and entering that..
Each pair of speakers needs sampled with pink noise and then an equaliser correction factor applied to negate speaker and environmental aberations / factors..
Further adjusment of the time delay is then hand done to ensure correct spatial imaging between L/R and Front/Back for speech type imaging..
Each of these things needs to be done for each speaker set whilst disabling the others..
Trying to do this with a laptop /manual in the cockpit, doors closed, windows up, roof down (my preferred listening mode) is time consuming and potentially error prone..
However, after a night spent reading up and loading all the data from speakers etc I then did a 2 hour clean set up today and the results are now very impressive..
I guess my point is..given how unique E89s are in audio shops..how much skill/patience/time/experience does the average installer have/expend to get these things right?
Anyway food for thought..