Re: Upgrade my E39 DSP sound system-Atn. Bob Hazel (archive)

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The best "guaranteed" improvement for the DSP system is a subwoofer and sub amp upgrade. A speaker upgrade is risky because it is not possible to undo the digital electronic crossover which is matched to the Nokias. It is doubtful that even much better speakers will end up sounding better since the BMW crossover will be very unlikely to match them well. It's possible it could work, but it may require quite a bit of experimenting.
I'd suggest adding an amplifier and a real subwoofer, and see if you think further improvement is necessary. There are a number of good options. My ex employer, a/d/s/ makes some excellent products. I'd recommend a P2110 power amp driving a 310rs 10" subwoofer. If you don't have a local a/d/s/ dealer, any quality brand will have suitable equivalents. Look for Willard Lee's "installed a subwoofer this weekend" post below.
With the DSP system, you'll need to take the output after the factory amp, which is not ideal but for subwoofer use is probably not worth going in the box and tapping into a preamp signal.
If you're not happy after this, the next step is to upgrade the front speaker amplification. For this you will want a 6-channel amp, such as the a/d/s/ P640. With this step, I would recommend keeping the factory mids and tweeters because of crossover matching, but upgrade the 5-1/4" midbass drivers. I use the woofers from the a/d/s/ 335is system in my E34. The reason this will work OK is that with the new amp, you can compensate for the lower efficiency of the new midbass speakers using the amplifier gain controls. The factory amp does not have this capability, and pretty much any aftermarket speaker you are likely to be able to put in here will be less efficient than the Nokias. However, this lower efficiency will be offset by greater output and bass capability out of the new speakers. I would strongly suggest using a 6-channel amp in lieu of three 2-channel ones to avoid the noise problems common with multiple amp systems. As the final step, add another four-channel amp to the rear system, keeping the factory speakers. With the a/d/s/ amps you can connect the amplifiers to the factory amp using the connection described in the owner's manual for floating ground high power amps without needing to add line-output adapters. You should consult with your dealer regarding other brands, they may require these adapters. Optimally, a technician could install line outputs to the DSP amp by tapping into the signal at the input pin to each of the BMW syatem's internal amplifier IC's, but even without this, a good signal is available from the main outputs when these outputs are not driving a speaker load directly.

Best regards,
Bob Hazelwood
Product Manager, Cambridge SoundWorks
'93 525i 5-sp. Sharked, BL/ss'd, H&R + Bilsteins
BMW CCA (Boston)

: OK, I like the sound of my "premium" system, but I still feel the speakers and specially the subwoofer lacks quality and power. I noticed the speakers read NOKIA, perhaps changing to ADS or Boston Pros will make a huge diff from day one.

: Anyway, I know there are several posts on this issue, (how to, etc) but I have not seen a good LIST of thing to buy and the est. price for each component (and model#, etc)

: I dont want to spend too much on this upgrade (I think I already did it so), maybe the stock amp will be good enough. But definately looking for noticeable improvement on both sp. quality, power, and sub at least. I like rock music and top 40s at moderate volume levels. Maybe once in a while I'd like to crank it up, but surely w/o compromising quality.s

: My E36 325 had Alpine CD, 6 Boston Pros sp, Alpine 150x4 amp, and no sub. Great sound.

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