I have just put an upgraded subwoofer into my S7, in effect replacing the Bose woofer which is underwhelming for what is supposed to be a premium sound system.
I looked at a number of options, including replacing the the Bose speaker within the OEM enclosure and adding a separate amplifier just for the subwoofer.
I removed the bass enclosure and visited my local car audi dealer for advice.
After he picked himself up off the floor, crying with laughter and asking how anyone can seriously consider a thin plastic subwoofer to be a premium product, he removed the Bose sub from the enclosure and compared it to one of his stock subs. The difference was night and day, and the cheap parts used in the Bose construction was clear to see (made in China, say no more...)
After further discussion we agreed replacing the sub into the stock Bose enclosure would not reap any benefits, and may actually worsen the situation due to the cheap material used in the enclosure construction we agreed on a separate quality subwoofer and enclosure, that included an integrated amplifier.
I don't use the S7 to haul stuff around, so the boot area is normally pretty clean and empty, but as I didn't want a huge sub enclosure taking over the boot, settled on a compact 8" quality sub and box with integrated amp.
I did the install myself - it was very simple. Power and speaker level input (from the original Bose speaker) Took about an hour all in.
The overall sound of the system has significantly improved, and Im very happy with the results.
I could have spent a shedload of money on stripping out speakers and installing crossovers and multiple amps. Instead I spent under £500 and have a radically improved system that Im now much happier with
Pics of the original Bose speaker and enclosure and the new Sub below.
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