Hello , i am planning to install aftermarket dvdgps for BMW X5 2005 E53 3.0 dashboard. car has cd player and radio with DSP button so DSP amplifier in the trunk left wall. i just found on ebay the following link that someone is selling DSP sound adapter which is fully compitible with E39 AND E53 which car has already dsp. generally after market doesnt give sound with aftermarket multimedia but what they claim is it is possible with their small adapter just doing little wirings. so we can save money for aftermarket amplifier and speakers. and they says that it give s sound in all 12 premium boss speakers plus. this adapter converts analog signals from aftermarket multimeida to DIGITAL format and send to DSP amplifier and not only that it send low frequency signals under 4 volt which is generally more suitable for DSP factory amp.

Adapter for Acquisition of DSP Amplifiers at BMW Harman Kardon Nokia Top CA | eBay

price they are asking is 300 usd incl shipping...any opinion or any other suggestion please?

where chinese aftermakret multimedia mfg. suggested just to by pass DSP amplifier and connect 4 DOOR SPEAKERS directly without factory DSP AMP. SINCE MULTIMEDIA HAS ALREADY BUILT IN DSP amplifier so it will give better sound in 4 door speakers. BUT I AM WORRIED ABOUT TO LOOSE SOUND IN REST OF THE TWITTERS AND SUBWOOFERS.
PLS HELP
THANKS