ByPass Factory amp

[oQuockYo]

Hi

Does anyone in here know how to bypass the factory amp in 01 x5 so that you can use aftermarket headunits so power the speakers?

tia

[Brian-bmw]

Do you have the DSP system or the standard amp?

[oQuockYo]

Standard.... any ideas? please i can't figure it out. never installed aftermarket unit in BMW before.

[Brian-bmw]

Since you have the standard amp, the swap is a little easier. You could simply swap the radio module by removing the BMW radio and then connecting the aftermarket radio to the BMW's radio plug with a simple adapter. That would give you new features, but it would not improve the sound that much, because it would still be playing through the stock BMW amp.

If you replace the head unit, you could also choose to replace the amp in the trunk. This would give you more volume and cleaner quality sound. That would take some wire splicing to tap into the audio signals from the radio and then feed the amp's signals into the speaker runs. Plus, you would need to install some "passive crossovers" for the speakers, because the BMW amp has internal "active crossovers" that you would need to substitute. This and an aftermarket head unit would improve things a great deal, but you would also need new speakers to capitalize on the amp improvements...

[oQuockYo]

The thing I am tring to do is power my factory speakers with my aftermarket head unit. Instead of factory amp. Is there any way do do this with out rewiring the whole cars speaker wires?

thanks.

[Brian-bmw]

OK, for that, you will want to pull both the factory head unit and the factory amp. The trunk is the only place in which both the speaker wiring and the head unit wiring coexist. So, you would just splice the head unit wiring over to the speaker wiring and then the head unit would be directly powering the speakers. But, you would need to add some active passovers in the splices:

Your car has 10 speakers, and these are all direct runs from the speakers to the factory amp. In a normal aftermarket stereo installation, you typically see direct runs per channel, and then some kind of passive crossover at the speaker locations to separate the lows, mids, and highs. The factory system does not have any passive crossovers, so you would need to add them. These are the speaker locations and functions:

• 2 front door tweeters
• 2 front door midrange speakers
• 2 front door woofer speakers
• 2 back door tweeters
• 2 back door woofer speakers

So, to bypass both the factory head unit and the factory amp, you would need to add a three-way passive crossover for the front door speakers, and you would need to add a two-way passive crossover for the back door speakers. It is hard to buy an aftermarket crossover that is tuned to your existing speakers. So, it might be a lot easier to just buy new speakers that come with passive crossovers (like the Bavarian Soundwerks kits), and replace your speakers along with the new head unit.

[oQuockYo]

Wow sounds like a pain in the butt. But thanks alot Brian-BMW you are a gift to this forum that was very helpfull.

Thanks.

[Fly Guy]

This is what I need to do. But I'm a little unclear of the process