I had access to the radio quadlock connector today and measured MY07 stock door card bass units. Mine is the basic V.W system 2 bass units low down at the bottom of each front door card, 2 bass units either side of the rear bench seat and 4 high level hf tweeters. There are no mid range units fitted in the door cards and I might add a pair of front mids with an active or passive crossover.
I haven't measured the tweeters yet, that's for the next time I have the door card off. These are my actual bass unit measurements for anybody wanting to make changes, add a sub or design a crossover for multiple speakers. The spread of resonant frequency is about what I would expect, given their size and age averaging at 66Hz. The impedance of each bass unit measured at 1kHz was 8 ohms. A crossover cutoff (-3dB) is generally accepted as 4X the speaker resonant frequency, i.e 265 Hz
Results:
Rear left: 69Hz
Rear right 66Hz
Front left 62 hz
Front right 66Hz.
I haven't measured the tweeters yet, that's for the next time I have the door card off. These are my actual bass unit measurements for anybody wanting to make changes, add a sub or design a crossover for multiple speakers. The spread of resonant frequency is about what I would expect, given their size and age averaging at 66Hz. The impedance of each bass unit measured at 1kHz was 8 ohms. A crossover cutoff (-3dB) is generally accepted as 4X the speaker resonant frequency, i.e 265 Hz
Results:
Rear left: 69Hz
Rear right 66Hz
Front left 62 hz
Front right 66Hz.