Bass roll off fitting in car measurement

[KrisJLee]

HU is a Pioneer DEH-80PRS running 3 way active with time alignment and 16 band EQ

Rockford Fosgate Punch 100ix running tweeters
Rockford Fosgate Punch 4040 DSM bridged mids
Rockford Fosgate Punch 40i DSM bridged running sub

Speakers
Audison Voce tweeters in custom pillars
Audison Voce 6.5” mids on aluminium baffles bolted to the solid and sealed inner door skins
Rockford Fosgate Audiophile RFA810 10 inch sub running IB on a 72mm baffle under the rear deck

I’m measuring with a RadioShack SPL meter at the drivers headrest with a phono to headphone adaptor into my laptop and I’m running a calibration file on the meter.

I’ve downloaded the full range Periodic Pink noise as a WAV File and I’m playing it via my phone into the HU via USB input

The response curve looks ok after a bit of EQing but the bass roll off is crazy and it can’t be true as if anything the bass is on the heavy side.

Is there something obvious that I’m missing?

 

[John Mulcahy]

Looks like there is a high pass crossover filter being applied to the input.

 

[KrisJLee]

Looks like there is a high pass crossover filter being applied to the input.

Yes I’d agree. Looks like 200hz but the car is playing full range and I think the final is too. I’ll try with a pink nose CD and see if it’s the same. If so then it must be a soundboard issue

 

[John Mulcahy]

Is the mic input stereo? Windows tends to apply noise cancellation by default on stereo mic inputs, that rolls off the low end. It can be fixed by ticking the box to disable all enhancements on the Advanced tab of the Windows audio properties for the input.

 

[KrisJLee]

Is the mic input stereo? Windows tends to apply noise cancellation by default on stereo mic inputs, that rolls off the low end. It can be fixed by ticking the box to disable all enhancements on the Advanced tab of the Windows audio properties for the input.

I’ll check that john

 

[KrisJLee]

Is the mic input stereo? Windows tends to apply noise cancellation by default on stereo mic inputs, that rolls off the low end. It can be fixed by ticking the box to disable all enhancements on the Advanced tab of the Windows audio properties for the input.

Looks like you hit the nail on the head. This is my Apple HomePod mini before and after the setting change, orange bring the new setting and showing an extended bass response