[AudiA4]

...my car has had MPE since day one of ownership, so I'm unsure if the "drone" sound under slight throttle/load is the MPE or Active Sound. In other words, does "Sport" mode modify my MPE in any way? I suspect what I'm hearing is the Active Sound changing output. Does anyone know?

[RPM1123]

Originally Posted by AudiA4

...my car has had MPE since day one of ownership, so I'm unsure if the "drone" sound under slight throttle/load is the MPE or Active Sound. In other words, does "Sport" mode modify my MPE in any way? I suspect what I'm hearing is the Active Sound changing output. Does anyone know?

Active sound happens in Sport Mode / Sport+. I was always suspicious of its existence as it is somewhat subtle, but a really easy way to tell the difference is do cruise control up a hill so the car has to rev up a little to maintain speed and switch between Sport/Comfort. It will be really obvious there's a little bit of exhaust frequencies being pumped into the cabin and are toggled on/off between those two modes.

[AudiA4]

Originally Posted by RPM1123

Active sound happens in Sport Mode / Sport+. I was always suspicious of its existence as it is somewhat subtle, but a really easy way to tell the difference is do cruise control up a hill so the car has to rev up a little to maintain speed and switch between Sport/Comfort. It will be really obvious there's a little bit of exhaust frequencies being pumped into the cabin and are toggled on/off between those two modes.

That was my assumption. So essentially, any and all acoustic value of MPE is strictly heard from the exterior...short of what "might" be heard in the interior, courtesy of the exterior exhaust note (which in my opinion, the MPE is very subtle).

[Blubaron79]

Originally Posted by AudiA4

That was my assumption. So essentially, any and all acoustic value of MPE is strictly heard from the exterior...short of what "might" be heard in the interior, courtesy of the exterior exhaust note (which in my opinion, the MPE is very subtle).

Fold your rear seats down. You'll hear all kinds of great sound.

[613Bimmer]

Originally Posted by Blubaron79

Fold your rear seats down. You'll hear all kinds of great sound.

Will try this tomorrow morning .

On another note, I have noticed that the drone does come from, at least in my experience, a mixture of the left exhaust valve opening in the MPE and the active sound amping up at the same time under increased partial throttle.

[eluded]

My car had a drone and when I disabled active sound… It when away

[spuntyb]

I have a bit of a drone but only in Sport+. We've been over this a million times, and I know they should be the same sound, but they're definitely different from inside the cabin and out on my car. Became even more pronounced after slapping on the AA piggyback tune, so I'm assuming it's all from the exhaust itself, and not ASD. Unless ASD is robust enough to detect the boost difference and thereby alter the sound, but I doubt it.

[raqautle]

I have a 435i and when coding it, I never saw the ASD which means I don't have it. Although it's a trend we noticed and can't really confirm officially, it appears that for, at least, the 2014 models N55 doesn't have ASD but N20 does.

[Versipellis]

Originally Posted by raqautle

I have a 435i and when coding it, I never saw the ASD which means I don't have it. Although it's a trend we noticed and can't really confirm officially, it appears that for, at least, the 2014 models N55 doesn't have ASD but N20 does.

Probably to compensate for the loss of two pots.

[fscuderia23]

i thought our cars didnt have ASD?
but anyways i second that the drone is caused by the flap. If you put the engine under some load in a higher gear at a lower RPM and accelerate up the rev range, you'll hear the exhaust suddenly wake up around 2k rpm (when the flap opens), but below it, the drone disappears

[AudiA4]

Originally Posted by fscuderia23

i thought our cars didnt have ASD?
but anyways i second that the drone is caused by the flap. If you put the engine under some load in a higher gear at a lower RPM and accelerate up the rev range, you'll hear the exhaust suddenly wake up around 2k rpm (when the flap opens), but below it, the drone disappears

Got it. For some reason, I thought the 335/340 also had ASD.

[chuckles01]

Originally Posted by RPM1123

Active sound happens in Sport Mode / Sport+. I was always suspicious of its existence as it is somewhat subtle, but a really easy way to tell the difference is do cruise control up a hill so the car has to rev up a little to maintain speed and switch between Sport/Comfort. It will be really obvious there's a little bit of exhaust frequencies being pumped into the cabin and are toggled on/off between those two modes.

I believe active sound is present on all modes. It's just louder in sport and sport+ modes. I had mine coded off recently and now the engine sounds so much quieter in all driving modes. I have a '14 328i though, so not sure if it's different with the 335i.

Also, I used to notice droning if I was cruising at around 80, especially obvious when my revs were around 3k on the highway (6 speed manual, so revs in top gear on the highway are higher than an 8AT). After coding the active sound off, the drone is pretty much gone.