I kindo of keep up with the various exhaust posts, even since I installed my MBRP, just to see how the other systems are ranking. I've had several brands, but MBRP seems to fit what I like. Each time, however, I contemplate another brand, but I see drone mentioned alot.

Is this drone just something we have to deal with when buying an aftermarket exhaust? What causes it? Can it be eliminated with systems that have it?

Thanks,

Smoke

 

Hey Smoke.

Several factors.

Drivetrain architecture with attendent natural resonance frequencies. In the 5.4's case, usually 1800-2200 rpm.

Muffler shape/construction - ovals tend to cancel out wavefronts internally - while rounds tend to reinforce same. Wall thickness, packing type / baffle type (if any).

Muffler internal volume - notice the OEM is HUGE, lol. Smaller volume, more 'noise'.

Muffler location - quieter towards the back.

Hanger location / hanger type .... & on & on

It's complicated. An aftermarket install tends to upset all of the Geek's careful design work w.r.t NVH.

EDIT: oh, yeah, it's also Load-based, as that is when exhaust gas volume is at it's highest. Think pulling a looooong hill.


Darren will be along shortly with his posse of to flame me


MGD

 

I'd say drone is most often associated with interstate driving. Essentially, it's the amount of noise coming from the exhaust, and how loud it is inside the cab while driving. "Interior noise" so to speak. Muffler size and loudness will determine how much drone you have, usually. Muffler placement also has an effect, for example if the muffler is where the bed and cab meet, you will have much more drone than if it was near the end of the bed. That's what I've gathered anyways.

 

I think MGD hit it on the head.

 

Now, could someone please hit HIM on the head?

 

Wouldn't work - Canuckian, remember?

You'd need one of these:


MGD

 

Well you got the hammer Jim....

But I can def borrow it if you want

 

Help! ITG's! ITG's!

 

Pretty good MGD!
Don't worry I won't hit you on the head.
To cold up there in Canada!
It might shatter. Eh!

 

I don't think Darren's cronies are going to disagree with you MGD. My round bodies drone pretty hard. I know it, the exhaust section knows it, everyone that lives on the roads I drive on know it. IMO, the ends justify the means. I get hard (lol) when I'm in the 2000-2500 K range, but below that, it's a small annoyance.

 

Yes MGD you got it spot on. I'll also add cab and bed lengths play a small role in the sound inside, and so do the tip length and locations. True dual exhausts will vibrate more and make 60% more inside noise from the vibration and sound waves, especially without a cross over.

I was very surprised when you posted your first videos at how loud it was inside . You have a hell of alot more inside noise than I do.. For now.