So I just installed a NXT step exhaust yesterday and all is well except I noticed that it begins to drone at 1500-1700rpm, past that it sounds basically perfect in terms of volume and sound. Now I am no prude when it comes to exhaust sound, but this particular drone seems to agitate me to the point where my ears hurt after a ride.

To the exhaust's defense my car has always had a bit of a rumble at around 1500rpm and considering the fact that an aftermarket exhaust basically just amplifies these characteristics I am not surprised that I am hearing this.

But the drone has been so noticeable to me that I've been driving around thinking that I have this super low pitched motor boat sounding exhaust. Yet today I took the targa top off and the exhaust sounded exactly like I thought it would, a slightly louder throatier version of the stock exhaust. What was the most interesting thing to me though is the fact that I really didn't hear any of the drone or deep rumbles with the targa top off. Yet I did the same trip later today with the top on and the car seemed to drone as it has done on all of my previous rides.

So my question is: Could there be something specific with how the targa top transmits harmonics/vibrations that could be causing my car to sound more droney?

I guess the other question that I have is how exactly would I go about reducing/eliminating this drone?

 

I'd guess the drone is still there but is drowned out by the added noise from having the top off.

 

To eliminate the drone, try an x-pipe on the car. It worked for me when I had a set of B&B Route 66 catbacks on my car and they had a terrible drone. And yes, the fact it is louder with the targa top on the car is very plausible.

 

Yeah I just did another ride with the targa top down. The exhaust's drone was definitely still there I guess I just did not feel as many vibrations throughout the car.

Well I think I will try adding some insulation/sound deadener to the rear of the car since that can be done on the cheap. I'll also give the exhaust a few more miles to "break in". If that doesn't help we'll try the X-pipe.

The good news is that on the highway I'm usually at around 2000RPM, which sounds basically quiet with this exhaust. When I'm at 1500RPM in the city, I could probably drive closer to 1200RPM which is much quieter (and more fuel efficient)

What's interesting is that I really don't blame the exhaust. I just think the way these cars are built they are going to have a low droning sound at around 1500rpm. My car definitely had that sound with the stock exhaust, it just wasn't as pronounced since it was quieter.

 

I'd have to disagree with you. Yes, there is more noise in these cars because they're basically plastic with a steel frame and aluminum/balsawood floors. However, you can have a much louder catback exhaust with no drone whatsoever. Corsa for example, is known for eliminating drone/ resonance in their catback systems. Some other catbacks are known to exhibit severe drone. It's all in the design.

 

I just put B&B bullets on mine and have a lot of drone. I expected some but it's pretty bad. I may have to try the X pipe. Made a nice difference?

 

Some of the drone will fade after you put more miles on the car

 

When GM was looking for an aggressive exhaust for the C5 Indy pace car, several manufacturers offered a custom exhaust. IN talking to Corsa design engineers I found that sound can be bent by design but you can not get great idle, great wide open throttle with no drone at cruise.. you can only get two out of three.. because the harmonics of exhaust pulses will not allow the frequency responses to cover all three, each has to be tweaked with chambering.. its a science.. so to get no drone at cruise, you have to sacrifice either WOT, or idle.. Corsa have absolutely no drone. Its important at that critical cruise range of 1400 to 1800 rpm..
Many manufacturers go for the obnoxious idle.. many customers want their car to sound this way at idle.. but they have to pay for it at cruise, with drone.
Some people find that adding an Xpipe helps, but because of the specific design of individual exhaust systems, there is no guarantee.

Some people buy an Xpipe and psychologically makes it seem better. If an Xpipe helps, its only by luck. I wont add any further input into this thread...this is just from my conversation with Corsa engineers..
BTW as many know Corsa Indy Pace car system has a GM part number and makes that exhaust considered stock. Not trying to push the OP toward a Corsa system, just trying to explain why some exhaust systems drone.. I would hate to see the OP buy an Xpipe, waste that money and not correct the problem.. This is the reason that I always say. I can not afford to buy anything too cheap... Corsa exhausts are expensive, there is a reason for that.. extensive research, quality control, and the end product.. that's why they are so popular.
I know plenty of people that will buy a 300 dollar exhaust system that sounds " cherry Bomb " obnoxious with obnoxious drone , and they love it.. e.g. the ricer fart can exhaust that many kids put on their car. to me that noise screams cheap, its certainly not muscle car or exotic...

 

Drone is a harmonic frequency response, the only way it will fade is if the mufflers change. The only way the sound will fade is because your ears become use to it...
e.g. live near a rail road track, when you first move in, you can hear the trains. After a while, you never notice them , but they are still there..
Meaning, some people will get use to it, other wont. Also, if you do extended highway driving in that cruise range every day, you are not going to enjoy your commute.. many members over the years have talked about headaches after 30 minutes on the highway. If you are not doing a lot of highway driving and you enjoy a better idle tone then , there should not be a problem. If you spend most of your time in 1st, 2nd, and third gear, you bypass that drone range quickly. If most of your driving is in 4th , 5th, and sixth, drone could be a problem.

 

I have the Corsa Sport exhaust on mine with the OEM H-pipe. No drone.

 

Corsa Indy Pace Car edition

Installed in 2001 on my 98 along with the Corsa X-pipe and 13 years of happy drone free cruising, targa on or off.

It will bark loud when instructed.

 

the topic says, quick drone question.. unfortunately... there is no quick answer.. as evidenced by my less than short and quick answer.

 

This is incorrect. Neither Corsa systems nor GHL Bullets have any drone whatsoever. It's all in the design of the exhaust, not the design of the car. My GHL Bullets have zero drone at any rpm. Corsa exhausts are the same.

 

Does anyone know if the Corsa Extreme has any drone??? I can't take the drone of my B&B Bullets after only a week. They have got to go. I want loud without drone... Is that too much to ask??? LOL

 

unfortunately.. many people who own B&B Bullets claim they do not drone.. but because of their design they do in fact drone, they are designed for a robust idle , which makes them drone at cruise. Your Bullets are acting like bullets.. some people with bullets do not know what drone actual is.. I've heard people say it sounds cool.. much like the obnoxious base tone you see kids who want attention in their car with their speakers blasting that horrible base tone drone that rattles your windows two cars away...

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Heck, if drone is a problem buy a bigger sub woofer, if weight is a problem get a bigger cam. Want to sound bad ***, buy Borla Stingers.

 

I appreciate all of the responses and insight. I do think drone is a very pervasive topic when it comes to exhausts, of course some people go "oh this exhaust has zero drone" when it really does, and others will say the inverse. What's just funny to me is that in all of the aftermarket exhausts I've purchased I had never really experienced drone before.

I don't necessarily mind the deep rumbling sound that the exhaust makes, but it's really the vibrations that seem to bother me.

Hopefully some more miles on the exhaust and some insulation will change things for the better.

 

I started out with a completely stock C5 Z06, I then added LG long tube headers with an x pipe and the stock Ti exhaust, while It did sound pretty good to me it was to raspy at WOT, which I did not care for...so after listening to a few other vette's at event's and most having a either borla or B&B bullets, which sound great don't get me wrong but they DID drone, I went for several ride's and even the owner of the car was not happy with the setup...So knowing that before I bought I ended up with a Corsa Indy Pace cat back, and with the LG headers it's sounds amazing, and there is ZERO drone, its loud when I want it to be, and cruising down the hwy at 65 mph I can have my stereo on 10 ( I just have double d mods touch screen unit with stock speakers) and my radio drowns out my exhaust...like EVIL-TWIN has said, the Corsa's really do NOT drone...


a side note of those people who have ridden in my car, I know a few have switched to corsa's since then. and they could not be happier..

 

Corsa systems and GHL Bullets actually do have zero drone. They're the only two systems well known for not having any.

 

I have a Corsa Extreme catback with XO pipe. I can attest to the fact that there is zero drone. Nothing at all!!! The exhaust is loud when I want it to be (WOT) and nearly quiet at highway cruising speed. I am completely satisfied with it.