Resonator placement

[BobbyB]

Put a cross over or X pipe in it. It will sound AND run better!

How much better than an h-pipe?

[Warp Speed]

X is typically a little better through the midrange compared to the H. Both typically need to be fairly close to the collector when using headers. Especially the X.
A properly placed X sounds way better too!

[Qtrhrse23]

What size Flows. Must be some 2 or 1 chambers. Have 3 chambers on a 92 GT with long tubes and Dr Gas X, sounds stock until I floor it(except for the D1). I agree Dynomax especially Super Turbos are nice and quiet. Hp might be a wash.

[Tuner]

A pal has a BBCwith a 6-71 in a '66 Nova. With 3" flomaggots and tail pipes exit out the side it had unbearable drone and was obnoxiously loud, 100+dB. He fabbed 3" pipes behind the flomasters and through the 4 link and over the Dana 60 to one of these under the trunk/fuel cell located with the two 3" exits under the license plate. Now all you hear riding in the car is the valve lash and the blower belt and it sounds so good it gets compliments from people who would usually ignore a car like this.
https://www.dynomax.com/mufflers/ultra- ... x-mufflers

[RCJ]

That's the muffler I have on my farm truck,everybody complements me on how good it sounds. My c6 corvette had an annoying drone when I got it. I tuned it up , aired the tires up, took some down force out of it. 50% of the drone when away

[malibuguy79]

Tailpipes will make the most difference, next is type of muffler. Next would be exhaust hanger style and motor mount type.

[Rick!]

Sound bouncing off the ground from single wall exhaust pipes back up into the floor, rear of cab, and front of box can also be excited by the reflected sound to cause "drone." Even large glass windshields can get excited by pressure pulsations (exhaust) or structural vibrations (uninsulated exhaust hangers) and turn vibrations back into pressure pulsations, hence noise. Turnouts pointed down are one of the most efficient ways to create unwanted interior noise in a car/truck. Even poorly designed mufflers can have their shell go into resonance, otherwise known as shell noise. It's usually at a higher frequency (4th to 6th order firing frequency) than typical exhaust noise frequencies
If you want to get all technical, download a free sound analyzer to your phone. Turn it on and drive in the drone speed/rpm and note the frequency. It'll probably be first or second order firing frequency (RPM x 8 )/60.
Maybe have a couple "muffler eliminator" tubes made and installed to see if the drone goes away. If the drone goes away, use some of the muffler suggestions above. If not, hang the system with the rubber donuts found on every late model vehicle. Drone still there? Tailpipes could be in your future.
RCJ brings up an interesting point - from a 10,000ft view, he basically changed the distance between the floorpan and the road if I'm interpreting the tire air pressure and downforce changes correctly. My old 76 Blazer with cam, headers, mufflers and typical tailpipes in front of the axle didn't have any drone - possibly due to the distance between the road and the floorpan. Something to think about.

[c1500sbc]

Thank y’all for all the input. I went ahead and just took it to an exhaust shop I’ve used a few times. They do good work at a good price. It’s no mandrel bent exhaust but it turned out great. I trust the guy and let him make some recommendations. He suggested the same as y’all. Dyno max turbo mufflers with an x pipe and I chose to exit with some dual tips straight out the back. Very similar set up to a 95 Sierra I have. I absolutely love it. Very mellow sound and no drone at all. Thanks again!

[F-BIRD'88]

My 3rd Gen Firebird was much like this except both tail pipes exited side by side, on the drivers side, at the back.
Makes the exhaust sound "mono" instead of "in stereo". Further tames the apparant volume to others on the street.
Including the local fuzz. My mufflers were custom built turbos but the off the shelf Dynomax Super Turbo mufflers achieve the same thing overall.
One of the reasons there is no drone is because the 2 exhaust pipes are different effective lengths. Your exhaust shop guy is on the ball.

Post a sound clip or video with sound.

[Dan Timberlake]

https://www.thecairns.com/Impala/IMG_5229.jpg

In the late 1960s several friends and foes removed the "resonators" from their 62-64 Impalas.
The new exhaust sound was much deeper, and louder.
I believe the resonators were the smaller mufflers shown in the above image.

Funny, I was recollecting they were mounted closer to the engine than the regular mufflers.