Measuring exhaust sound level (and quality)

[Joe250]

As some of you know from my previous posts, I have way too much time on my hands. When I was shopping for an exhaust recently I searched in vain for some really good sound clips/videos of the various aftermarket systems. I've since made my exhaust choice but before I install it, I intend to record a short video clip of the stock system and the Akra system with and without the baffles. I'll also be taking sound level readings at constant idle, 3k, and 4k rpm's, and then take a max level reading after a quick rev of the motor up to redline. By doing the testing with the same video camera, from the same distance, in the same surroundings (hopefully in a large open area), I should be able to get good relative comparisons.

The reason I'm writing is first to see if anyone in the SF Bay Area that has a Tuono (or RSVR) with another aftermarket system wants to participate - Leo Vinci, Akra Evo6, Arrow, Smalt, Tig, etc. Shouldn't take long and won't require much more than parking your bike for a while and running it while the video is shot and the sound readings are taken.

And finally, does anyone have any input on the best way to take the readings? Apparently racetracks here like Laguna Seca measure sound from the edge of the track approximately 50 feet from the bike. I plan to test that as well as from a distance of, say, 6 feet. If anyone has any thoughts or suggestions, I'm all ears.

[hope0001]

If you're thinking of obtaining noise level readings in dB, you need a calibrated noise meter.

Try hiring one (Goggle the words "Casella noise meter").

In theory you can download the noise graphs onto a laptop quite easily.


When I used to race 2-strokes, the scrutineers at the UK tracks would use a noise meter and a length of wood cut to 1 meter long so they always were the same distance away from the exhaust pipe end.

Try the same way, and then you'll be able to map dB at varying distances

Guy

[Joe250]

Although this won't be 'certified' calibrated, I do have one of these digital meters:



Its nothing fancy but again, I'm just trying to get relative measurements. It should give people a rough idea of how each exhaust sounds and how loud it is.

Joe

[Lardog]

Joe, I'm in so Cal so I'm of no use to you, besides, I have the Akras already but I will be interested in your db findings. I've had the plugs in and out and they are MUCH louder (especially at idle) with them out but of course I run with them sitting on a shelf in my garage

[splatty]

Sounds familiar Lardog, mine have no affect at all in the bubble wrap on the garage shelf.

Like you say, the idle sound can be disturbing.

I fired her up last Sunday, and thought "shit, she sounds noisy". Went for a 3 hour ride and even at idle in town centre traffic then she didn't sound too nosiy at all ??????????????

Must have been the ear plugs

[TuonoGrant]

Joe - I managed to get some vid clip of my cored cans. My fueling needs sorting however as its really rough. Not sure if its the TBds as I didnt get those checked after a quick switch to Map 2 at the dealers. Anyhow have a listen. Baffles are 2 inch inners and without its far to loud for me - to the point where it turns heads consistantly and is embarrising to ride down my block . No idea on the DB - but think no can loud. Cores are 65mm.

Click for Link File .wmv

[Joe250]

Nice Cuzzy! Thanks for posting that up. Your bike sounds excellent, especially at speed.

[Lardog]

Baffles are 2 inch inners and without its far to loud for me - to the point where it turns heads consistantly and is embarrising to ride down my block . No idea on the DB - but think no can loud.

I ride my bike to work 2 or 3 times a week (its only a 5.5 mile commute) and always find it funny that, when I pull into our parking garage, there are always two or three car alarms that get tripped when I ride by!